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6up2i3 | Cancer | I obviously know what it is and that it can kill. How though does it actually work and WHY if you have two people with the same lifestyle will one get it and not the other? | Repost | explainlikeimfive | {
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"Cancer is basically when some cells in your body get the wrong message. Normally, your cells grow and divide in a pretty predictable way, and then they die and are replaced by new ones more or less on schedule. Not cancer. These ones were told to GROW DAMN IT, so that's what they do. They just grow and grow and grow, even in ways they're not meant to or in places they wouldn't normally be. Cancer = abnormal, uncontrolled patterns of cell growth and division. This is basically what tumours are - they're made up of the cells that went batshit. As for *why*...truly, we don't have one clear answer yet. Some people have a genetic component, which is how you can have family histories of a particular cancer. For others, it's because of a lifestyle thing, a side effect of something they've done - lung cancer from smoking would be one, or one of the occupation related cancers like mesothelioma which turns up in builders or related tradesmen who've worked with asbestos. Sometimes it's a side effect of a much more minor medical issue, like how cervical cancer is connected to genital herpes. Some people are just plain unlucky. The reason *why* doesn't really matter. If you've got cells in your body that have started dividing and growing uncontrollably, that's cancer."
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6usu3r | Where do photons go after you turn off a light that was in the middle of a closed dark box with mirrors on all sides? | Repost | explainlikeimfive | {
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"All mirrors in the world are imperfect, that means a small amount of the energy a photon holds is converted into heat when striking a mirror's surface. Light moves very quickly so it quickly converts essentially all the light energy to heat one bit at a time. Eventually the kinetic energy in the photons drops low enough that we don't perceive light from them anymore."
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6ut9vj | Why does the hot water out of the tap look cloudy? | Repost | explainlikeimfive | {
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"Yarr! Yer not alone in askin', and kind strangers have explained: 1. [ELI5: Why does hot water out of the tap look cloudy. ]( URL_7 ) 1. [ELI5: Why is hot water from the tap always cloudy? ]( URL_0 ) 1. [ELI5: Why does hot water come out white/cloudy from the tap but when I boil cold water it is transparent? ]( URL_2 ) 1. [ELI5: Why does hot water come out of the tap white, but cold comes out clear? ]( URL_5 ) 1. [Why does tap water turn cloudy when it gets hot? ]( URL_6 ) 1. [ELI5: Why does hot water look cloudy sometimes? Why would hot water from a faucet be cloudy, even tho it's crystal clear when cold? ]( URL_3 ) 1. [ELI5: Why hot water out of the faucet sometimes appears cloudy or white in color? ]( URL_1 ) 1. [ELI5:Why is wam tap water not see through? ]( URL_4 ) 1. [ELI5: Why is hot water white right when it comes out the tap? ]( URL_8 )"
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6uvmqg | Bacteria become resistant to antibacterial products but why not bleach and alcohol? | I understand that some of the bacteria survive the antibacterial products and the ones that survive are more resistant, however why doesn't some bacteria survive alcohol or bleach and become more resistant to those products? For example, if I swap my skin with alcohol even if the bacteria under the swab are all killed when there be some on the edge that would survive but get a partial dose of alcohol? | Repost | explainlikeimfive | {
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"Imagine a bacterium as a big factory, with the bacterium's membranes and cell wall being like the factory's walls and ceiling, the enzymes like the factory's machines and the DNA like a big book of instructions for building the factory. An antibiotic is like sending a saboteur into that factory - maybe to break a critical piece of machinery, or to blow up a structurally important support pillar. The factory could counteract that sabotage by, say, positioning guards that could catch the saboteur (similar to how bacteria may become immune to an antibiotic by mutating an enzyme that can break down the antibiotic. Bleach or alcohol (or also heat) are more like carpet-bombing the factory until just a pile of rubble remains - they damage a bacterium in many different places at once, and in a much cruder manner. That is also why you cannot use them internally to fight an infection - they would cause too much collateral damage to your body's cells.",
"It's the mechanism. Antibacterials work internally to disrupt processes and alcohol is external. It's like how you can tolerate my alcohol with repeated exposure but you can't tolerate more fire no matter how much you try",
"There is another aspect to resistance that most replies have neglected. Bacteria can and do become resistant to alcohol/bleach/heat/whatever if given enough time. There is a species of bacteria colonising wine vats that can withstand up to 90% ethanol for prolonged time, for example. The problem with most bacteria in a typical setting is that the cost of developing such resistance far outweigh the benefit of having them. Penicillin resistance is taxing enough for bacteria that they lose the natural selection race if there is no such antibiotics around. Alcohol content of over 10% is an extremely rare environment, so any bacteria that develop such resistance will be quickly selected out as well.",
"Antibacterials target certain parts of the bacteria. If a single bacterium is born without that part, it will be resistant. Alcohol and bleach, however, just kinda go in and fuck everything up, which is kinda impossible to avoid.",
"Picture a working computer. You need to make it stop working. One thing you could do is to pull the plug. It will work, but there are ways around it, like installing an internal power source. Alternatively, you could drop a nuke on it. There's not much that can be done to prevent it. Antibiotics work like pulling the plug, and bacteria can develop adaptations that protect against it. Alcohol and bleach work like nukes. We have to use antibiotics when we can't just drop a nuke - like when the bacteria is inside your body, and drinking bleach, while certainly effective, will also destroy the rest of the body. But your skin is tough enough to take it.",
"I know this isn't ELI5, but these are the underlying mechanisms. Bacteria are little guys with cell walls to protect them from the world. When we put something in say a dish to kill said bacteria, they react in different ways in order to protect themselves. When a bunch of a substance (Penicillin or something of the sorts) comes to the bacteria, it has four choices: refuse, spit it out, tolerate, neutralize. This sounds similar to humans with foods, but back to bacteria. The bacterium (only one) crawls over to your antibiotic in question and several things can happen. If the bacteria doesn't recognize it (through a protein on its wall), then it may be absorbed as possible food/pass through the cell wall. If the bacteria has learned that this antibiotic can hurt it and has a protein to identify it before it gets in, the bacteria will ignore the substance. If the bacteria absorbs the substance, then proteins inside can identify it as a hazard and then spit it out (some bacteria even specialize in very efficiently eliminating substances that enter). The bacteria can also recognize the substance, and make a protein to break up the substance so it is no longer a threat. Finally, the bacteria can just learn to tolerate the substance through continued exposure (through a mixture of the previous three methods). So how come bleach/alcohol ALWAYS seem to work? They're such small substances that you can't stop it from getting in, that it can't be broken down further, or if it is broken down then it will become more toxic than the precursor. Other redditors have ELI5'ed this, but a full answer may help some understand it a little better."
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6uw1ar | Why do we get butterflies in our stomach? | Repost | explainlikeimfive | {
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"When you get anxious, your muscles (including stomach muscles) tense and become hyper-sensitive as part of the body's fight or flight response. You feel it in your stomach more because there of the vast amount of neurons linking the stomach to brain."
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6uzpy2 | Why isn’t there an autocorrect type thing for coding? Wouldn’t that make things significantly easier than having to go through and manually find an error? | Repost | explainlikeimfive | {
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"There are auto correctors for code. But just like with text they correct some orthographic rules and maybe some grammar, they cannot correct if what you code will do what you want, the same way an autocorrector can fix a typo but not the idea you want to communicate.",
"What tools are you using? Intellisense (autosuggest) and syntax checking/highlighting is common in most modern development environments. Some will even spell check your string literals.",
"There are plenty of tools that are typically called \"intelisense\" (named from the tool in Visual Studio) included with your IDE of choice. These \"auto-complete\" tools lookup possible program objects while you type, and provide suggestions (eg. `spri` - > suggests `sprintf`). They'll also typically underline any piece of text that looks like it *should* be a specific type of object, but the definition doesn't exist (eg. a function call to a function that was never defined). However there are plenty of things that the auto-correct could never understand how to fix. Tools will spit out errors like `missing '}'` with no way to fix it, because there's probably hundreds of valid places you could have meant to put the closing brace. You're telling the compiler `if (something happens) { thing1(); thing2(); thing3();` and it has *no* idea if `something` was supposed to predicate all 3 actions, 2 actions, or just the first one. So it can't do any better than explain `i didn't find the closing }`. Things get even more confusing when it sees `if (something1) { if (something2) { thing1(); thing2(); }` because it again knows only that a missing brace happened, but it doesn't know if the one it does see was supposed to pair off with the first or second if statement."
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6v181b | Why do we/can we feel the physical pain of a heartbreak or loneliness in our chest? Why do we feel physical pain at all if it is a process that is mostly in our heads? | Repost | explainlikeimfive | {
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"Yer not alone in askin', and kind strangers have explained: 1. [ELI5: Why does my chest hurt when I experience heartbreak? ]( URL_5 ) 1. [ELI5: Why is it that when you experience heartbreak there is an actual physical pain in your chest? ]( URL_6 ) 1. [ELI5: Why do we feel heartbreak ? ]( URL_4 ) 1. [ELI5: why do you feel heartbreak and grief so physically? ]( URL_0 ) 1. [Why does my heart actually feel \"heartbroken\" or hurt when im only emotionally affected? ]( URL_2 ) 1. [ELI5 When you are \"heartbroken\" what is really going on chemically in your body? ]( URL_1 ) 1. [ELI5 how does getting your ' heart broken ' happen? Isn't love just an emotion that has nothing to do with an organ that pumps blood? ]( URL_3 )",
"I would love to know this too. I remember when I lost my mom, it felt like if I looked down at my chest, I'd see a gaping hole. It felt as if my centre had been ripped out of me. Grief is so powerful, it can feel physical. I wish I could answer your question, but I'm definitely curious about the answer."
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6v1v1d | Digestion takes about six to eight hours through your stomach and small intestine. Food then enters your large intestine for further digestion. What happens when you eat something bad, and all this is reduced to minutes? | Repost | explainlikeimfive | {
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"So your bowels are like a long train track and your food is like a set of cars on the track. Transit time between Point A, your mouth, and Point B, the chute, is a bit flexible but normally operates on a regularly scheduled basis. When you eat, you put cars on the track and send them to Point B. As these cars go to Point B, they lose passengers (nutrients) at various points in the thin tunnel portion (small intestine). The journey isnt complete and the journey has already altered the shape of the car pretty significantly giving a rusty color. Once in the larger portion of the tunnel, the cars are checked for stray passengers and are hosed down a bit so that transition out of Point B isn't so bad. Sometimes, the train cars park juuust outside the gates of Point B so they can exit at the best time for the operator (toilet). Now, all of this goes fucking nuts when you load a bad set of train cars at Point A. The track sensors located everywhere along the track, detect this alien set of cars and sends a distress call to the Supervisor (your brain). The Supervisor wants to handle the situation without having to phone the Manager (your consciousness) about the craziness on the tracks and also wants to make sure you never know it was on the tracks. It has to make a choice now: send it back to Point A violently and somewhat painfully risking tearing the tracks, or send it to Point B as fast as fuck? Depending on where it's located on the track, it'll choose the best route. Let's use the destination Point B. The Supervisor hits the panic button and puts all the train cars that are on the track (in your body) on overdrive. The tunnels are flooded with water and lubricant to speed all the cars up and get them the hell out of there as quickly as possible. Cars collide with each other, and previously well formed cars are just flooded with water and lubricant that they are just a soggy, shadowy reminder of their former glory state. The Media (pain) hears about the car collisions immediately begins filming live the high speed, flooded train cars out of control. They want to knos how an alien set of train cars were put on the tracks and they want someone to pay for such carelessness. The Manager is just watching the horror unfold on Live TV but cannot do anything to stop it, because the Supervisor was deaf and he had not installed a means of communicating with him after hours in the office. I hope this answers your question. TL;DR when you get diarrhea, everything gets pushed out, one way or another. There are no passing lanes. Source: /u/jiggity_gee",
"Bad food enters. Stomach is all like \"Red Alert! Battlestations\" and quickly determines \"Abandon ship! Everyone to the escape pods\" and some faux scottish guy is like \"All the escape pods are jammed\" so hammy captain is like \"Can we flood all the escape pods with some extra fluid to lubricate the escape pods\" and the engineer guy is like \"sure but it will be messy\" and then a euridite snob is like \"make it so\" and bam! All the escape pods leave in a hurry.",
"This has come up before. I searched for 'digestion' and found these. URL_1 URL_0 Thanks for the down votes people but I wasn't shooting OP down. I was trying to link to more answers.",
"Body detects something bad. Wants to get rid of it. A lot of water is spent to get the whole batch going, bowel movement intensifies. Ta da! You are now basically a water-propelled rocket with far to low, yet still impressive thrust.",
"What everyone else said, but I wanted to point out that if you have diarrhea literally minutes after eating, is is probably not caused by what you just ate. What you just ate is almost all still in your stomach. 2.5 hours after eating, half the food is still in your stomach. For this reason, symptoms of food poisoning don't usually set in until 6-9 hours after eating something bad. People often think they had a bad meal at a restaurant, when it's really the breakfast or lunch they cooked themselves. Edit: To clarify, yes, I'm mostly talking about food poisoning here. There are other things--lactose intolerance, IBS, etc., that might cause your digestive system to freak out immediately upon eating. Even in those instances, though, the food you just ate is still mostly in your stomach. What is happening in those instances is that your large intestine is being flooded with water. When we are talking about diarrhea, we are mostly talking about things happening in the large intestine. The stuff in the stomach and small intestine remain chugging along at their usual pace (usually).",
"Where did you hear about these 6 to 8 hours? BBC did a study with ingestiable sensors and it took about a day and a few hours for a meal to pass from one end to the other.",
"The short answer is this: when your body believes it's been poisoned, everything is suddenly on the express line out to get rid of that poison before it's metabolized. You can't really slow down digestion and just hold onto that stuff, so you have to get it out.",
"This happens due to the body reacting to foreign or dangerous substance and decreasing water resorption through chlorine pumps to allow it to move through much faster. The body will not wtrempt to absorb nutrients from bad food. When you get diarrhea from a bacteria or amoeba they often damage the cGMP or cAmP receptors leading to chlorine leakage or retention leading to water retention or excretion. This is how both diarrhea and constipation work",
"It slows down at the end in your large intestine and/or colon where you reclaim fluid and certain nutrients. Think of it like a cork. Once that goes, things move along much quicker. Gas, does in fact cause pressure. The gas usually just creeps around a turd and your sphincter is like \"sweet, break time.\" With the runs, you get a downward facing champagne bottle. It can't discriminate between air and fluid like it can with air and solid, so you shart.",
"FYI, most of the time when you get sick from having eaten something, it's something you ate 12-18 hours ago, depending on how long your digestion takes. Occasionally if you eat something really nasty, your stomach will revel far quicker when the food gets to your stomach. But often you're reacting to something you ate a while ago.",
"Your stomach is line a tunnel. Food passing through are cars. Normally with food, these cars pass through the tunnel slowly, steadily, taking their time to pass through the tunnel and be absorbed, broken down etc. During spicy food or food poisoning, this tunnel is flowed and they try to move all of the cars through the tunnel and out asap to minimise damage (aka you shitting it out)"
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6v8pdu | In films and TV, how can they make those shots in which the character looks at themselves in the mirror but have the camera not show up in the mirror too? | In many scenes the camera points at the mirror and the character is moving and we can see both the person and their reflection but not the camera's reflection... how? | Repost | explainlikeimfive | {
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"Put something in front of the mirror and pretend it's your actor. Now move off to the side. You can see the object and the reflection without being in view yourself. It's just a matter of positioning the camera the right way. They just change the angle of the camera and actor. The actor doesn't actually even need to see his reflection as long as you can. There are other tricks, too. You can disguise the camera, edit it out, or build a set with two identical, reversed rooms and have a look-alike fill in for the actor from behind."
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6vam0p | Why do many cultures all around the world have Dragons even if they never heard about them from each other? | Repost | explainlikeimfive | {
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"When things like this happen, it's usually either because the idea appeared very early when there was a small number of people or that it arose because of some common experience across the globe. In the former, those people go on to tell the same stories to the generations that follow them, even as populations spread across the planet. As a result, the story becomes widespread. This is one hypothesis to explain why many cultures have stories similar to the story of Jesus: early societies came up with the story, which was then propagated generationally and ultimately spread over a large geographical area as these generations expanded into new areas. In the latter, something is a universal experience, and we may perceive it as a pattern of particular significance. For example, pyramid shaped structures are very stable and convenient when your building technology limits you to stacking things. As a result, many cultures independently discovered pyramids, and they are fairly widespread structures across the globe. Another example here is the great flood, which may have been due to sea level rise as global climate changed early on, before we had a scientific explanation for it. As a result, many cultures speak of a great flood.",
"Because dinosaur bones are found pretty much everywhere so it's easy to imagine them being found and myths created to explain them. Voilà, dragons.",
"Do you believe that humans NEVER in all of history before modern times stumbled across dinosaur bones? The legends of dragons most likely stem from early fossil finds coupled with some tall tales from those who possessed specimens.",
"Most cultures around the world have been in contact with each other for at least 5000 years. So it is not unthinkable that most dragon myths have the same origin. However the different cultures describe the dragon in lots of different ways so it is possible that there are lots of different creatures in mythology that we today call dragons even if they have different origins. For your statement to be true you need to find two dragon myths that is similar enough to be called the same creature where the two cultures have been separated from the rest of the world for several thousand years. The only such culture groups are the American cultures which in large parts separated from the rest of Europa, Asia and Africa and developed independently. Granted that Vikings likely had contact with the native Americans and Viking ships often had carvings of creatures resembling dragons on them. But even then we do not find many creatures in American culture that resembles the classical dragon. There is creatures that have been described as dragons but apart from being composed of parts from different animals and having scaled skin it does not have many of the traits that is common in dragon myths in European and Asian cultures."
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6vayyl | how did people count years before they startet using the birth of Jesus christ as a time frame reference? | Repost | explainlikeimfive | {
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"Common methods of reference would be how many years into the reign of the current ruler, or years past some significant event known to their intended audience.",
"There really wasn't a standardized system for this before Jesus (or even for a good 800 years after his death); Some ones from the Roman empire include: * The names of the two consuls who held office that year (\"in the consular year of XXX and YYY\") * The time since a Caesar took the throne (\"in the sixth year of the reign of Julius\") * The calendrical epoch of the Olympiad, or counting the time since the last Olympics (\"in the third year of the Eighth Olympiad\") The most interesting one, IMO, that is still used in some form, is the Jewish system that Christian scholars called \"Anno Mundi\" or \"the year of the world\" (according to Judeo-Christian creation myth), which is currently clocked at 5771. Source: URL_0"
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6vc1bo | If we know that Absolute Zero is the coldest temperature possible, why is the hottest temperature possible not known? | Repost | explainlikeimfive | {
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"There are a lot of wrong answers here, claiming that all molecular motion stops at 0K. *That is not true at all!* Heisenberg's uncertainty principle tells us, that it is impossible for atoms and molecules to have zero kinetic energy. Every bound system has [zero point energy]( URL_0 ). So, what does absolute zero really mean? --- Quantum mechanics tells us that bound particles cannot have an arbitrary amount of energy. Instead, they can only hop between energy levels. And the lowest of these energy levels is still not 0J. *The lowest energy level still has kinetic energy - the so called zero point energy.* Thus, a bound particle must always have motion energy. What absolute zero really means, is that all particles are in this lowest energy state, which is called ground state. Since there is no way a system can have less energy than all its particles being in the ground state, there can be no colder temperature than absolute zero. In fact, due to the uncertainty principle, even reaching 0K is fundamentally impossible. What about a hottest temperature? --- There is no theoretical hard upper limit on temperature. There wouldn't be any mechanism preventing you from adding more and more energy into a system. In some way, of course the total amount of energy in the universe is an upper limit, but that really isn't very descriptive. Some people claim that the upper limit is posed by particles moving at the speed of light. That is *not true*. Even though the speed at which particles can move is limited, their *kinetic energy* has no upper bound. As temperature scales with energy, not speed, the speed of light does not pose an upper limit to temperature.",
"Temperature has to do with how quickly the particles are moving. So the slowest is zero movement, right? But that gives us no indication of what the top speed is."
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6vcbxd | Is it a crazy coincidence that the moon perfectly blocks out the sun? | Repost | explainlikeimfive | {
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"Yes, it's just luck. The Moon is slowly moving away and the Sun is slowly growing. In a million years it won't be big enough for total eclipses anymore.",
"Yes. The moon just happens to be at the right distance from the earth such that its size blocks out the almost completely (almost all the time). There are times when it is a bit further than optimal and you get an annular solar eclipse."
],
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|
6vdpx7 | How can animals eat their prey without cooking it and be fine, yet if humans do we would get extremely sick/diseased? | Repost | explainlikeimfive | {
"a_id": [
"dlzfn1n",
"dlzfymw"
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"text": [
"Animals don't save their meat to be eaten later. You could eat a freshly-killed deer or something raw as well, provided it doesn't have parasites. But when you bring it home to eat later, bacteria start growing on it. You have to cook it to make it safe again.",
"We eat raw meat all the time (Sushi, steak tartare). It has to be fresh, with no diseases or bacterial growth. Animals are exactly the same. The ones that eat roadkill and other already-dead animals are resistant to the microbes on the old dead meat."
],
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6vdx60 | Why do giant characters in movies and tv shows seem to move in slow motion rather than at normal speed? | Repost | explainlikeimfive | {
"a_id": [
"dlzi9ns"
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"text": [
"Something that is far away from you looks like it's moving slowly, even when it isn't. Think of watching a plane move across they sky; it's going 500mph, but seems to crawl across your view. A giant who's far enough away to fit on the screen will be moving fast, by virtue of being huge, but will still seem to move more slowly because they're further away. Also, it's just a visual trick/cue used to add perceived mass and size to something when you aren't actually there to see it in 3D with proper perspective to the things around it."
],
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|
6vf42k | How do they construct underwater tunnels? | Repost | explainlikeimfive | {
"a_id": [
"dlzrnek"
],
"text": [
"According to google \"To use this method, builders dig a trench in the riverbed or ocean floor. They then sink pre-made steel or concrete tubes in the trench. After the tubes are covered with a thick layer of rock, workers connect the sections of tubes and pump out any remaining water.\""
],
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|
6vf75w | Why do we consider gold valuable? | Repost | explainlikeimfive | {
"a_id": [
"dlzry3l",
"dlzw7ld"
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"text": [
"Gold is one of the most maleable, attractive and useful metals in the world. In antiquity it was praised for its luster, its shine and its beauty. It was molded into jewelry, used for decoration and used as a luxury item. In ancient times, it was used as currency, stamped with faces and shown to the world and born as a sign of wealth in a nation. Gold was the currency that made the world turn and was internationally turned to as the \"gold standard\" for international trade along with local currencies like Rice bundles, Wheat bundles and animal trades. In modern times, Gold is used in many applications that range from textiles to electronics. Being both maleable and able to withstand massive abuse without destruction, Gold makes a wonderful plating element and beautifying agent for art, decor and embellishments. As a product in science it conducts heat and electricity, and can be made very, very small in size to inhabit spaces no larger than the width of a hair as a conductor or plate items to be a heating element. Gold is more prolific than many other elements also because of its lack of reactable components. Gold is very hard to dissolve and doesn't bond easily to other things, where Iron or copper bond freely with hydrogen and oxygen to form compounds and ions that tarnish the surface and ruin it's uses.",
"Yer not alone in askin', and kind strangers have explained: 1. [ELI5: why is gold so much more valuable than silver? ]( URL_4 ) 1. [ELI5: Why is gold so valuable? And why is it more valuable than other metals, like silver? ]( URL_0 ) 1. [ELI5: Why is gold valuable? Also, why was gold important to ancient civilizations? ]( URL_3 ) 1. [ELI5: Why is gold valuable? Especially during the Gold Rush. Can it be used for something? ]( URL_7 ) 1. [ELI5 Why is gold and jewels considered so valuable? ]( URL_2 ) 1. [[ELI5] Why is gold so valuable? ]( URL_8 ) 1. [ELI5: Why is gold so valuable to the world? ]( URL_9 ) 1. [ELI5: How did gold go on to become so valuable? ]( URL_6 ) 1. [ELI5: Why is gold worth so much money in modern times? ]( URL_5 ) 1. [ELI5: Why is gold so valuable? ]( URL_1 )"
],
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"https://www.reddit.com/r/explainlikeimfive/comments/1utlb8/eli5_why_is_gold_so_valuable_and_why_is_it_more/",
"https://www.reddit.com/r/explainlikeimfive/comments/535k5x/eli5_why_is_gold_so_valuable/",
"https://www.reddit.com/r/explainlikeimfive/comments/3uds0b/eli5_why_is_gold_and_jewels_considered_so_valuable/",
"https://www.reddit.com/r/explainlikeimfive/comments/6hqho6/eli5_why_is_gold_valuable_also_why_was_gold/",
"https://www.reddit.com/r/explainlikeimfive/comments/5mnx11/eli5_why_is_gold_so_much_more_valuable_than_silver/",
"https://www.reddit.com/r/explainlikeimfive/comments/1mhujj/eli5_why_is_gold_worth_so_much_money_in_modern/",
"https://www.reddit.com/r/explainlikeimfive/comments/42q0ir/eli5_how_did_gold_go_on_to_become_so_valuable/",
"https://www.reddit.com/r/explainlikeimfive/comments/3i1paa/eli5_why_is_gold_valuable_especially_during_the/",
"https://www.reddit.com/r/explainlikeimfive/comments/3qcvxj/eli5_why_is_gold_so_valuable/",
"https://www.reddit.com/r/explainlikeimfive/comments/2s2k4d/eli5_why_is_gold_so_valuable_to_the_world/"
]
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|
6vg6si | Does getting 8 hours of sleep broken up throughout the day give you the same physical rest as sleeping 8 hours straight? | Repost | explainlikeimfive | {
"a_id": [
"dm00wuz",
"dm0dle7",
"dm0be4e"
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"text": [
"The short answer is yes - There are a few different \"alternative\" sleep cycles out there. One is the Uberman cycle, where instead of taking a long 8 hour nap, you take 20 minute naps every 4 hours for a total of 2 hours per 24 hours. The idea is to get your body trained to reach REM sleep quickly, as that is when your body rests and repairs itself. In a standard sleep schedule, it may take your body a few hours to reach REM. There haven't been really any side effects reported, although data is limited. I did this for about 6 months and I felt great and well rested. The amount of time I had everyday was incredible. The only thing is that school and work tend to fit around a normal sleep schedule, so it makes it difficult.",
"This guy tried polyphasic sleep for an extended time: URL_0",
"While it's the most famous polyphasic sleep style, the Überman was suggested by a woman in a forum who claimed to have done that during her university times. For really looking into it you should start with something easier like the Everyman or a simple biphasic schedule."
],
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|
6vga1c | How do some companies like Hooters get away with only hiring a certain demographic, in this case women, for employment when companies are supposed to be equal opportunity? | Repost | explainlikeimfive | {
"a_id": [
"dm01i29"
],
"text": [
"BFOQ: Bona Fide Occupational Qualification. To be a \"Hooters Girl,\" one must first be a girl. They hire males to bartend, bus tables, cook, clean and manage, if any are to apply and be qualified."
],
"score": [
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|
6vipz2 | Why do we have dominant hands (feet, eyes etc...)? | Repost | explainlikeimfive | {
"a_id": [
"dm0puiq",
"dm0izpo",
"dm0tybi",
"dm0yw91"
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"text": [
"Imagine something flying towards your head. It's quicker to not have to decide which hand you put up to block your head. Instead you usually put up your dominant hand.",
"To save brain space. Having both limbs be dominant doesn't offer enough of a benefit to justify the increased use of resources in the brain.",
"IANAS but based on what I've seen it's a sort of random roll of the dice of your brain. Your brain essentially chooses a hand based on need when you're learning very basic motions and actions as an infant, those skills grow, muscle memory sets in. This accounts for the random variation of mixed tasks, not quite being ambidextrous, but some actions are done with the right hand and some with the left, enough to question the actual \"dominance.\" For example I am one of two members of my family (immediate and extended) who writes with their left hand. However, I play all sports as right handed person would EXCEPT for throwing (I throw left handed). This is all anecdotal but given the number of anecdotes I can personally think of, I would put money on it being a developmental roll of the dice.",
"I believe this question was asked here sometime before. Let me try finding it. There were some great answers there. Edit - Here it is URL_0"
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6vjoja | How can a Food have 0 Calories? | Repost | explainlikeimfive | {
"a_id": [
"dm0p532",
"dm0tc5u"
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"text": [
"1. The amount of calories food is the amount of energy your body can extract from it. Some food doesn't contain any usable energy, for example water or salt (the body still needs them, but not for energy). 2. In the US, food companies are allowed to mark certain items as having 0 calories if they have less then a certain amount per serving. For example Tic-Tacs have less than 0.5 grams of sugar per serving (which is one mint), so they can say they have 0 calories.",
"Yarr! Yer not alone in askin', and kind strangers have explained: 1. [ELI5: How Can Something Be 0 Calories? ]( URL_2 ) 1. [ELI5: How can a drink have 0 Calories? Does that mean it gives no energy when you drink it? ]( URL_5 ) 1. [[ELI5] - How is it possible to make \"zero calorie\" food? ]( URL_0 ) 1. [ELI5: How can some drinks/foods be labeled as 0 calories? ]( URL_6 ) 1. [ELI5: Why do things with 0 calories have a \"serving size\"? ]( URL_1 ) 1. [ELI5: How can pickles have 0 calories per serving? ]( URL_3 ) 1. [ELI5: How can a food product contain zero calories? ]( URL_7 ) 1. [ELI5: How Does Diet Soda Have 0 Calories? ]( URL_4 )"
],
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[],
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"https://www.reddit.com/r/explainlikeimfive/comments/j4xs0/eli5_how_is_it_possible_to_make_zero_calorie_food/",
"https://www.reddit.com/r/explainlikeimfive/comments/2giudu/eli5_why_do_things_with_0_calories_have_a_serving/",
"https://www.reddit.com/r/explainlikeimfive/comments/6h281d/eli5_how_can_something_be_0_calories/",
"https://www.reddit.com/r/explainlikeimfive/comments/4mij54/eli5_how_can_pickles_have_0_calories_per_serving/",
"https://www.reddit.com/r/explainlikeimfive/comments/3pdt47/eli5_how_does_diet_soda_have_0_calories/",
"https://www.reddit.com/r/explainlikeimfive/comments/359ufx/eli5_how_can_a_drink_have_0_calories_does_that/",
"https://www.reddit.com/r/explainlikeimfive/comments/37ghac/eli5_how_can_some_drinksfoods_be_labeled_as_0/",
"https://www.reddit.com/r/explainlikeimfive/comments/267z7j/eli5_how_can_a_food_product_contain_zero_calories/"
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|
6vju2g | Why do strong smells linger in a room even after the source of the smell is gone? | Repost | explainlikeimfive | {
"a_id": [
"dm0qn31"
],
"text": [
"Your sense of smell is nothing more than specialized nerve cells in your nose reacting to particles of matter in the air. When you smell a flower, for example, you are breathing in pollen from that flower which stimulates your nasal cells and registers as the smell of a flower. Smell lingers in a room because there are still particles in the air from the source lingering around in the air for your nose to register."
],
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|
6vlvp8 | How do sites, like Youtube, get ads to load instantaneously but I have to wait for the video to buffer? | Repost | explainlikeimfive | {
"a_id": [
"dm1ajp4",
"dm17waz"
],
"text": [
"To blow your mind more: not only is that ad loading \"instantly\", but in the milliseconds before you see it, your personal tracked information is being uploaded/read in an online ad market, and thousands of ad placement bots are bidding on the right to show you their ad. That space may get hundreds of bids before the winner is selected and that particular ad shown. It's even more complicated than all that, but I paraphrased.",
"Ad video data is placed at higher priority than content videos. Both in streaming pipeline as well as storage access."
],
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|
6vpchr | Why do we tend to walk when talking on the phone? | Repost | explainlikeimfive | {
"a_id": [
"dm1zeux"
],
"text": [
"\"When we go for a walk, the heart pumps faster, circulating more blood and oxygen not just to the muscles but to all the organs—including the brain\". So it seems walking makes you smarter when answering that job interview call, or when your girlfriend asks where you are right now. ( URL_0 )"
],
"score": [
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],
"text_urls": [
[
"http://www.newyorker.com/tech/elements/walking-helps-us-think"
]
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|
6vq7mk | How did the first of ancient travellers communicate with people from a different part of the world, without knowing their language? | Repost | explainlikeimfive | {
"a_id": [
"dm243iu",
"dm2414b"
],
"text": [
"Like we do today, with gestures, pointing, and drawing. If I'm dropped in a foreign country and need to communicate, the first thing is to see if they can speak or understand my language, however unlikely. Next is pictures, they really are worth 1000 words, if I draw a picture of a steak and gesture to my mouth like I'm eating then 99% of the time the fact that I'm hungry will be communicated. The other 1% I have just insulted his mother and he takes my head off, but still communication with out knowing the language.",
"> without knowing anything it's almost impossible to learn a new language. Not at all. After all, every single person on Earth has learned at least one language without knowing anything. It's how children lean their native language(s). As an adult, I point to a tree and say \"tree\". You point to the tree and say \"arbre\". Now we each know what the word for tree is in our respective languages. Repeat that for common objects, and by miming actions, and you get a good base of nouns and verbs. Throw in some adjectives (you point to several red things and say \"rouge\", and now I know your word for red), and you've got enough of the language to be able to communicate."
],
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|
6vqle6 | how can time go faster on a different planet? | Repost | explainlikeimfive | {
"a_id": [
"dm268wi"
],
"text": [
"Because time and space can be twisted by huge masses (or high speed can change how they effect us). The gravity and blackholes are the proof ( also there are theories of scientists such as Einstein). If you wonder the gravity is not like how oppsite sides attract each other. The gravity is the space we are in itself being pulled by a huge mass."
],
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|
6vr8tf | Why do some Countries use 240v and some use 120v for appliances? | Repost | explainlikeimfive | {
"a_id": [
"dm2bfvi"
],
"text": [
"All countries use high voltage for transmission but different levels of transformer to lower the voltage. Its more expensive to step down to 110 or 120v so 3rd world use 220v or 240v for non industrial use"
],
"score": [
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|
6vta2q | What happens when you 'pull a muscle'? | And what is a muscle 'knot'? | Repost | explainlikeimfive | {
"a_id": [
"dm33v1g",
"dm2xfmq"
],
"text": [
"Ahoy, matey! Yer not alone in askin', and kind strangers have explained: 1. [ELI5:What actually happens when you \"pull\" a muscle? ]( URL_0 ) 1. [ELI5 What is the difference in a muscle strain/pull and normal fatigue from working out. Why does one heal so much faster. ]( URL_1 ) 1. [ELI5: say you pull a neck muscle and now it hurts to turn your neck after a certain extent that causes you to stop turning. is this because your neck physically cant turn anymore and youre trying fighting it, or does the pain alert the body to stop before more harm? ]( URL_2 )",
"And how to resolve it? I pulled my back muscle front squatting 30mins ago."
],
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"https://www.reddit.com/r/explainlikeimfive/comments/1nmj8s/eli5what_actually_happens_when_you_pull_a_muscle/",
"https://www.reddit.com/r/explainlikeimfive/comments/5nv2eb/eli5_what_is_the_difference_in_a_muscle/",
"https://www.reddit.com/r/explainlikeimfive/comments/59vym5/eli5_say_you_pull_a_neck_muscle_and_now_it_hurts/"
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6vwyb9 | Why is someone recording themselves talking about a murder they committed a confession, but at the same time rappers and others in the music culture talk about murder and drug use constantly in their music with no negative repercussions at all | Repost | explainlikeimfive | {
"a_id": [
"dm3makp",
"dm3mg73",
"dm3m8nl",
"dm3mlro"
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"text": [
"Bobby Shmurda actually gave info towards crime and gang related activity police were looking into in his music and it was used to help build a case lol. So it’s not necessarily without any consequences, especially if what you say can incriminate you of a particular open case",
"There are two factors at play: 1. specificity. That is, does the confession/song describe a specific illegal act within the scope of the jurisdiction and statute of limitations. For example, if Johnny Cash says he \"shot a man in reno just to watch him die,\" which man? When? If Johnny Cash instead sang, \"While traveling in Reno on or around January 4th, 1985, I shot a man named Jim Fuller, who was wearing a red shirt at the time, with a .32 pistol then dumped his body in the river, just to *watch* him die\" and the police confirm that a man named Jim Fuller was found dead in a river in Reno due to a gun shot would on January 6th 1985, that would certainly be admissible evidence. Likewise, if a confession was too general, (\"I killed a lot of people then ate them\" \"what people?\" \"Just people, random people\" \"when?\" \" you know, over time\" \"where?\" \"all around\") there's no **specific** crime to tie it to. 2. actually happened and is possible. If Johnny Cash confess to, or sings about, killing Jim Fuller (as above) but there's no evidence that a Jim Fuller died in Reno on or about January 4th 1985 due to a gun shot wound, or Johnny Cash was in LA at the time, it's a moot point. Likewise, if I confessed to assassinating Kennedy, it doesn't much matter as I was not alive at the time.",
"There is a significant difference between the freedom to express oneself through the art medium of music, and actually confessing to commiting a crime. 'I shot the sheriff' is a wonderful example.",
"A person recording themselves talking about a murder they committed is not a confession unless they're making a sworn statement. It does, however, give a reasonable excuse for police to investigate them, maybe even make an arrest while they search for evidence. Artistic expression (and freedom of speech) allows people the right to say just about anything they want. If they're just making vague statements (I shot a man in Reno just to watch him die), the police have nothing to go off of. In my example, all they have is that someone got shot in Reno. Without a name, a body, a murder weapon, a time, a date, they don't really have anything to go off of."
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6vxz1k | What is the "resolution" of the human eye? It is possible to create a camera with a resolution higher than the human eye? If so, how would we perceive the photos it takes? | Repost | explainlikeimfive | {
"a_id": [
"dm3ub40",
"dm3u9q7",
"dm3ur48"
],
"text": [
"I think first we have to define what we mean be \"resolution\". The reason being that the retina of the eye is not the same across all of it: we have a fovea - a small area of tightly packed light-sensitive cells in the centre of the retina. When we look at something, this is where the image is sharpest for us (This part is about 16Mp), with the image sharpness quickly falling off toward the edges of the retina. However, we can move our eyes to \"scan\" a scene (with our head being still). If you were to calculate the total Mp of this \"scanned\" scene using the fovea as your base, it would apparently add up to something like 576Mp! Although this sounds unbelievably high-resolution, there are cameras that can top this. They are called \"scanning cameras\" and essentially they are a high-res scanner with a lens mounted in above the plattern, much like the old \"bellows cameras\" of yesteryear, but with a scanner in place of a glass plate. These can scan images of over 1Gp! VSauce has a great video which breaks it down and explains it much better than me! URL_0",
"Why are empty threads showing up on the front page? This makes no sense.",
"The resolution of the human eye depends on how far away an object is. You will notice more detail from a 1080p screen (1920x1080 pixels) on a smart phone placed 10 inches from your face, than from a 1080p TV located far away from the couch you are sitting on. The human eye has some major differences from a camera. The light sensing part of our eye, the retina, has a very high concentration of colored-light sensing cells (this is similar to single pixels in a camera sensor) in the very center of our vision which falls off quite rapidly. This high resolution in our visual centers is why it is easy to notice detail in the center of our vision but not off-center. In contrast, a camera sensor has uniform pixel spacing on their sensors so they have similar resolution throughout the image they generate. If we assume we are just talking about the high resolution from the very center of our eye (average 147,000 cone cells per square mm), then we have a 655.6 pixels per inch (PPI) resolution at 10 inches (smartphone distance), 273.2 PPI at 2 feet (laptop, computer monitor distance), and 96.0 PPI at 5.7 feet (TV distance). Source: URL_1 It's very possible to create a camera with higher resolution than the human eye. A camera includes the lenses. If you've ever looked into a microscope, you're looking at higher resolution than the human eye since you can see things not possible with the naked eye. Replace your eye with a camera sensor, and you can generate magnified images due the lenses collecting light from a small area and expanding it. We can clearly see images of high resolution microscopy image and other imaging methods. They just expand the size of the image to something we can see! Going the other way, telescopes let us see further than the resolution of our eye. What looks like tiny dots in the sky get expanded to planets, stars, and galaxies with telescopes. Now, if you are talking about having a camera sensor better than the human eye, we have done that too. We just need a camera sensor with a higher pixel density than 147,000 pixels per square mm. Canon has already done this with a 418,000 pixels per square mm sensor: URL_0 . EDIT: Should be pixels per square mm instead of PPI in the last paragraph."
],
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"https://en.wikipedia.org/wiki/Fovea_centralis#Angular_size_of_foveal_cones"
]
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|
6w1dz6 | If monopolies are illegal, why are ISP's allowed regional control over huge areas so there is no competition? | Repost | explainlikeimfive | {
"a_id": [
"dm4l3na"
],
"text": [
"> If monopolies are illegal They're not illegal. Businesses are allowed to be monopolies as long as they follow certain rules. the biggest rule is that they cannot prevent competition. So in your case, Century Link owns the cable running to your house, so if another company wanted to compete, they'd have to lease lines from century link and then sell you century link, but under their name (which will cost more than century link)."
],
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|
6w3qc9 | How does the blowing part of CPR work if we are really just putting CO2 in their lungs? | Repost | explainlikeimfive | {
"a_id": [
"dm548kg",
"dm5493l",
"dm54912",
"dm55vqj"
],
"text": [
"Only a small portion of the oxygen that we inhale gets replaced by carbon dioxide. When you exhale, there is still plenty of usable oxygen left in the breath you took. It's certainly a lot more than the nothing that they are getting otherwise!",
"What you exhale is primarily oxygen rather than CO2. (It's mostly nitrogen, actually.) You don't use all of it up when you breathe in. In an enclosed space with a limited amount of air the percentage of CO2 in the air would just gradually rise. So when you perform CPR, you are blowing oxygen into their lungs and helping it circulate throughout the body. In a hospital setting, sure, it's better to have a nice feed of air highly saturated with oxygen--but what you do in CPR is a lot better than nothing.",
"Your lungs do not process most of the oxygen that goes into them generally. There is still a large amount of oxygen in exhalation.",
"Inhaled and exhaled air are both 78% nitrogen. Inhaled air is about 21% oxygen and minimal CO2, while exhaled air is maybe 14-18% oxygen and 4-5% CO2. By comparison, while the air in certain inhabited parts of Peru or Tibet is still 21% oxygen, the air pressure is only 55-60% of what it is at sea level. On top of Everest, we're down to 30% of sea level pressure. And sure, that excess CO2 isn't ideal, but when the alternative is \"literally no breathing at all,\" exhaled air starts to look pretty good. Big picture, though: The blowing part of CPR is way less important than chest compressions. The current rules for non-healthcare providers are to do compressions only, because breaths are confusing and kind of gross. What matters most is consistent and deep compressions given fast enough. Even bigger picture: CPR is for people who are pretty near death. Outside a hospital, 10% will survive another month; inside a hospital, maybe 20% will leave the hospital alive."
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6w4s4r | what exactly is fire? | Repost | explainlikeimfive | {
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"text": [
"Hot gas. There is a principle in physics called black body radiation. It says that if you heat up anything enough, it will begin to glow in visible light. This is why a hot iron glows red/white. This is why fire glows as well. The chemical reaction making the fire makes the heat, the heated gas makes the light."
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6w4sme | how come we never remember falling asleep? | Repost | explainlikeimfive | {
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"Exactly this is know as Sleep-related retrograde amnesia and here is a simple explanation: > The occurence of sleep appears to close the gate between short-term memory and long-term memory. All information in short-term memory storage at the onset of sleep apparently fades away. Accordingly, although one is unequivocally aware of the environment (perceiving) before falling asleep, these perceptions are usually lost from memory because they are not transferred into more permanent memory storage. > [Source]( URL_0 )"
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6w53mp | How come when, in the Middle Ages, people drank ale/beer instead of water because the water was too contaminated to drink yet they didn't all have foetal alcohol syndrome? | Repost | explainlikeimfive | {
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"The 'beer' they drank was not like the beers of today. It was probably around 2% alcohol. It also wasn't the only thing they drank by a long shot! You might want to check out /r/Askhistorians, as I know I've seen this same question there. Here, for example, is a nearly identical question: URL_0",
"1) They drank weaker beer most of the time. The kind of beer that drank a lot was called morning beer, small beer, and other names. It was roughly half the alcohol content of modern beers, and a third or quarter of some of the stronger ones today. 2) They likely did have fetal alcohol syndrome. The infant would have likely just been among the large number of infants that died. The thing to remember is that just because an illness does not get a diagnosis and name till modernity does not mean it did not exist in history or that it exists more now. It just means that we did not know what it was and either called it nothing or called it something else.",
"The entire \"drinking beer instead of water\" thing is a myth. Beer isn't strong enough to kill bacteria, so they needed to get clean water anyway. In many European villages, you'll still find the remains of wells that they used to get perfectly clean drinking water, usually located in some sort of gathering place in the middle. In some places, ground water was even shallow enough to just dig a well for every home. They didn't just drink the water from dirty streams, ponds or puddles unless they didn't have a choice."
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6w5b9y | Why do trips seem to last longer while going than while coming back? | Repost | explainlikeimfive | {
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"I feel like it's more because of the anticipation/ possible fear of actually reaching your destination. After you arrive and do what you're there to do I'd say the journey back to where you came from is spent more thinking about what you did. Example: An 8 year old on its way to Disneyland (no sponsorship intended) all excited and hyper thinking about all the things it'd do so the anticipation is killer. But I'm not a psychologist 🤷♂️",
"I read about this on Lifehacker. Here is the link to the source article on Washington Post. URL_0",
"I encountered this effect while doing longer marches. If you know the area your are travelling through it seemed to take less time."
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6w71pa | Does taking medicine that relieves symptoms (cough syrup, aspirin, etc.) help or hinder the body to overcome its ailment? | Repost | explainlikeimfive | {
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"It depends. Taking Tylenol or Aspirin to stop a fever hasn't been shown to make you sicker any longer. If you have a cough because of irritation and frequent coughing makes it more irritated, then suppressing the cough actually helps. For most people, a cough is just part of an acute illness and suppressing the cough doesn't make a difference except help you feel better. For people with chronic lung diseases, sometimes making the cough more effective will help clear out their lungs and suppressing the cough is *bad.* For most people in most situations, taking cough medicine or Tylenol or NSAIDs for fever will not help or hinder you getting over the problem. Keep in mind this is just for symptom control. Other medications are obviously very important and do good stuff. Even Aspirin, when it's used for it's antiinflammatory properties or its antiplatelet properties (and not just fever/pain) helps a great deal."
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6w7w96 | How much money is being made from the Floyd Mayweather vs. Conor McGregor fight/event? Who is that money going to? | Repost | explainlikeimfive | {
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"Mayweather is guaranteed $100MM, McGregor $30MM. The event is sold out, though I don’t have revenue numbers for that. Tomorrow (or maybe next week) PPV numbers will be released, which will be a major chunk of revenue, at ~$100 per household, and thousands of dollars for every bar and restaurant that shows it (actual cost is based on the number of seats in an individual establishment). I don’t know how proceeds are split but ticket sales and PPV are where most of the money will come from. Edit to add Mayweather is his own promoter (I believe) and UFC (or one of their entities) is promoting McGregor.",
"depends on who you ask... tomorrow we migh know. mayweather is expecting about 400 mill, mcgregor will be paid 100 mill afaik. the ufc is surely up for some grabs, but i dont know if thats for certain. the fight is put on by mayweather productions, so most of the profit will go to floyd, but he also had to pay for the venue and so on"
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6w8fhn | How did last names become a thing and how were they chosen? | Repost | explainlikeimfive | {
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"First names are quite easy to understand as people need a way to distinguish each other in a family or a village. But as communities grew larger you could get people with the same name or you may not know the first name of everyone. However this was not a big problem as you could just use a descriptive word or two. For example William the Brownsmith, George from Hilltown, John Peter's son. But as communities grew larger and people moved to big cities these descriptions became less of a description and more of a name."
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6w8nwu | If we are clean after taking a shower how exactly do our towels get dirty? | My niece was asking this question last night. I didn't know the answer to give. Her mom seemed completely uninterested as usual. So I would like to supply her with an answer. Any help is appreciated. | Repost | explainlikeimfive | {
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"When you dry yourself off, you're rubbing off dead skin & natural oils from your skin, leaving behind food for bacteria. The towel is then hung up damp, creating an environment where mold/mildew can start to grow.",
"If hung to dry somewhere with good circulation you can get multiple uses, otherwise the trapped moisture turns mildew-y",
"Dead skin cells that are sloughed off. To prevent moldy smells, I only buy white towels and sheets. Wash them with laundry detergent and a small amount of bleach and they always have a clean fresh smell."
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6w9rk5 | When hunting, what's the point of wearing camouflage if you're just gonna wear a bunch of bright orange stuff along with it? | Repost | explainlikeimfive | {
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"Deer can't see color, people can...its supposed to keep you from getting shot by another hunter",
"* game can't see that shade of orange, but people can * game can see shapes, which camouflage helps obscure",
"The point is to break up the human shape with different shadows (or what looks like shadows) and such in various shapes like what is natural in the background environment you are hunting in. Most animals that we hunt are color blind and cannot see the color orange so that is not an issue, but the human shape is an issue. So you want to look like the forest background, or grassland background, etc to blend in and break up your human shape.",
"In Wisconsin, blaze orange (and now pink) is worn during deer season as well as upland bird hunting(pheasant and grouse). This is done for visibility. That said, it often helps to have patterns in the blaze orange (camo patterns or black stripes) to break up a silhouette. Some states require a minimum Sq ft of unbroken blaze. Waterfowl and turkey hunting typically does not require blaze. Most birds have incredibly good eyesight and can see some colors so it is essential to blend into your surroundings to the point where your camo patterns should match your natural patterns (spring and fall forests, snow, reed canary grass). TLDR: the camo patterns with blaze orange helps break up a silhouette so while the game may not see orange, they don't see a solid grey blob.",
"For upland game birds (e.g. Pheasants, dove, quail) wearing orange prevents you from getting shot since to hunt them you commonly see people hunting in groups and the birds they have to be flushed from usually tall grass and bushes, so camo is not really a necessity. However, since a lot of camo gear can have water resistance and are good in cold weather you will commonly still see hunters wearing it since its practical for morning cold weather....and probably where you will likely see hunters wearing camo that absolutely doesn't match the environment because it's not a big deal. For waterfowl (geese and ducks), you are going to be stationary so the risk of getting shot is minimal, and iirc if you aren't in full camo without orange the birds will not fly in. Orange not really a necessity, but typically a camo pattern resembling reeds is. Turkeys can see color. They are one of the smartest things you can hunt, but then if you're everyone's favorite dinner you evolve to be smart af. Wearing camo and likely sitting in a pop up blind is likely going to be the only chance you have at drawing them in close enough. You cannot wear orange because the bird will know what's up. Makes a risky hunt if other hunters don't know where you are. For larger game like deer, yes most can't see color but they really can differentiate between the black and white and gray shading they see on the world, so camo that matches the geography around you is needed- woodland pattern in woodlands, sage for high desert, etc. typically one can also have orange intermingling in the design of some of the camo, but you'd also hope if someone is targeting a deer they've got a scope and are looking at their target, knowing not to shoot you if you are not wearing orange. TL;DR- geography and the animal being hunted determine necessity of orange, or a particular pattern of camouflage.",
"It can be any color as long as it's not solid. I hear it's because color blind animals see pattern disruption more easily. My history teacher told us colorblind soldiers could spot hidden enemy snipers in ww2 more easily if the sniper had a solid color uniform on which is why they were usually put in a scouting role but I'm not sure if that's true. I know turkeys can see color and wearing certain colors can make them fear or want to assault you. Reds and blues I think.",
"Dad and I wore jeans, flannels, and bright orange vests forever. Never stopped us from filling our tags. I think a lot of what I see is just men trying to play commando.",
"Follow-up: When hunting sure, but what's the point of wearing camouflage if you're just gonna wear a bunch of bright stuff along with it *in the military*? URL_2 URL_1 URL_0",
"Seems to be that it's because of outdated information. Most recent articles I could find (a few years old and from newspapers) indicated that deer are RG colorblind. So they can see orange, it just looks like a shade of red.",
"the very unpopular truth is that its pointless. people LOVE their camo and feeling like they are doing every little ritualistic preparation to enhance their chances of success. the reality is that people have been successfully hunting for thousands of years before expensive camo patterns were invented. deer are not people, they are not looking for the silhouette of a person, hell they likely dont even know what a person is. They do, however, understand movement, sound and scent, any of which can put the animals on edge.",
"Turkey : great eyes. No orange required when hugging. Deer: No orange needed for bow hunting, and you probably gun hunt in a blind unless your driving or something. Duck/ waterfowl : no Orange required. Upland bird: orange needed to not get shot in the face. At least in michigan. By its so thick the birds can't tell.",
"Like others have said, many animals can't actually see colour. This is where the \"5 S & M\" of stealth come in: * Shape * Silhouette * Shadow * Smell * Sound * Movement If you can stop any of these appearing human then it increases your chance of not being detected by said animals.",
"There's two kinds of hunting: big game and quarry. Big game are often things like deer and elk. Quarry are smaller things such as rodents and birds. Both kinds have very different quality of vision. Big game tends to have terrible vision - so bad in fact that entire parts of the spectrum are missing. They rely instead on sound and smell. Quarry on the other hand has VERY good eyesight and will see you coming unless you try to blend in visually with your surroundings. For this reason you want to wear things like [RealTree]( URL_0 ), as quarry has a hard time determining your size, position, shape and even existence when you're fully dressed in this. When you're hunting one of the most dangerous risks is being shot by another hunter. For this reason hunters wear blaze orange, a colour that deer and elk are blind to. Nobody wants to be completely dressed in orange though, so for the rest of a hunter's outfit they'll try to blend in. That means it's OK to wear camo and orange, but bright blue would be a problem. For this reason you see hunters in camo putting on blaze orange vests. Being shot by other hunters is such a big problem that here in NZ we have rules such as \"completely identify your target - do not rely on sight, sound or movement alone.\" There have been many cases of hunters carrying deer they have killed out on their backs only to be shot because someone thought it was still alive. A common thing to do is to wrap the antlers or dress the deer in an orange vest. Hunters feel slightly better about blending in with the surroundings when it comes to quarry because the calibres are smaller or they use birdshot. It's much easier for another hunter to tell a disguised human from a bird as well. In fact, when you're hunting quarry the most dangerous aspect is still other hunters, but the risk is generally from other hunters not checking their field of fire. What may be beyond their target, or the risk of ricochets from hard surfaces and water, etc. When hunting ducks for example there will be many hunters positioned around a lake - for this reason it's illegal to shoot at birds on the water as you may ricochet or shoot another hunter across the lake directly. When discharging a shotgun at quarry you must be pointing at a bird in flight.",
"You wear orange when deer hunting because they are color blind, but you have to wear camo when hunting turkey because they can see colors and can see you.",
"Camouflage is needed to obscure the edges of your outline so that the animals can't make out a figure. The orange portions don't compromise that.",
"Camo breaks up the human sillouette even if they seen colour the exact same way we do, they would see a bright colour and think for a second or two if they want to run or not. They dont see things like we do, and thus the reflective vest isnt a big factor. Tldr: camo breaks up the human silloutte which is why it works.",
"Hunter here. I think non-hunters fail to recognize how much of a fashion show hunting is to some guys. If you go hunting but don't look the part, your Facebook selfies will be terrible. Not everyone hunts because they love the outdoors and prefer organic, humanely-raised meat; for many it's about selfies, shopping for gear, and playing dress up. For my part, I wear camouflage for duck hunting because I don't hunt from a full blind. For deer and upland birds, I just wear whatever is weather appropriate and an orange vest or jacket over it. Then again, I don't have a Facebook page and don't take selfies.",
"Theres many good answers here so far. Another point that I didn't see mentioned is that many people will wear blaze orange to walk to their stand, and again later to walk out. But when they are in the tree or in a blind, they take it off.",
"Many have answered it, but here is a real life example called \"Dazzle Camo\" Look at this ship: URL_0 See how its outline is obscured and it's awkward. If it were one flat color it'd be easy to gauge what it is. So the camo outline help break up the shape of the person.",
"Some animals see the orange, so for them you wear just the camo, mostly bird I believe. Other animals cannot. The method of hunting also dictates the need for additional bright colors. If there are deer hunters in the area you definitely want to be visible, because they may be shooting a long range weapon at an animal and not see you in the brush behind it. I believe this may also be why rifle season is outside of the season of other small game, but that is just a guess. As for someone who only hunts in bright orange, its just not really made, partially because it looks silly, partially because you can buy a 200$ pair of insulated coveralls and a 10$ hat/vest and get an outfit for both situations instead of buying two sets of coveralls.",
"I wear it because it's equipment clothing, has extra pockets and I don't care if it gets dirty. You could wear a nice pair of jeans and shoes, but why risk ruining nice clothes?",
"there is no point to camouflage in 90% of hunting. in most cases the animal can't differentiate between the colors, or you're up in a tree where they won't look anyway. deer walk right past the brightest colored objects you've ever seen(like road cones with hazard lights blinking on top of them), and they don't care. simply holding still is an order of magnitude more effective than the best camouflage ever made. if you're holding still they won't notice you. they can see you but to a deer you're just another non-living object that's no threat. you could be cosplaying as an overwatch character with blinking LEDs and they wouldn't care as long as you held still enough. the reason people buy it is the same reason they by a special set of clothes for whatever else they're doing. hiking, running, whatever other hobby all have costumes associated with them. camo is the costume for hunting. but that's all it is.",
"Bow hunting is often done within very close distances to the prey. Say, stalking a deer and trying to come within 40 meters of it. You need all the stealth in the world on your side for this. You need to be in full head to toe camo for this. For hunting with a rifle however, you can engage as far aways as you can accurately shoot. Maybe out to several hundred meters. You may see what you think is a deer in the binocs, put them down, pick up your rifle and place the reticle on whichever moving target you find first. If a hunter in the distance is wearing full camo, they may inadvertently become a target in this scenario. The other hunter may have been stalking the deer from the other direction. Especially if the wind ended up in his favor. Had they worn orange, even just a vest, or orange gloves, or a hat, it would have been more obvious. Accidents happen occasionally when a hunter is on his private property, and is shot by another hunter either aiming into property which is not his, or is straight up hunting illegally on someone elses land. Tl:dr Using camo is sometimes entirely necessary (walk and stalk with a bow), and other times entirely unneccessary (rifle hunting, at longer distances). PS, Something else important to note, bullets are cheap, and arrows are expensive. Rifle/shotgun Hunters have been known to get trigger happy and the more bullets put down range, the better chance that one hits something it shouldnt. And from the shooters perspective, more bullets down range equals a high chance of hitting the intended target. PPS, ALWAYS KNOW WHAT LIES BEYOND YOUR TARGET, AND NEVER TAKE A SHOT IF YOU CANNOT GAURANTEE YOU WILL HIT WHAT YOU ARE AIMING AT (beyond a reasonable doubt, at least, no one is 100% accurate)."
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6wb0oc | why do American trucks (an extended nose containing an engine) and European lorries (flat face engine under the driver) look different? | Repost | explainlikeimfive | {
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"Most countries in the world have regulations defining the size of vehicles that are allowed to use their roads. This is necessary so that they can plan junctions, bridges, and so on. In the EU and other European countries, the law defines the maximum length of a truck to include both trailer and cab. In North America the law only defines the length of the trailer. Long-nosed cabs are generally cheaper to build and easier to maintain, so in North America where the length of the cab doesn't matter this is the most common design. In Europe, where every additional metre on the cab's length means a metre less available for the trailer (and hence fewer goods transported and therefore less money being made) the snub-nosed cab is the one that's usually used.",
"This is not just a US vs EU thing, there are flat nosed trucks in the US/Canada too. A flat-faced truck is called a \"cab over\". A big advantage of cab over designs is it decreases the overall length of the vehicle, which reflects places and/or times when there were laws regarding length of the vehicle. more at URL_0"
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6wbi5v | Why do most men go bald, in spite of all the testosterone? | I'm 25, I have a full beard, I have new hair coming out on my back and shoulders but the hair on top of my head have started falling. What's up with that? Are the rules different for that part of the body? EDIT: What the hell? Ads about hair products started showing on reddit. Ads do get smarter. | Repost | explainlikeimfive | {
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"Testosterone gets converted in the body to something called DHT (dihydrotestosterone) which is useful for many important things in the body. People have different types of hair folicles and The ones on our head are actually different to the ones on our body, they have a much longer growth cycle and are sensitive to DHT. DHT binds to the hair follicles on the head which makes them weaker and with every growth cycle, the hair will grow thinner and thinner until it can no longer penetrate through the skin anymore. Hair loss medications use a form of DHT blocker (finasteride, Azelaic acid, etc) combined with other stuff to free the weakened hair follicles from DHT and allow them to regain some or all of their strength. body builders, athletes and other steroid users who inject testosterone also end up increasing their DHT levels because there is more test to convert. This is why hair loss is a common side effect of anabolic steroids.",
"It's because of a genetic mutation that causes a specific area of the scalps follicles to be sensitive to DHT - a preprogrammed pattern. It takes a long time for the follicles to respond to the onset of it but eventually it gets ya. I am bald on top and it actually initially started with me when I was 17 at the very edges of my forehead! So minor it was back then, but 18 rolled by and it wasn't too bad, then 19 it got slightly worse, creating the more defined M shape (no spam at the back first, thankfully), then 20 it progressed quite a lot on the tops of the left and right of the forehead and by 21 it got so bad at the left and right of my forehead that I started shaving my head completely. Realistically I could have just had short hair but meh. Through 21 to 28 it thinned out on top completely so I now have the definitive horseshoe shape if I don't cut my hair, but I shave my head completely anyway. If I run my hand across my head through the middle there is still a quite a few bristles but no where near enough to grow it - I am fortunate my hair is a mousy blonde colour so it doesn't show as much. Fortunately I don't look too bad bald/shaved and kind of suit it. Some people are very unfortunate and do not. So yeah, testosterone encourages hair growth, but a messed up genetic mutation is why a predetermined pattern of weakened hair, sensitive to DHT is why we lose it. Like all of these things, just like other genetic inheritance of, say, diseases, the onset is unknown but expresses itself within a certain time frame - this is why some of us get hair loss at varying times, some very late, some super early (like me). For example; my Dad is bald and his Mother, who he heavily takes after, her father was bald. I take heavily after my Dad but he had decent hair till his mid 20s, I didn't. It was a lot more pronounced on my forehead earlier on than on my Father. My Grandfather, who I don't take after much, is bald but that didn't affect him till his 50s. So the genes are all there. My Brother however takes heavily after my Mother, whose father isn't bald nor is my Mother's father (as far as I am aware). So while my Brother is whining about his receding hairline at the corners, left and right of his forehead, and has been moaning about it for years, his hair receding is so minor it seems to me, ridiculous. My brother is 9 months younger than me and he has almost all of his hair. He is at the stage I was at 19/20! (We are currently both 28, but I will be 29 in February). Blah, rambles. My apologies. A lot of shit will happen if you cherish your locks... Or not. Look at your family history and try not to worry too much. There are ways of slowing hair loss, even if it is genetic Male Pattern Baldness (MPB). However do not go spending fortunes on trying to cure the inevitable. There are cost effective solutions that can slow the process but it isn't a guarantee for everyone. Or, you may be lucky and it may not progress heavily till you are older. You may experience a roller-coaster of emotions or you may be more chilled about hair loss like I was. There will be moments in your life where you get pangs and thoughts or wishes of having hair or doing something about (transplants, research, etc) but the best way to be is to be accepting of yourself and not trying to please everyone else. My brother once told me that the new people you meet will not find you ugly or weird looking because they have only ever seen you with your head shaved... So yeah that helped me when I had my doubts about going out. If you are worried and it appears to be progressive, instead of clinging on to hair like it is all there is to life, experiment with shorter hair styles gradually over the years until eventually cutting it to 0.5mm with a trimmer - this means it is a less drastic or shocking change to people you are around rather than going from longish hair to slap head, because stark differences, whether it be hair or anything else is always going to draw attention. You don't have to go cue-ball style. In fact, I never even started using a razor on my head until a couple of months ago! You really don't need to use a razor. Short and tidy 0.5mm hair will show a faint outline of where your hairline is, but because it's very short it looks good, not old man style. Embrace le bald when the time comes, it is not as bad as you think. All the best dude. Remember, don't worry! (งツ)ว (Edit: added info, corrected mistakes - forgive me, I was having a hypo :D)",
"I was reading an article about fecal transplants the other day and found an interesting anecdote- apparently sometimes bald men who have fecal transplants start growing hair again. It may turn out that it's much more complicated than we think. Found the article- URL_0",
"Men go bald *because of*, not in spite of, testosterone. DHT is a similar hormone to testosterone.* How much free-circulating testosterone, and how much free-circulating DHT you have in your blood determine a lot of things. Male hormones are often spoken of in terms of how anabolic and androgenic they are. Anabolic basically means binding to receptors in muscles and making 'em grow. Androgenic basically means binding to receptors in other tissues and making 'em do other man stuff. DHT is somewhat anabolic, and much more androgenic than testosterone. When it binds to hairs, it makes them convert from baby-soft, lighter, finer hair type, to old-man, darker, thicker type. DHT is also mostly responsible for the progress of male pattern baldness, thickening and darkening of facial hair, chest hair, and pubes. Here's a source talking about how male pattern baldness may be related to some sort of disorder with DHT: URL_0 EDIT: DHT is *not* \"basically 2 testosterones hooked together\".",
"My understanding is that hair all over the body has different responses to testosterone (especially when it gets converted to DHT that causes hair follicles to fall out). Beard hair tends to grow more with more testosterone but hair on the crown (front hairline to the the “bald spot” area on the back of he head) tends to fall out due to DHT. Facial hair and hair around the side and back of the head is more resistant to DHT and therefore doesn’t usually fall out (leading to the old man hair we usually think of, i.e. bald on top and front but hair on the side and back of head). This is why hair transplants tend to pull hair roots from the back of the head since they are more resistant to DHT. I started seeing my hairline recede when I was 24 and I started using minoxidil (Rogaine) and it helped me keep most of my hair. The sooner you start treatment the better the results, but you have to keep using for the rest of your life or it will start to fall out. Minoxidil and propecia (proscar) are the only FDA approved drugs to treat hair loss. Everything else out there has yet to be medically proven to work. Fun fact, hair lost isn’t actually “dead” but is just in a really long resting phase. Your hair is constantly going from growing, falling out, resting then growing phases. Eventually your hair just rest permanently then you have balding in that area.",
"Male pattern baldness is related to a sex-linked recessive gene, and not really tied to the rest of your body since that's other genes. What does that mean? When your parents love it up and make you, two sex chromosome are passed on. Women always pass an x (because they're xx) and men can pass an x or y (because they're xy). The gene that tells your body \"Hey, don't go bald please\" sits on the x chromosome. If you're male, you only get one x chromosome so you only get one chance that you have this gene buddy looking out for you (that's the sex-linked part). If you're female, you have two chances so if one x is saying \"Hey, go bald\" and the other is saying \"Nah, we ain't doing that\", the latter takes over (that's the recessive part, since it takes a lack of \"don't go bald\" instead of a presence of \"go bald\" to happen). So, if you're ever worried if it's going to happen to you, it always helps to look at your mother's family history.",
"- 95% of balding is due to Androgenic Alopecia, a hereditary gene. You can get them from either your Mother or Father, not just the maternal side as one myth is reported. The other 5% is often due to underlying health issues like Thyroid problems, Stress induced hairloss (Telogen Effluvium) or other conditions called Alopecia Areata, Alopecia Totalis. - Classic MPB (Male Pattern Baldness) comes normally in two forms. One is the ‘’classic’’ type where you see a recession of the hairline at the temples into a deep ‘M’ shape followed by a bald spot at the crown (around where your cowlick can be). The bald spot often gets bigger and bigger until it joins at the hairline. These are examples of more extreme baldness where the spot meets the hairline and is normally classified under the Norwood hairloss scale as types V, VI & VII. The other type of male hairloss due to genetics called diffuse hairloss. There is not often a recession of the hairline at the temples but instead the whole top goes out over time. Reports have said this is generally a more aggressive form of hairloss but the severity of the hairloss is generally more down to the individual and their genetics. - A link to the Norwood hairloss scale: URL_1 - Hairloss in women comes under the Ludwig scale and ‘’generally’’ follows a different pattern to men where the centre parting of hair gets wider and wider. - A link to the Ludwig hairloss scale for women: URL_0 - Hairloss is down to your genetic sensitivity to your own hormones. Everyone, man and women but men in higher quantities have a hormone in your body called DHT (Dihydro-testosterone). It is a far more potent form of Testosterone and gives men their male characteristics such as deep voice, body hair and formation of male genitalia. It is produced in the Prostate, Testicles, Adrenal Glands & Hair Follicles. - People say that it is high levels of DHT that cause baldness or high levels of Testosterone but this is incorrect. It’s actually how sensitive you are to your own hormones and how many receptor you have in your existing hair follicles. You could have incredibly low DHT levels but a lot of receptor sites in your hair follicles thus becoming bald or incredibly high DHT levels but if you have very little DHT receptors in your hair follicles then you likely won’t go very bald or at all. Also a myth exists that men who go bald have more testosterone, this is also not true. It's all down to the individual. - People believe there are other causations and reasons for balding but the DHT theory in combination with chronic but low level inflammation in the scalp (which is why your scalp can itch) is generally the most widely accepted. There is other things regarding KROX-20, WNT pathways, PGD2 and Lactate production but I won’t get into them. They are still being debated and until we have more evidence people generally just tackle DHT as the primary culprit. - At the moment the only two FDA approved treatments for hairloss is Minoxidil (Rogaine, Regaine, Kirkland etc) and Propecia/Finasteride. However, both are life long commitments and can come with side effects. Minoxidil is a vasodilator meaning it increases blood supply to the area it is applied. Some people manage to maintain, a lucky few grow some hair back and an unlucky few actually lose hair. Other reported side effects are dark circles under the eyes, shortness of breath, heart palpitations and even aging of skin due to it (allegedly) inhibiting collagen production in the skin. - Propecia/Finasteride first patented by Merck for BPH (Enlarged Prostate) until they discovered it could stop or slow down balding and now produced also elsewhere by other companies is an oral medication that stops the conversion of Testosterone into DHT by blocking the mechanism 5-AR. Some people report good results and maintain or even regrow some hair however in recent years a lot of reports side effects (primarily of a sexual manner) but also of a psychological manner have surfaced. Merck claimed 1-2% of men got these side effects but other studies say it is far, far higher. These side effects can include testicle ache, weak or useless erections, watery semen, loss of libido and depression. Merck claims all side effects should stop once the drug is stopped but some individuals report side effects lasting months or years after cessation. There is a longer list but I will not get into them. I had side effects for 16 months. I was on it for 3 weeks. - Finasteride/Propecia is often prescribed by a Doctor. It generally comes in a 1mg pill which is to be taken daily but some people take 0.25mg every day or up to 1.25mg every day by splitting the 5mg pills into quarters. 5mg is generally used for enlarged prostate. Propecia/Finasteride stops the conversion of Testosterone to DHT by up to 70%. Whilst people are still not completely 100% the reason a lot of men (but some don’t) get side effects is because they are decreasing their primary male hormone by a large quantity. This medication should not be used by women and ideally not men who have not finished developing (18-21). - There are other things that can stop or prevent hairloss but they are likely not very effective. There is a lot of fake and phony products on the market that exist purely to take money from them. Please please do your research before purchasing hairloss products. Forums are easy to find and so is the information. - There is also HT (Hair Transplants) but they can be expensive, ineffective or give a very un-natural look plus there is alot of dodgy HT doctors out there so DO YOUR RESEARCH should you choose to go down this route. Also alot of Doctors recommend you take Propecia/Finasteride after a HT but if you had side effects or don't want to take medication the rest of your life HT can be only a temporary fix before you lose more hair. - Upcoming treatments: Science is advancing at an incredible rate but a lot of people complain that we are yet to have a safe cure for balding. I will not go into great detail but there is currently many companies who are working on alternate treatments. There is big $$$ to be made. If you are reading this and are particularly depressed about going bald here are some companies or upcoming drugs you could look into; - Replicel/Sheseido - Tsuji Hair Cloning - Brotzu Hair Lotion (FIDIA) - JAK Inhibitors - Follica - Follicum - Rivertown Therapeutics - Allergan (Setipiprant) -Fevipiprant (for asthma but some evidence theorises it could be very effective for balding) - Why does curing hairloss even matter? A lot of people say we should be curing things like Cancer, HIV, MS, Dementia and Diabetes instead of hairloss but currently we are trying to cure all that are listed and hairloss. Just like women deserve a safer alternative to the pill (messing with hormones is not safe alot of the time, the balance is very delicate) men and women also deserve safer alternatives to hairloss. - Some people go bald and it’s not a big deal, they own it and look great and honestly I say absolute power to you. However, many young men and women (typically who go bald faster as it begins earlier) find balding very destructive to their self-esteem and confidence. We live in a world now where vanity is becoming more and more prominent. Not only that but losing hair, particularly at a young age can destroy ones confidence. Especially when you are in the process of discovering who you are. On top of that there is also a stigma against men wearing wigs but not against women and if men are discovered they will often be ridiculed or called ‘’shallow’’ or ‘’vain’’. - I hope this post has cleared up some information. If anyone notices corrections please feel free to comment and I’ll adjust the post accordingly. I tried not to be biased too much but as a young individual losing their hair fast and young it’s a hard burden to carry, particularly when conventional treatments did me more damage than good. Oh and inb4; - ‘’Just shave it and hit the gym’’ – Some of don’t want to be ripped. - \"Some girls/guys love bald guys’’ – Great but some of us don’t love being bald guys. - Any comments regarding Jason Statham, Vin Diesel, The Rock or Patrick Stewart. These men are the exception but we are bored of seeing their names in every hairloss thread. Myself and many others don't aspire to be this men. We merely aspire to be comfortable in our skin. - \"Get over it, it’s only hair’’. Ok, let me remove your favourite feature of your body and then get over it.",
"I'm the only guy in my family who is not bald. I'm in my 40s. At Thanksgiving at the dinner table it is like sitting in an egg carton. Something must be hereditary but it is not a sure thing. Edit: people keep joking that I was adopted or it was the mailman. My mom says I wasn't and we got the mail from a community mailbox. Here is a picture of me with me two sisters and brother. I am wearing the overalls and have the red stripe on the soles of my shoes. [Pic]( URL_0 )",
"Do men who transition to female after having already gone bald regrow their hair? Do they at least stop losing more hair once they start female hormone treatments?",
"Thickness and amount of hair is not something you can look at to determine how much testosterone you have. Everyone has peach fuzz hairs and each follicle has a testosterone threshold that, when exceeded, signals the follicle to pigment the hair and grow longer/thicker. This threshold is a result of your genes. A man with a full beard could well have less testosterone than a man who can't grow a beard at all. Generally speaking, those with crazy thick/long hair just have a lower testosterone threshold to stimulate growth in the follicles. Edit: This doesn't quite answer your question, but I believe this information to be pertinent.",
"If I remember correctly, a running pattern amongst prematurely balding men is high testosterone levels.",
"DHT (dihydrotestosterone) is a downstream product of testosterone. DHT It is found in lower concentrations but is more portent than T. The hair follicles on the top of your head are more sensitive to DHT. Some people's are extra sensitive depending on their genes and they end up with complete hair loss in that area. The reason hair transplants work and don't immediate fall out is due to the choice of hair to transplant with. Public hair from your back is sensitive to DHT but in the opposite way. Its growth is promoted. Your hair loss is normal and is part of the normal growth process. Don't fight it with any DHT blockers and enjoy the added benefits at the gym and in the bed from the extra DHT you seem to be making now.",
"It's not \"most men\". There's a large genetic factor which plays out in multiple ways (i.e. levels of testosterone). However, it's a double edged sword. For example, I'm in my 30s and I've never grown a full beard, even after a month of not shaving.",
"Nobody knows why, but hair along the top of male heads reacts opposite-ly to the presence of DHT, a product of testosterone. Where body and beard hair grow stronger, in that one zone, dht causes inflammation m and the hair stops growing. Why that spot? Nobody knows. Why only men and not women ( even those who take testosterone )? Nobody knows. Edit: women get forms of baldness too, but not the pattern of no hair on top, hair remaining on sides that OP asked about.",
"You say \"in spite of all this testosterone\" as if you never heard of the term male pattern baldness. Your testosterone is turning to DHT and making you go bald. It is the testosterones fault.",
"Testosterone is converted to DHT. DHT acts locally on hair follicles. DHT *stabilizes* follicles of chest/beard hair, whereas DHT promotes the *degradation* of hair follicles on your head. So it's not \"in spite of,\" it's \"because of\"",
"Testosterone and its associated hormones can have drastically different effects on different types of hair follicles. Beard growth and body hair can be stimulated by extra testosterone, whereas DHT, a hormone made from testosterone by the body, is linked to the shutting down of hair follicles that results in male pattern baldness.",
"Genetics. Alopecia specifically is a trait that is carried primarily by men and leads to baldness.",
"Testosterone promotes the growth of body and facial, but it is actually the cause of male pattern baldness. Receding hair line, and such.",
"It's actually **because** of all the testosterone. Your body can start to metabolize testosterone as Dihydrotestosterone, which causes male patter baldness (loss of hair on your head).",
"Baldness is actually associated with testosterone; it's actually theorized that it's an evolutionary sign of seniority (like a gorilla's silver back) that is viewed in an entirely different light socially.",
"DHT causes the baldness, bro. It's in fact too much testosterone that causes male pattern baldness. Basically the reason you can grow a thick beard is the same reason you're going bald.",
"So scientists don't know exactly why male pattern baldness happens but, found it's cause to be from DHT (a chemical byproduct) from testosterone settling around the scalp. DHT strains the follicle productivity, causing hair to thin and eventually to stop producing. There are some remedies that can help however. Like drinking certain teas, essential oil application, and other ways. For another example there are also little tools like micro needle rollers that help too.",
"I don't know what the statistics are, but in my time working in nursing homes so far I've seen a lot of very old men who still had a full head of hair, though often it was thinner than when they were young. Pretty sure it's just genetic. I see a lot of bald heads too, mind you, but it's not so rare to see men in their 80's and 90's who still have their hair."
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6wcbsr | What is the chalk at the billiards table for? | Repost | explainlikeimfive | {
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"You rub it on the end of the cues to make the contact surface less slippery, so that more of the force of a stroke is transmitted to the cueball. Same reason gymnasts rub their hands in it when swinging on beams, to maintain grip."
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6wdmq6 | Why does extreme physical exertion sometimes cause vomiting? What is the body trying to rid itself of? | Repost | explainlikeimfive | {
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"i believe it has something to do with the fact that physical exertion diverts blood away from the digestive system and to the muscles, so it could be your digestive system trying to get rid of the food so it doesn't have to digest anything while you are exercising edit: spelling",
"While exercising, your muscles release lactic acid which in turn breaks down into Hydrogen ions, water, and CO2. The hydrogen is acidic and thus increases your bodies acidity level( pH).Hydrogen takes a long time to be removed or broken down by the body and so the only fast way to lower the pH levels in your body is to throw up the stomach acid ( hydrochloric acid) which contains hydrogen. This brings the body back down to an equilibrium where the organs cells ect can work in an optimal environment that is not too acidic.",
"When you run, especially if you're running because of panic, the body diverts blood from the digestive system and into the heart and lungs. The body then gives the command to vomit because that undigested food is weighing you down as you try to escape, and there is the chance that the predator might stop to eat the contents."
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6wdtza | How does wind works? Where does it come from? | Repost | explainlikeimfive | {
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"The sun heats up the land, also heating the air above it. Hot air rises (see:hot air balloons) when there is cooler air around it because it is less dense. The space left by the rising hot air is filled by cold air from the areas near it, and the movement to replace the hot air is wind. ELI10, the difference in absorbed solar radiation, the constant day night cycle, and the rotation of the earth create different, reliable wind patterns like the jet stream and trade winds. The cold air from the poles moves on the surface towards the equator, where it warms and rises and returns north, creating huge convection cells. There are also smaller ones in bands between the tropics. Everything circulates like water in a boiling pot, but with several systems operating simultaneously. The exact same principles apply to ocean currents. Tldr pockets of varying pressure due to temperature difference constantly try to equalize by mixing.",
"The sun heats the earth unevenly. Warm air and colder air move around because they are different temperatures. [Here are some threads from this sub on the ."
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6wecy7 | How can something be see through on one side but reflective on the other like a 2 way mirror | Repost | explainlikeimfive | {
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"The glass is coated with, or has encased within, a thin and almost-transparent layer of metal (usually aluminum). The result is a mirrored surface that reflects some light and is penetrated by the rest. Light always passes equally in both directions. However, when one side is brightly lit and the other kept dark, the darker side becomes difficult to see from the brightly lit side because it is masked by the much brighter reflection of the lit side. If you want to know how this works on a technical level, the r/askscience folks might be able to explain it. Here's the not very helpful wikipedia page on the subject: URL_0"
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6wf3ew | How are older films re-released in 4k resolution? | Repost | explainlikeimfive | {
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"Films on actual photographic film have extremely high resolution, limited only by the grain and state of preservation. To re-release in 4K, they scan it with a better scanner than they used for previous video releases, usually do some color correction, and release it."
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6wg7ds | Where did the "recommended by 4 out of 5 dentists" thing come from? | I mean I have never heard the 4 out of 5 thing been used outside of dentistry field. Where did this come from and why is it only used with dental hygienic products? | Repost | explainlikeimfive | {
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"The bullshit survey of experts is a marketing tactic that seems to have started in the 50s. Trident Gum's dentist survey (from the 70s) is certainly the most remembered (actual results: 4 our of 5 dentists agreed that sugar-free gum was *preferable to sugar gum*, 5th dentist said \"don't chew gum period\"). Other examples include [Whiska's cat food]( URL_3 ), [Camel Cigarettes]( URL_0 ), and, uh, [Chun King Chow Mein]( URL_1 ). It's easy to get a survey to say what you want - I understand that the Camel survey was included with a case of free cigarettes. And of course, you can just keep taking surveys or rephrasing questions until you get an impressive statistic. And apparently, [nine out of ten doctors would not recommend being a doctor.]( URL_2 )"
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6whkb3 | If I touch a puddle that has an electrical cable in it, I'll get shocked. If I throw an electrical cable into the sea, why will not everything in the entire ocean become shocked? | Does electricity 'dilute' itself in water? If I was close to the source of electricity would I get shocked then? How close would I need to be? Would the direction matter? Is there like a certain equation for how much electricity weakens by taking into account number of electricities and number of waters? | Repost | explainlikeimfive | {
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"When you are shocked it's from electrons flowing through your body. Electrons on a finite thing. There are only so many of them. The amount of electrons that can be drawn from the outlets in a typical building are way way way more than are needed to kill a human. However the Ocean is really really really big. Whatever powercord your throw into the ocean eventually leads back to a circuit breaker. The amount of electrons that can be drawn into the ocean depends on what that circuit breaker is rated for. Even if it's a huge break, say 600 amps, that's no where near enough to hurt everything in the ocean. Modeling something like this is tricky because there are a lot of things we don't know. To start with pure water doesn't conduct electricity. However dissolved minerals in the water do. The ocean is salt water and does conduct electricity. However the saltiness of the water isn't the same in every drop so some patches of water might conduct electricity better than others. If you compare the end of the electrical cable with the ocean, the cable will have a much higher concentration of electrons so yes, the closer you are to the cable the more likely those electrons will try to go through you and hurt you. So yes the voltage does dissipate with distance.",
"Yes, it spreads out, and some of the energy is lost to heat as it travels as current. When lightning strikes water, it will spread out in a hemisphere under the surface, the energy dissipating with the cube of the radius. You would certainly be shocked if you were close to where it struck, because you are not much different from water yourself, and the current would travel through you too."
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6wih9o | How do sex scenes in movies/tv work? | Repost | explainlikeimfive | {
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"Carefully selected angles and skin coloured underwear/thongs. Usually the crew will be reduced to the minimum so that the actors don't feel too exposed in their nudity. Unless you see the actual genital intercourse (as in porn) it's not happening. Just rubbing. Samuel L. Jackson said in an interview he always apologised beforehand to the lady in case he got hard. And also in case he didn't.",
"In addition to the above, Lars Von Trier filmed porn actors actually having sex and superimposed the actors heads on it in Nymphomaniac",
"It very much varies. Some scenes the director will carefully pick the angle, some will have a touch of CGI, some will use flesh coloured underwear. Others will go up to the actors actually being naked... And a small number... A very small number outside of porn... They will actually be having sex. Intimacy, and The Brown Bunny spring to mind for that last category."
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6wl9xn | Why is it easier to hit flies with a swatter than with your bare hands? | Repost | explainlikeimfive | {
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"dm8ueso",
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"Bunches of reasons. For one you can see that they are on a long arm which acts as a lever, turning a greater force over a short distance into a lesser force over a longer distance. This trades power for speed, and as your arm can exert far more power than is required to mash a fly but cannot move fast enough that is a great trade. Another reason is that the swatter is much less massive than your arm and hand which means it is easier to accelerate to fly-mashing speeds. Finally another reason is that the wide swatting head has holes in it which reduce the air resistance while still being closely spaced enough to impact the fly. Your hand is unavoidably solid so air must go all the way around it rather than through it. Flies also have hairs which allow them to feel air movement from oncoming objects such as predators and allowing most of the air to flow through the swatter reduces that warning to the fly. The combination of all those factors is a wide swatting head which can be moved far faster than your arm and hand, catching the flies before they can take off and flee.",
"Yo ho ho! Yer not alone in askin', and kind strangers have explained: 1. [ELI5: Why does a fly swatter work better than your hands? ]( URL_0 ) 1. [ELI5:Why does using a fly swatter make me so much more effective at killing flies? ]( URL_5 ) 1. [ELI5: Why is it easy to kill flies with a fly swatter, but hard to kill them with your bare hands? ]( URL_4 ) 1. [ELI5: How come it's near impossible to kill a fly with my hand but so easy to kill it with a flyswatter? ]( URL_2 ) 1. [ELI5: Why is it so much easier to kill a fly with a flyswatter or newspaper than with your hand? ]( URL_1 ) 1. [ELI5: Why do fly swatters work so well? If I try to catch a fly / smack it with my hand I can never get it. ]( URL_7 ) 1. [Why does a fly swatter instakill flies but when I hit flies with my hand it does nothing? ]( URL_3 ) 1. [ELI5: Why is it so hard to kill flies with anything other than a fly swatter? ]( URL_8 ) 1. [Why is it so hard to swat a fly with your hand but easier with newspaper? ]( URL_6 )"
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"https://www.reddit.com/r/explainlikeimfive/comments/3dqjce/eli5_how_come_its_near_impossible_to_kill_a_fly/",
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"https://www.reddit.com/r/explainlikeimfive/comments/1ls5pn/eli5why_does_using_a_fly_swatter_make_me_so_much/",
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"https://www.reddit.com/r/explainlikeimfive/comments/3b86wq/eli5_why_do_fly_swatters_work_so_well_if_i_try_to/",
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6wlmy4 | The Poincare Conjecture | This math problem was one of 10 millineum problems that were really difficult to solve, with a million dollar prize. One russian mathematician called Grigori Perelman managed to prove the conjecture which deals with the branch of mathematics concerned with topography. Someone please explain the Poincare Conjecture in layman's terms? | Repost | explainlikeimfive | {
"a_id": [
"dm8yozb"
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"text": [
"The Poincare Conjecture states: > Every simply connected, closed 3-manifold is homeomorphic to the 3-sphere. Let's break it down: *Manifold* - Basically this is just a topological shape.There are some general rules for what is and isn't a manifold, but if, when you zoom in, it could be flattened out, it's a manifold. *3-manifold* - This is how many dimensions we're working with. A point is 0-dimensions. A circle is 1. A sphere is 2. We're talking about a manifold with 3 dimensions. *Closed* - There is no boundary. Think of a sphere. You can walk along the surface of a sphere forever, without reaching an \"edge\" or end. Compare with a sheet of paper where you will. *Simply Connected* - Basically, there are no holes in our manifold. A sphere is simply connected. A donut is not. *3-sphere* - A special type of 3-manifold. Analgous to the traditional \"sphere\" (2-sphere) that we think of. A 2-sphere is every point equidistant from a center in 3D space. A 3-sphere is every point equidistant from a center in 4D space. *Homeomorphic* - A fancy way of saying that you can take one, change its shape (without ripping or tearing or breaking it apart) and turn it into a different shape. So, it's saying that you can take any three dimensional manifold that has no boundaries or holes and morph it so that it becomes a 3-sphere."
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6wmk58 | Why do some clocks with roman numerals use IIII for the number 4? | I have noticed that some clocks with roman numerals have 'IV' and some with 'IIII' for the number 4. why is this the case? | Repost | explainlikeimfive | {
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"It just the tastes of the clock maker. It's particularly common for clock faces to use IIII for 4, but still use IX for 9. The Romans weren't nearly as rigid about how Roman numerals were to be used as we are today when teaching people about them. IIII vs. IV, XVIII vs. XIIX, VIIII vs. IX... there's even examples of people using two different forms in the same document. It's just how they rolled.",
"The explanation I've heard is that IV is written the same as JU in old Latin script, which are the first two letters in Jupiter, the most powerful Roman god (analogous to Zeus). People didn't want that, either because they were superstitious pagans who didn't want to draw Jupiter's attention/wrath, or they were Christians who didn't want to appear that they were invoking the name of a pagan god in their homes.",
"The reason isn't completely clear, there are a number of possible explanations: * both the 4 and 6 are upside down, so IV and VI could be confused * IIII balances better with XIII at the opposite location * IIII allows for a round number I's, V's, and X's to be made for each clock * IV was not a universal usage, some Romans used IIII for 4"
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6wu7av | when in a moving vehicle how can an insect fly around freely without being sucked to the back? | Repost | explainlikeimfive | {
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"Inside the car, the air is moving at the speed of the car. It feels very different if you roll down a window and stick your arm out. The fly flys in the air, not the car. Since the back window of the car is pushing the air to move it forward, the fly is going from place to place at high speed but not experiencing the air drag (just like you)."
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6wusyq | How do instincts get passed on from generation to generation? | Repost | explainlikeimfive | {
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"Yarr! Yer not alone in askin', and kind strangers have explained: 1. [ELI5: How do animals like Ants and Birds instinctually know how to build their dwellings/homes? ]( URL_8 ) 1. [ELI5: How is instinct developed and passed through generations? ]( URL_6 ) 1. [ELI5: How are instincts inherited to the following generation and is it possible to modificate and/ or create them? ]( URL_9 ) 1. [ELI5: How instincts biologically work? ]( URL_0 ) 1. [ELI5: How is natural instict passed through the generations? ]( URL_11 ) 1. [ELI5: How the process of mimicking is passed on through certain species. ]( URL_10 ) 1. [ELI5:How do instincts work? ]( URL_7 ) 1. [ELI5: How does animal instinct works ? For instance, how does a spider know how to make a web ? ]( URL_4 ) 1. [ELI5:How do instincts work? ]( URL_1 ) 1. [ELI5: Do we have some kind of genetic memory, similar what is presented in Assassin's Creed? ]( URL_2 ) 1. [ELI5: How do we inherit survival or psychological instincts/traits? ]( URL_5 ) 1. [ELI5: How have instincts got inscribed into our genes? ]( URL_3 )"
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"https://www.reddit.com/r/explainlikeimfive/comments/2du2fr/eli5_do_we_have_some_kind_of_genetic_memory/",
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"https://www.reddit.com/r/explainlikeimfive/comments/2zw33c/eli5_how_are_instincts_inherited_to_the_following/",
"https://www.reddit.com/r/explainlikeimfive/comments/4l1m46/eli5_how_the_process_of_mimicking_is_passed_on/",
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6wyr9l | What exactly do physicists mean when they say the universe in expanding | Repost | explainlikeimfive | {
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"dmbpjg5"
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"text": [
"Over time, any two (significantly) distant points in the universe are increasingly far apart. There's more 'space' between them. This occurs at very large scales. For instance, our local galaxy cluster is gravitationally bound, and not expanding apart. To the contrary, we will eventually collide with another galaxy, Andromeda. But distant galaxies to which we are not gravitationally bound are all becoming more distant over time. An observer would see the same from any other location in the universe, everything distant from them moving away. > What is beyond the universe? Expansion is not meant to imply that the universe is something like a bubble, gradually filling up a greater volume. Rather, it is thought to be, although unproven to be, infinite in volume. Over time, it is becoming less dense. There's more space between objects. It is not known to be 'expanding into' anything, and we have no knowledge, nor at this time reason to believe, in an external volume which the universe is contained in or touching. As far as we have solid evidence for, the universe contains everything that exists.",
"the spaces between everything are essentially getting larger. More or less without any fancy waffling about."
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6x0knm | What keeps me from rolling off my bed at night? | If I sleep alone in a Queen size bed, for example, I could theoretically fall asleep on one side of the bed and wake up on the other side. But what keeps me from rolling off entirely? | Repost | explainlikeimfive | {
"a_id": [
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"Ever seen people falling asleep sitting upright, and then slowly slouching over until they realize it and snap to enough to sit upright again, and then fall immediately back asleep? Same thing: your body's sense of acceleration doesn't stop when you go to sleep. Your body knows and wakes up when it suddenly accelerates (like if it's about to fall off a bed). You probably stop yourself from rolling off a bed more often than you know, because most of the time you go right back to sleep and forget the whole thing.",
"You never go completely to sleep at night. A small part of your brain never sleeps and always watch out for dangers. It is this part of your brain that will listen to your alarm and make you wake up. It is also making sure you do not fall off the edge of the bed.",
"The brain also shuts down some motor functions to keep you from acting out all your dreams, of course this doesn't always happen (e.g., sleepwalking) and sometimes you wake up while the body is in this state which is known as sleep paralysis.",
"This is actually due to evolutionary traits we picked up, they were to keep us from falling off of branches while we were asleep if you were to start leaning too far in one direction your body's reflexes would kick in to catch you and because reflexes are actually \"shortcuts\" in your neurological system your brain doesn't need to \"wake up\" to keep yourself balanced."
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6x60s9 | Why do games and cartoons have that obviously not-fitting/hit here/interact part of a scenario, that doesn't blend to the rest of it? | Repost | explainlikeimfive | {
"a_id": [
"dmdc15q"
],
"text": [
"Do you mean the color, like when in old cartoons you could tell which drawer the character was going to open because the color was slightly different on that one drawer? If so, that's because the animation is done in physical layers and to save labor the unchanging background is a single picture and the changing foreground (in this case the one drawer and the character who opens it) are different physical drawings drawn and painted by different people, so the colors do not quite match. If this isn't what you were talking about then I apologize for not understanding the question."
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6x8qad | Why does staring at the sun make me sneeze? | Repost | explainlikeimfive | {
"a_id": [
"dme180f"
],
"text": [
"Because you have a photic sneeze reflex, which about 20-30% of people have. The mechanism of action is not well understood. It's possible that wires get crossed in your brain, and that the stimulus of bright light makes your brain think there's something in your nose."
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6xd1ei | Why do humans have physical and mental limiters. | Repost | explainlikeimfive | {
"a_id": [
"dmezmhy",
"dmez815"
],
"text": [
"This 10% of our brain bullshit is, well, bullshit. It's a misconception from the fact that we only use 10% of our brain at any given time (that's also only partially true). The way neural networks are is that you simply can't use all the pathways for a calculation. It's like saying you'll get to work faster if you use all the roads rather than the fastest single route.",
"These are both false. We'd be vegetables if we could only use 10% of our brains. Not sure where that 30% thing came from, but we don't usually need 100% of our strength to perform daily tasks. We save 100% of our strength for times when we need to lift a car off of someone who's been in an accident, for example. Adrenaline aids in those endeavors."
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6xftpf | if the Chinese language uses characters instead of an alphabet, and there are over 100,000 Chinese characters, how do they type up things on the internet? | Repost | explainlikeimfive | {
"a_id": [
"dmfjzvp",
"dmfmhh4",
"dmfmpvj"
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"text": [
"Most Chinese computer users type on a normal QWERTY keyboard. They type in Pinyin, which is a way to convert Chinese characters into letters. Then the computer converts it into the Chinese characters.",
"Chinese type Pingyin, which is the sound/pronunciation of each character. Therefore, typing Chinese is just typing the sounds you make.",
"While typing phonetically, the system automatically pops up conversion options and converts them to the actual characters you mean. It works very similar to predictive typing/autocomplete on modern English cell phones, and is just as fast and easy. Most Eastern languages have phonetic alphabets that are much smaller than the full language character set. Ex: Japanese can be represented easily in English characters, or using the 46 character kana set. Both of which easily fit on a standard keyboard."
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6xi5ah | How does GPS work? | Repost | explainlikeimfive | {
"a_id": [
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"dmg6d7a"
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"text": [
"Hard to know how simple to make the explanation, but here goes. Imagine you don't directly know where you are but, somehow, you know the distances from you to New York, from you to Seattle and from you to Miami. You could get out a map and figure out where you must be. The GPS system has a bunch of satellites in orbit around the earth. Each one transmits a signal that says where it is. The signal takes a certain very short time (called the time of flight) to reach the earth's surface and that time tells you how far away the satellite is. The satellites send lots of other stuff, but the main information is location and the receiver calculates distances. Your GPS receiver picks up those signals and thinks to itself \"Hmmm ... there's a satellite that is a known distance away, and there's one that is another distance and there's another. Each satellite is telling me where it is and I know how far away it is, so I can calculate where *I* must be\". Strictly speaking, the calculation is based on the differences between the times of flight, but that is harder to visualise.",
"GPS is a surprisingly simple series of time/distance 'math problem' in a lot of ways It uses the concept of trilateration Imagine this: you are trying to figure out where you are exactly in your neighborhood. You know you are exactly 1001 meters from your town center's statue. So you draw a circle exactly 1001 meters around that statue, and now you know you are somewhere on that circle. Now say you also know you are exactly 500 meters from the biggest tree in the nearby park. You draw a 500m circle around it and you find out that circle intersects the 1001 meter circle in a couple of points. Now you have narrowed yourself down to a couple possible points, but you still aren't sure. Now let's say you know you are 750 meters from another landmark: this third circle is drawn, and now you find where all 3 circles intersect. Now you know where you are. That's the basic concept behind GPS: satellites in space broadcast a signal. That signal is received by your GPS receiver and decoded. It then tries to find out where you are. But you have to solve a new problem: How far are you from that satellite? But that opens up new problems. Since satellites move, where was that satellite? How does your receiver know? Basically, these satellites broadcast who they are (which satellite is sending the signal) and time data. To calculate how far you are from the satellite, you take a known constant - the speed of light - and multiply it by the time difference between your receiver and the time data the satellite is sending. That gets you a distance. But wait - how do you know where the satellite was that sent that signal? What if your own receiver's time is wrong? Your calculation on distance would be way off! So your GPS receiver has an 'almanac' that lists the status and when and where a satellite will be, as their orbits are managed from the ground. Using this data, you can now pick up a signal from say, satellite 34, and know approximately where its position is in space. You aren't sure where you are, but you can take its signals and start calculating some possible solutions. These GPS signals also contain a timestamp close to when it was broadcast, so your receiver goes \"oh, I'm on the wrong day, let me fix that\" and takes the GPS date and time and says \"hmm, well I'm probably pretty close to the time I'm receiving\" By doing that, it is \"aligning\" itself to the satellites, and as it receives signals from multiple satellites, starts refining its data to get an accurate GPS time from which it can use its almanac and the satellite's own position data that is broadcast and figure out which GPS satellites are where, and thus get an accurate distance to each satellite and thus find an accurate location. The other neat thing is that GPS satellites broadcast almanac data too, to update receivers as GPS satellites aren't static objects and need to be maintained or reposition or what not. Thus, the next time you turn on GPS in your car or on your phone, you'll see it take some time to start up and get your location accurately. And that's because it's doing all those math calculations in its processor to figure out where it, and thus you, exactly are. PS - fun trivia: GPS was originally designed by the US military to help US Navy ballistic missile submarines get an accurate location on where they were on Earth to launch nuclear tipped missiles at a moment's notice. Think about that next time you use it to tag your location"
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6xjvbo | Benefits and drawbacks of universal healthcare vs privatized? | Repost | explainlikeimfive | {
"a_id": [
"dmgi0pq"
],
"text": [
"Watch Michael Moore's documentary Sicko. It does a great job explaining these things. In essence, most of the \"issues\" with socialized medicine are lies told by people who are paid off by the insurance industry. The quality of care in places with socialized medicine is as good as the US, easily. The only real issue with socialized medicine is that there are sometimes waits on non-critical surgeries, but anyone who wants to get it outside of the system is free to do so at their own expense. Furthermore, if the US were to socialize it's system with the current amount of money we all pay for medical care including insurance, you could probably eliminate the wait time problem entirely with the only limiting factor being the number of doctors. Most of the costs in our current healthcare system are due to corporate desire for profit rather than true expense. And finally, the vast majority of doctors don't go into medicine because of the pay. This is because, A, most of them just want to help people, and B, most are paying off ridiculous amounts of student loan debt and also have to pay a ridiculous amount of money for malpractice insurance. So really it kind of evens out for the doctors in the end, well, except that doctors in socialized countries get to help more people"
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6xkyas | Why is it when you need to take a dump really bad, that the closer you get to the toilet the harder it gets to hold it in? | Repost | explainlikeimfive | {
"a_id": [
"dmgo915"
],
"text": [
"Someone will definitely post a better answer. But here's this for now.... I think* it's a similar situation to why it's recommended you only use your bed for sleeping. Your brain passively identifies your bed as a spot for sleeping, which makes falling asleep easier. Or even just thinking of your bed may make you sleepy. Likewise, because you regularly use the toilet for pooping/peeing. Your brain passively knows you're on your way there and may begin some of the bodily responses to prepare for the poop.."
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6xm4c6 | Please educate me on how data is stored inside metal and how computers work | Repost | explainlikeimfive | {
"a_id": [
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"text": [
"Imagine a hard drive as a piece of squared paper. Each square represents a bit. The data is written in the squares in binary code (with 0s and 1s). If the square is filled, it's 1. If it's striped, it's 0. If it's empty, it's available space. Now, the actual hard drive has a platter with tiny magnetized regions. Each region represents a bit. If a region is magnetized in North polarity, it's 1. If it's South, it's 0. That data is transferred to and processed by central processor. It \"understands\" binary code and EXEcutes commands to process the data and/or send the results to output devices (display, speakers, printer, etc)."
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6xnct7 | Why do we have Daylight Saving Time, and why does Arizona ignore it? | Repost | explainlikeimfive | {
"a_id": [
"dmh47fp",
"dmh9fq1",
"dmhevy5"
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"text": [
"This is a good article and has some good links with studies. From the article: \"According to an Arizona Republic editorial from 1969, the reason was the state's extreme heat. If Arizona were to observe Daylight Saving Time, the sun would stay out until 9 p.m. in the summer (instead of 8 p.m., like it does currently).\" URL_0",
"It saves on energy because people spend more of their awake hours in daylight. So that's one less hour of electricity used for lighting. During times when energy conservation was particularly important--World War II and during the 1970s energy crises, for example--the US went on daylight savings time all year round. There was a measurable effect on energy usage during those times. So sure, no, nobody gains or loses anything, the earth continues to rotate irrespective of what time it is. But that's not the point of the change.",
"DST is a way to use better daylight hours, as they change in winter/summer. What this means is that you will have your \"active\" hours inside daylight hours instead of having some active hours at night, having lights on. This is specially necessary in countries far from Ecuador line, were daylight hours change significantly It was thought to save energy, but should be more flexible in my opinion. Edit: I don't know why Arizona ignored it. Do they have 24 hours of bright sun every day?"
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"http://www.abc15.com/news/state/daylight-saving-time-spring-2016-why-arizona-doesnt-observe-daylight-saving"
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6xqqld | - how do people solve Rubick's cubes so insanely fast? | Repost | explainlikeimfive | {
"a_id": [
"dmhsbd3",
"dmhs6t2"
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"text": [
"Rubiks cubes are pretty cool when it comes to how mixed up a cube can actually be. No matter how long you spend altering a cube it will never be more than 20 face turns away from being solved. This means that if you know all the rules to solving them, its just a matter of how fast your hands can move.",
"Algorithms. They memorize and practice them until eventually there is no need to look at a cube while solving, hence the \"inspection\" time they are given at competitions. They look at the cube, find the correct algorithm, and solve it, all in the span of a bout 10 seconds."
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6xtoqo | For over 15 years, every week we hear about breakthrough medical and science discoveries that are going to change the world soon. Like cancer getting cured and all kinds of stuff like that. Why aren't we seeing any of this in practice / commercially available? | Repost | explainlikeimfive | {
"a_id": [
"dmid2jd"
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"text": [
"Because newspapers sensationalize science, often taking one small detail out of context and making it a headline. But thats not how science works. Especially for anything thats used on humans. It can take decades of testing, and any potential issues means something isn't viable for human use and gets scrapped."
],
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6xxmfo | Why can wild animals eat other animals raw but if humans try it we get sick? | Repost | explainlikeimfive | {
"a_id": [
"dmj7tlv",
"dmj8418"
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"text": [
"We don't get sick from the rawness of the meat, we get sick from the microbes and such that can reside is raw meat. Cooking tends to kill that stuff. Animals get sick from raw stuff, too. Have you ever had a dog who ate a rotten mouse? Get ready for some upset stomach action and explosive diarrhea.",
"But we can and do eat raw meat. Sushi, sashimi, poke, beef Wellington, raw venison, etc. I just ate some bomb raw yellowtail the other day. As long as its fresh and free of bacteria and parasites you're good. It's not the meat that makes you sick, its contaminated meat."
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6xxn2y | With everyone having a cell phone and constantly texting, why aren't we able to text 9-1-1 operators? In life threatening situations, you may not be able to actually speak on the phone. | Repost | explainlikeimfive | {
"a_id": [
"dmj7kx5"
],
"text": [
"Yo ho ho! Yer not alone in askin', and kind strangers have explained that it's being implemented now: 1. [Can you text 911? ]( URL_2 ) 1. [Does texting 911 work the same way as calling? ]( URL_1 ) 1. [ELI5: Who doesn't 911 Services not have a way to contact them through text? ]( URL_0 ) 1. [ELI5 Why isn't texting 911 a thing yet? Are there technological issues stopping it from happening? ]( URL_5 ) 1. [Can you text 911? ]( URL_4 ) 1. [ELI5: What's the hold up with the ability for residents to text 911 for emergencies? Is it a technology-related problem? Jurisdictional? ]( URL_3 )"
],
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"https://www.reddit.com/r/explainlikeimfive/comments/5x0cf5/eli5_who_doesnt_911_services_not_have_a_way_to/",
"https://www.reddit.com/r/NoStupidQuestions/comments/6m65ze/does_texting_911_work_the_same_way_as_calling/",
"https://www.reddit.com/r/NoStupidQuestions/comments/648dmn/can_you_text_911/",
"https://www.reddit.com/r/explainlikeimfive/comments/5oya18/eli5_whats_the_hold_up_with_the_ability_for/",
"https://www.reddit.com/r/NoStupidQuestions/comments/2nc5ti/can_you_text_911/",
"https://www.reddit.com/r/explainlikeimfive/comments/3ok1p6/eli5_why_isnt_texting_911_a_thing_yet_are_there/"
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6y0s4o | Why do wind turbines have 3 blades? | Repost | explainlikeimfive | {
"a_id": [
"dmjtmvf"
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"text": [
"This is because when one blade is in the horizontal position, its resistance to the yaw force is counter-balanced by the two other blades. So, a three-bladed turbine represents the best combination of high rotational speed and minimum stress. Mind you the early models all had two blades and some remaining one or two megawatt sized turbines still have just two blades. This was due to the technology and materials at hand at the time. 30 years ago, two government standard blades weighed 50 tonnes. Today, 3 regulations blades weigh 51 tonnes. Some pretty good advancement has been made in the field."
],
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6y14u0 | Why are most cop cars the same model? I know they switch the engines but what's so desirable about the car model itself? | Repost | explainlikeimfive | {
"a_id": [
"dmjwb35",
"dmjw94c"
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"text": [
"They're \"fleet vehicles\". All built on a fairly bare chassis with not a lot of options and sold at a volume discount. And having the same make and model of vehicles means you don't have to keep various versions spares for a bunch of different accessories like light bars or laptop mounts.",
"Car manufacturers make specific models of cars that are intended to be used as cop cars and market them to police forces across the country. These cars tend to have upgraded engines and suspensions. They come pre-installed with things like push bars on the front, searchlights and screens to separate the front from the back. There are only a few models of these cars around. For a long time the most popular model was the Ford Police Interceptor which was an upgraded Crown Victoria. That model is no longer being produced and newer police cars are a little more diverse."
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6y5tte | Why do car companies have different names for cars in various regions? Like the the Toyota 86 is called that in NA, where it's called the GT86 in Europe? | Repost | explainlikeimfive | {
"a_id": [
"dmkyd38",
"dmkyxal"
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"text": [
"Usually because some words don't work well in some markets. Examples: * Honda Fitta became Honda Jazz in Sweden, because \"fitta\" is the Swedish equivalent of \"cunt\". * Mitsubishi Pajero has a different name in some countries, because in Spanish (or maybe it was Italian, don't remember), Pajero means \"fag\". Sometimes, it's because a car is re-branded. Say, for example, that Chevrolet needs a small car for the US market. They don't have such a car in their lineup, don't have time to develop one, and they aren't good at small cars anyway. So, they buy cars from another manufacturer, and put their own name on them. So, for example, Suzuki Ignis is marketed by GM as Chevrolet Cruze. People who wats to buy American buy a Chevrolet and think they get an American car.",
"Sometimes the name directly affects sales. When Ford released the Pinto in Brazil, nobody bought it. This is because the word \"pinto\" (pronounced peen-cho) in Portuguese means \"tiny dick.\" They renamed it to Corcel."
],
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6y6a05 | What does it mean when a company throttles data, what is throttling? | Repost | explainlikeimfive | {
"a_id": [
"dml0d6u",
"dmkzb95"
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"text": [
"It's slowing down the transfer of data, such as downloads, websites, etc. Sometimes everything you access, sometimes just something specific like bittorrent. For instance, suppose you're on a phone plan. The reddit frontpage right now is 1.8MB. This is 1.8 * 8 = 14.4 Mbit. If you have a 10 Mbps connection, this will take 1.4 seconds to download. That is, if you go to URL_0 , it will take 1.4 seconds to transfer all the data needed to display the page. Now suppose you have a 10GB limit per month, and after you reach it you're throttled to 64 Kbps. Now the frontpage takes almost 4 minutes to download.",
"Depending on what your doing or how much data you have used a service provider will drop your bandwidth to a significantly slower speed. So the big open internet problem is that if you wanted to watch Netflix but if the internet wasn't open an ISP could essentially severely limit your speed to Netflix, either because you didn't pay for high speed access to Netflix or because Netflix didn't pay for a fast lane to customers for that ISP. Or say for instance you have an unlimited cell phone data plan but you're using like 32 gb of data a month, they could drop your data speed because you're basically hogging a lot of bandwidth all the time."
],
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6y9qol | The Doomsday Clock. What is it's purpose if it's always at around 5-to-twelve since before the Cuban Missile Crisis? Does it actually serve a purpose or reflect any real measurement or is it just a whistle-word for headlines? | Repost | explainlikeimfive | {
"a_id": [
"dmlnxmi",
"dmlo4nr"
],
"text": [
"It's not meant to represent time in a literal sense. It is meant to represent how close the world is to a man-made global catastrophic event happening. Time is simply used as an analogy for social/political/other factors, as in \"less time left\" = \"greater danger.\" Close to midnight is thus \"Close to a dangerous event happening/lots of risk\"",
"As Dr. Manhattan said. And I'm somewhat paraphrasing. I would argue that a symbolic doomsday clock is as nourishing to an intellectual, in the same way as a picture of oxygen is to a drowning man."
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6yaisw | Why if I were to shut a box made of mirrors in a light room, and then open it again in a dark room will no light come from the box? | There must be a good reason that I just can't think of, but shouldn't in theory the light just keep bouncing from mirror to mirror until the box is opened? | Repost | explainlikeimfive | {
"a_id": [
"dmlu60j",
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"text": [
"Mirrors don't perfectly reflect all light, they absorb a small percentage of it. If each bounce absorbs 0.1% of the light, then after 10,000 bounces, basically none of the light is left (0.0004%). In a small box, 10,000 bounces of light will happen in a microsecond or less!",
"In theory, light will come out in a blink. In practice, this will not happen because there is always loss in mirrors.",
"Mirrors don't reflect perfectly. It absorbs a tiny amount of the light every time it bounces. You can see this with mirrors facing each other - the reflection will turn slightly green after several bounces. Light travels at the speed of light so it completes about 10 billion bounces before you can even blink your eye. The light will be completely absorbed the second you close the box."
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6ybhsb | Why do computers still ask us to “Safely Eject External Storage Device”? Does ejecting unsafely really risk damage to files or the device? | Repost | explainlikeimfive | {
"a_id": [
"dmm360l",
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"text": [
"Yes, it's still necessary. If you copy a file onto an external hard drive or flash drive, the program you're using (let's say windows explorer) will display a copy dialog and progress bar showing the copying process, and then show that it has completed. However, windows explorer is not directly copying the file itself, rather it's communicating with the operating system, Windows in this case, which is handling the nitty-gritty of the copying. While Windows might report to explorer that the copying is finished, Windows itself may not be done actually writing the new file behind the scenes. It's essentially just telling explorer \"I don't need anything more from you, I can handle it from here\". If you pull the drive out at this point, you may end up with a corrupted or incomplete file, or the entire file system could become corrupted. By safely ejecting it, the operating system ensures that everything is completed before the device is removed.",
"In the good old days, if you pulled external media without going through some unmounting procedure first there was a chance the files would still be in cache to be written to the media as opposed to actually written. So a file might end up corrupted, or the disk may need formatting, depending on where the write was. Un-mounting or ejecting the media would flush any write cache and make sure everything was set on the disk."
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6yey3e | How do they know that nothing can go faster than the speed of light? | Repost | explainlikeimfive | {
"a_id": [
"dmmubcn"
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"text": [
"I'd suggest you read this [excellent post]( URL_0 ) by u/Astrokiwi over at r/askscience, who gave a really good answer to this question"
],
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5
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6yeysj | Why are courtroom sketch artists still a thing? While I understand not wanting live broadcasts, why are courts still in the dark ages insofar as refusing to allow still photos for historical purposes? | Repost | explainlikeimfive | {
"a_id": [
"dmmtnuj"
],
"text": [
"I'm assuming here that you're talking about countries outside the USA, where courtroom photos are legal. In the UK, courtroom photography and filming are not permitted because live shots of suspects and trials could result in fallacious information being released to the \"outside world\", potentially resulting in courts being defamed and in the worst case resulting in a mistrial. *edit* it is also due to the likelihood that suspects will be less willing to admit guilt or submit verbal evidence if cameras are in the courtroom."
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6yg0v8 | why can't there be cars that look as cool as lambos, but with cheap components to make them as cheap as a regular Honda | Repost | explainlikeimfive | {
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"A lot of comments are missing another factor: Car companies don't *want* their cheap cars to cannibalize sales of their high-end sports cars. Let's suppose for a moment that they are in fact able to make a Dodge Dart look like a convincing Ferrari without increasing the cost. Further, let's suppose that people wouldn't heap disdain on the fancy-looking Dart for being a shitty car posing as a nice one. Both of those things are probably iffy prospects, but not outside the realm of possibility. That would be a great thing for Dodge, right? Except, Fiat owns both Dodge and Ferrari. So what they've actually done here is to replace some of the sales of a $2-400,000 car which probably earns them $50,000 or more in profit, with a $17,000 car that earns them probably closer to ~~$1500~~ $200 profit. These companies aren't *supposed* to compete with each other. Edit: As several have mentioned, I was probably overestimating the profit margins on the low end. Honestly the correction only makes this logic more compelling.",
"There's a multitude of reasons. I'll cover what I think are the major ones: 1) Supercars are impractical 1a. Most tend to be 2-seaters with not much room for cargo. People who drive supercars don't care about practicality as much as us 9-5ers because generally the supercar isn't their primary mode of transportation (or they have other ways to get around the limitation such as having other people to deal with moving their luggage from one place to another or just buying everything new at their destination) 1b. Supercars are low With a lot of them, even going over a normal speedbump in a parking lot is a challenge. 1c. Supercars have intricate, delicate bodywork Tap your Honda's bumper into a wall or hit a tall curb with it and it's probably no big deal. It's made to take a bit of abuse. In a supercar that would be some cracked carbon fiber or fiberglass 2) Supercars are kinda big 2a. Supercars are generally somewhat long with a wide wheelbase On an economy car with a smaller engine that would hurt acceleration and gas mileage. Plus it'd be a pain to park (This could almost go under impracticality) 2b. Supercars have big engines Economy cars have small engines in general, because if you can't afford an expensive car you probably can't afford a ton of gas either. Supercars have no such constraints, so they tend to be bigger with a wider wheelbase and make up for the weight with more power (They also mitigate their weight from their large size by using expensive lightweight components) Put all that together and you get a situation where nothing in the economy market *quite* looks like a supercar. A lot of things have some elements of supercars though: The 1st generation Toyota MR2 ( URL_0 ) had 2 seats, not much room for cargo and lots of sharp angles. But it had a relatively sane ride height and bumpers that wouldn't crack at the slightest provocation. The current generation Honda Civic Si ( URL_1 ) has all sorts of crazy angles and vents on it that are typically reserved for much more expensive cars, but the format is a 2-door 4-seater with a decent trunk. That makes the overall shape look a lot more \"normal\" There's lots of other stuff to mention such as engine placement and the effect that has on the overall shape of the car (and how that contributes to the impracticality). Going to quit here before I write a novel, though.",
"There kind of are (see: [kit cars]( URL_0 )), but the problem is that nobody really wants them enough for it to be a viable large-scale market.",
"There are, sort of, they're called kit cars. Kit cars are often laughed at in the car world because it's like wearing a fake Rolex and often times they're lacking quality. The companies that make them don't have/can't afford to use things like carbon fiber and even the really nice ones only look legitimate from about 50 feet away. Most super cars are made of very expensive alloys and carbon fiber. The attention to detail as well as the materials are what really makes them so expensive. The only exception I can think of is the Shelby cobra kit cars, but they're still expensive. You get what you pay for.",
"A perfect example here is the new [Corvette]( URL_1 ) It is often compared to the [Ferrari 488]( URL_0 ;) I'm sure you can see why. The new Corvette is a quite capable sports car, and could actually run with Ferrari's on a track (although it would probably lose). The Corvette costs $55,000, while the Ferrari costs $250,000. Why? One aspect is the interior. I've driven a Corvette: The inside is all cheap plastic and Best Buy-esque navigation systems. Beyond that, there are tons of small details Ferrari paid attention to that Chevy didn't: Weight, balance, fitment, quality of parts, etc. So, you can get a car that is (most of) a Ferrari for 1/5 the cost. The remaining ~$200,000 goes into that final 10% that makes a Ferrari one-of-a-kind.",
"There are plenty. It's just people go by price in rating them cool. a Honda S2000 is every bit as sleek as a Jaguar, but since it's way cheaper, people see it as cheaper.",
"Part of what makes them look cool is that they're expensive and you can't get around that. You can definitely tell the difference between a $100 suit, and a $1000 suit, right? even if the $100 suit tries its hardest to emulate the $1000 suit. Sometimes quality can't be matched without $. So Honda may try to emulate Lamborghini's paint lets say, but it won't look exactly the same or else it'll drive the price up. Lamborghini doors for example. Regular cars are hinges while the vertical door needs a hydraulic or else it won't stay up. Those are more expensive than regular hinges. So even if they wanted to, they couldn't make it so it's as cheap as a regular Honda. Also must think of technology. Exotic vehicles can put cutting edge tech in their cars because they'll throw the $2500 piece of tech into the price because $ isn't an option for ppl buying lamborghinis. Honda will wait until the tech is cheap enough to include it where it won't hike the price of the vehicle up.",
"A lot of the things that make Lamborghinis look cool also make them impractical. They are small and low with the engine behind the driver and with no back seat. Their sloping roof lines limit headroom. They have laughably small trunks. They are difficult to see out of. If you want to build a cheap car that will sell you need to make it higher off the ground so people can easily get in and out of it, so they can have a good view of the road and so they feel like they are high enough up to be safe. You need to make the passenger compartment taller - there needs to be a lot of headroom and useful storage space. You want to put the engine in the front because it's cheaper to manufacture and because it leaves the back open for a large back seat and a large trunk that can be made larger by folding down the rear seats. You can buy relatively inexpensive cars that look cool. Mustangs are designed to look cool and they aren't all that expensive. But, just like Lamborghinis, they sacrifice practicality in favor of looks, so most people buy practical sedans or SUVs instead.",
"I've felt like this about old muscle cars for a long time now. Why can't I just have a 2010 corolla that looks like a 69 nova?"
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"http://car-configurator.ferrari.com/titan/TitanServicev1.aspx?RenderScript=f142m&width=1500&height=800&base64off=&workingWidth=1500&workingHeight=800&option=*EXT/065427400,*EXT,ECN,CER,BRA,WHR,WHB,EC,WH,*INT/364018500,*INT,CMM,SEA,CSB1/364700800,CSB1,SS3,SSS,SSB,*CAR/364900152,*CAR,CP1,CPC,REV,IOR,CM,SS,CP,IO,STDStitching,STDRoof,STDDSH7,VRDashInserts,STDSteering,VRSWInserts,STDDash&format=jpeg&quality=95&assetPath=EXT_TURN/000&replace=frame:00&",
"http://st.motortrend.com/uploads/sites/10/2015/09/2015-Chevrolet-Corvette-Stingray-front-drivers-above-view.jpg"
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6yj0lm | Why do shallow injuries (e. g. paper cuts) often seem to hurt more than deeper ones? | Repost | explainlikeimfive | {
"a_id": [
"dmnr55g"
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"text": [
"The vast majority of nerve endings are at the surface of skin. Deeper into your skin, you're not as sensitive to pain. Also, deeper in your blood will clot and provide a protective layer for the nerves there, while at the surface paper cuts typically don't cause much blood."
],
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6ymf8l | Why do we have to drink water? | Repost | explainlikeimfive | {
"a_id": [
"dmognlk"
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"text": [
"We release water through are skin as a cooling mechanism (sweat), many of our cells use water in reactions that are essential for our function and we use water to carry away unwanted stuff (piss), among many other uses of water. All of these mean that if your body isn't supplied with water it struggles to function. Your blood becomes more concentrate with unwanted chemicals as your kidney tries to maintain moisture by not producing urine, as a result your entire cardiovascular system has to work harder to keep blood circulating. Your brain tissue is reduced temporarily, reducing your ability to think and react. For more severe cases simply moving too fast can cause you too faint as your blood is circulating nutrients so poorly."
],
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6ymque | How USA, a 300 years old civilization, became so quickly one of the strongest civilization in the world? | Repost | explainlikeimfive | {
"a_id": [
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"text": [
"USA didn't start from scratch. It was founded on the shoulders of people who had been \"civilised\" for centuries. And if you're asking yourself how quickly after foundation it became such a powerful nation (merely 200 years). That's not a record. Spain holds the record with \"a few months\". 1492 was a good year.",
"There are a host of reasons, but geographic isolation, rich natural resources that allowed self-sufficiency, and political stability seem most important. **1. Geographic Isolation.** The United States is geographically isolated from major potential enemies. It has a northern border with a small friendly nation, and a southern border with a small usually friendly nation. Its major competitors have to cross an ocean if they want to invade, which is incredibly difficult. **2. Natural Resources.** Land for food and growth, minerals, timber, oil, coal, you name it, American has it. Because of the resources the country's economy has always been robust and able to change and expand, while it has not relied on any foreign nation for the entire supply of any needed resources. **3. Stability.** This might be the most important factor. The United States never had an aristocracy, it never had royals fighting for power, never had warring factions constantly on the brink of internal strife. Apart from the Civil War, the political structure has been stable and constant, the legal system has provided for reliable conflict resolution, and the criminal justice system has ensured relative tranquility and safety. A lot of countries have not had this, or have not had it with such consistency."
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6yn6tl | Why can't we be our own ISP? | Repost | explainlikeimfive | {
"a_id": [
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"> What's keeping us from just getting the internet to us directly from wherever it comes from? Because there isn't a connection to your house directly from the Internet backbones. > What does an ISP do? They connect you to the internet. They own the physical lines that go to your house that you can connect to the internet from. If you end your service with them, you can't use their equipment or infrastructure. EDIT: As an analogy. Think of roads and re-ask the question: \"What's keeping us from just getting on the Interstate to us directly from our house? What do local roads do?\" The answer is: you can just build your own private road directly to the Interstate, but there are lots of issues preventing this: you probably don't have the resource to make your own roads; you don't own all the land between you and the Interstate; you would still need permission to connect to the Interstate.",
"You can certainly be your own ISP. All you need to do is lease a fibre from a phone company, or get city permission to dig a trench and lay your own fibre from your house to a peering point nearby. Then you need a carrier class boundary gateway router, about $125,000, to connect to all your peers without slowing them down. You're set, no more pesky fees, no spying on you, no filtering. Alas, you also have no money.",
"The internet doesn't come from any one place. It's simply a bunch of different networks all hooked together, hence the name (Inter-network). What your ISP does is provide connections to other networks. They negotiate agreements with other network providers who are, in turn, connected to yet more networks. Through this system of interconnected networks you are able to talk to any device connected to the internet. There's technically nothing stopping you from running your own ISP but it would be technically and economically difficult. You would need to negotiate at least one connection to a major network provider to allow you to send and receive data to and from the larger internet. Most large network providers aren't going to waste time with an individual home user. They would rather sell very large connections to an ISP and then let the ISP handle the work of dealing with individual customers.",
"The Internet is a worldwide network of networks. You can't access the Internet without ISPs being involved because ISPs *are* the Internet. They are the organisations that connect private networks like your home network or corporate networks to each other. If you wanted to be your own ISP you'd have to make a deal with a higher tier provider (essentially an ISP that connects multiple ISP networks together) to allow your network to connect to their's.",
"An ISP has a connection to really high speed Internet, the kind that links with fiber optics. Yes some ISP's have fiber optics to the door. It is too expensive to be a standard solution. So buy routers and ways to connect. Fancy routers not available in your store. Then get someone competent to connect you. The closes thing I know to this is a system set up on an island in the state of Washington. Residents on the island wanted high speed Internet which no local ISP was willing to provide. These were well to do technically savvy residents. They established a microwave link to the mainland and put in a system of routers on the island. They charged dues to pay for the system and a local retired resident took care of local maintenance."
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6yv0bo | How do computers convert binary into instructions? | Repost | explainlikeimfive | {
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"This is the task of the CPUs control logic. All these transistors that make registers, busses, adders and the other fuctions of the CPU is controlled by single bit control signals. So you may have hundreds of these signals in a core. The control logic is a block that converts the instructions you feed the processor into these control signals. There is also a counter per instruction so that one instruction can take multiple cycles. The control logic can be made in different ways. The simplest way to think of it is as a read only memory which takes the instruction in as address input and outputs the data at that memory location as the control signals. However this is inefficient so they usually have ways to reduce the space requirements of this logic and end up with an FPGA or something similar. If you want to know more I recommend a youtube series by Ben Eater where he builds a very simple CPU using simple logic components."
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6yw82b | How does Google Maps know about traffic in specific locations? | Repost | explainlikeimfive | {
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"It is fairly accurate. Your phone knows where you are (thanks to GPS) and can extrapolate how fast you are moving between GPS pings (if you travel about 5,000 feet in a minute, you are going about 60 mph). Since there are a great number of phones all transmitting this information back to Google, Google has a good sense of what the traffic is on major roads at any given point in time.",
"Google integrates traffic data from multiple sources. For some regions they get data directly from the Department of Transportation. Google also combines this with real time information from people using their smartphones with location tracking turned on."
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6yzcvc | Why do birds bob their heads as they walk? | Repost | explainlikeimfive | {
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"It's a stabilization method for their eyesight. Since many birds are prey to other animals, they have to be constantly on the lookout. Bouncing their heads up and down when they walk like we do would make it very hard for them to pay attention to anything, especially since they can't lock focus like we can. So instead, they keep their head still as their body moves forward then very quickly bob their head into the next position. So overall, the cumulative time moving their head, and therefore not on the lookout for predators, is reduced to one quick bob rather than a bunch of up and down movements."
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6z0rll | How is open source software more secure? | Since I can see the whole code, if, say, I find a vulnerability, cant I just exploit it? | Repost | explainlikeimfive | {
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"You could certainly exploit that vulnerability, but because everybody can also see the code, there's a good chance someone else has also noticed that vulnerability before you, and steps to correct it might already be in progress. Additionally, with open source code, it is often far easier to get in touch with the developers and report issues directly to them than it is with closed-source projects. As a result, security issues can sometimes be resolved faster. With most open-source code, the public is often allowed and encouraged to submit code improvements directly to the developers. So someone could submit the code to fix a vulnerability as a part of them reporting an issue"
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6z2c0t | How come almost everyone (human) in the world has diffrent faces, yet almost all (Let's say deer) look alike? | Repost | explainlikeimfive | {
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"Humans are exceptionally cooperative creatures and that seems to be assisted by facial communication. We have recognition systems finely tuned for human facial expressions so we are very sensitive to them compared to other creatures. We also have much more expressive and varied faces because that is an important way that we communicate. Other animals don't cooperate in this way and it follows that they don't need their faces to communicate information to each other, so they are less expressive and varied. So it is two-fold. Animals haven't evolved to look as different as humans and our brains aren't attuned to the differences in animal faces like we are to differences in human faces.",
"This has to do with how we are good at recognising each other's faces because we routinely interact with other humans for comfort and survival. If we interacted with deer as regularly, and if our survival counted on it, we would be able to recognize specific markings and differences in deer. So the deer really just all look alike *to us*"
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6z4fwp | why do people get the munchies when they smoke weed? | Repost | explainlikeimfive | {
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"Hunger is a side effect of the drug, my man. THC binds to two receptors in the human body, creatively named cannabinoid receptors 1 and 2 (CB1 and CB2 for short). CB1 is located in several places throughout your body, including your brain and your GI system. When THC interacts with CB1 in your brain, it has psychotropic effects including euphoria (it gets you high). In the GI tract, CB1 normally helps to regulate food intake, so when THC meets the receptor there, it causes you to feel hungry.",
"The simplest explanation I had always heard was that THC increases sensitivity of your senses. It doesn't necessarily \"heighten\" them, it just makes you perceive them more. For example, your hearing doesn't actually improve, but the things you do hear feel louder. So things that usually taste good, now taste amazing, and it makes you crave more tastes. This paired with the fact that THC also inhibits the stomach from sending the \"I'm full\" signal to the brain means you never really feel satisfied from eating while high, and can eat until you burst."
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6z6dba | Why does turning it off and back on solve the problem in a lot of cases? | Repost | explainlikeimfive | {
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"What I tend to explain is that when your device or computer goes through a shut down sequence it is similar to you going to sleep at night or leaving your house before a vacation. The devices operational steps of shutting down include turning off services such as location, wifi, Bluetooth, cellular data as well as ending process' for other systems (RAM in particular in computers and smart phones,) which otherwise would be akin to leaving your car on and running overnight. When the device or computer turns back on most machines or devices go through a power on systems test which makes sure all components are on or able to be turned on as it powers up. This process will also turn or kick previously not functioning services back into a working condition."
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6z7vdc | Why does rubbing your eyes when they're closed make you see a bunch of different coloured lights? | Repost | explainlikeimfive | {
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"The phenomenon is known as 'Phosphene'. It happens because your retina can be stimulated by physical pressure as well as my actual light. I'm not quite sure why this is the case but I hope this helps."
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6z8sw6 | Why do you crave more cigarettes whilst drinking alcohol? | Repost | explainlikeimfive | {
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"They're the same cravings, you just have fewer defenses against them. Alcohol impairs executive functioning, the \"grownup\" voice in your brain. At this very moment, your pleasure sensors would like nothing more than for you to do all kinds of stupid shit that would bring on a hit of dopamine. Assuming you're sober, your executive functions modulate and suppress those urges. After a few drinks, not so much.",
"They interact strangely. Both normally get your brain to release dopamine (the reward chemical). However smoking actually suppresses dopamine when you are drunk,causing you to drink more and smoke more in an attempt to compensate. Edit: here's a study on this, it focusses mainly on the increased drinking, but also answers your question re-cigarettes: URL_0 Also, as others have pointed out your normal cravings are harder to resist and there is an element of state-dependent behaviour, where you have previously associated the two activities."
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6z9jq8 | Why does coming back from somewhere always seem shorter than the trip there? | Repost | explainlikeimfive | {
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"I heard an explanation for this a while ago, I'll try to do it justice but I don't know all the scientific terms behind it So when you're going somewhere brand new your brain is taking in all the details, and forming your picture of the area. It seems longer because your brain is working harder to perceive everything about it. On the way back through it you already have those details, so your brain is recalling them as opposed to forming the memories, which uses less power, and feels like it takes less time"
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6zehiy | Why does gravity affect time? | Repost | explainlikeimfive | {
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"In presence of gravity the space dimension is stretched. Similar is the case with time (because they are directly correlated even though they are still their own individual dimensions), time also gets stretched (more accurately, curved) in presence of gravity. In other words, time runs slower in presence of gravity. The more gravity you have, the slower time passes. (Also like others have stated, like many things in science we know the how, but we don't know the why. We don't even know *what gravity is*, so let that sink in. I mean gravity is effect mass has on space time, but I'm not an astrophysicist so I'm not sure if there's more to it than that.) Now here's a bit more in depth example that a 5 year old may be able to understand: Time as anything different than dimensional is a kind of illusion, as it is relative to where the observer is in the universe in respect to objects with mass. If I'm on earth, I'm perceiving time as being normal. If there is a second earth somewhere far away with let's say, a black hole close to it, the person on that earth will perceive time just the same as the person on earth one perceives it. But in actuality, earth number two has that large gravitational mass of a black hole close enough to it that the gravity of the black hole is affecting earth two by the bending of space time that happens with large amounts of mass that results in gravity. Since space and time are one and the same, the bending of this space via gravity is also bending time. The more bent spacetime is, the slower time goes relative to the observer. So earth two is going way slower in time relative to the viewer on earth one. Two hours could go by on earth two which could amount to ten years on earth one. Neither earth will feel a difference as each observer feels time going at a constant speed, but if each observer visits each other's planets, they will see how much time has differentiated from the beginning of the test. This doesn't mean that if we find a planet where time moves slower that we can live longer, as humans there will still have their normal age limit, it just means that relative to the other earth that has different levels of gravity acting on it time dilates drastically from each observers relative point in the universe. Also, for your second part, it is impossible to know what existed before the Big Bang, and so scientists leave it at that. Most scientists go with the fact that time and space started at the Big Bang and there was nothing before that, because there is simply no way of knowing what was before. (Unless we get into theoretical physics of there being multiple universes that this one stemmed out of, but that's all purely philosophical at this point.)",
"that's the core of Einsteins work and the reason he is so important. Space/Matter and time are linked. as to the \"why\", no one can answer that, all physics can answer you there is \"how\". Why our universe is the way it is and not another way is a question for philosophy or religion. I highly recommend using the search function, as this question is asked on average every other week here.",
"The speed of light in a vacuum is a constant no matter what frame of referance you use. This is the reason time slows down when you start going close to the speed of light. Its complicated math but simply if you are going 1/2 the speed of light and shine a torch forward you see that photon shoot off forward at the speed of light, but for somone stationary they too see it travel at the speed of light not speed of light + the 1/2 speed of light your traveling at. Now when light moves through space it is affected by gravity the same as everything else. If you had an infinity flat \"Earth\" and shot a photon horizontally it would fall at 9.81m/s^2 and hit the ground This is where the explination gets tricky as you have to try and visualize space time as dimensional. Which is hard. But if you have seen these images of a flat \"space-time\" grid with a planet plonked on there bending the space-time grid down and distorting it with its gravity. Now a photon travels allong the lines of this grid. Without the planet there it takes 1year to travel 1 light year easy. But when the grid bends the photon as above follows this bent space-time grid. But the distance is longer due to the planets gravity. [This is what im trying to describe]( URL_0 ) An observer in the gravity of the planet the photon will still take 1 year to travel the 1 light year, but to the outside observer due to the curve and the fact light in a vacuum always travels at the same speed, it will take longer. This means light and therefore time must have been slowed by gravity. In reality its not actually curved but thats the issue with trying to visualize time as a dimensional thing its hard to describe without a wall of math! Edit: spelling"
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6zer4v | How do very rich people handle their money? Do they have a bank account just like us? | Repost | explainlikeimfive | {
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"Someone like Bill Gates has a very small percentage of his money in the bank, the vast majority of his wealth exists as shares of Microsoft. If he needs money he can take a loan against them or sell some shares off to come up with cash It's a terrible idea to keep your wealth in a bank due to inflation so almost everyone has it invested so it grows over time. Anyone who got super rich from starting a company will have most of their wealth as ownership of that company",
"Most people that we think of as \"rich\" or \"super-rich\" don't make money in the same way as most people do. Bill Gates is a great example for this. Most of his wealth isn't in cash in the bank, but in investments. In the case of Gates, his ownership stake in Microsoft is worth $12,524,470,050 (based on today's stock price and the holders information from Yahoo Finance). While some people who fall into the same income class as Gates do get a normal salary, they often choose to be paid with stock in the company they work for instead of getting cash deposited in a bank account. So the question is, how do you make money off of investments?. There are a few ways to turn investments into cash as needed: * Sell them on the open market: You could go to the person or firm that oversees your investment portfolio and ask them to sell a certain number of shares or to sell shares to gain a certain amount of money. The problem with this option is that, at the end of the day, you lose the investment. * Dividends: Companies that are profitable will often pay their investors a part of that profit. This payment is called a dividend, and they can be paid annually, semi-annually, quarterly or never depending on the company. You get a certain amount per number of shares owned. While these payments are often small (less than $1 per share), if you have many shares in a company or investment fund it can add up. * Loans: You can borrow against the value of your investments, using them as collateral. You get the cash up front and pay back the loan over time. If you fail to pay back the loan, the person who loaned you the money gets to keep what you put up as collateral. There are other issues that affect the choice of the wealthy to keep their money in assets as opposed to salaries and cash, the biggest being taxes. I'm not sure where you live, but in the United States there are many tax brackets, and not all income is taxed the same way. If you fall into the super-rich category, regular income is taxed at a very high rate. Regular income includes your salary, for example. However, when it comes to income from investments, they are taxed differently. Dividend income is taxed at a lower tax rate than paycheck income at all tax brackets in the US, so you get to keep more of your money than if you were getting a normal paycheck. There's also capital gains income. When you sell a stock on the open market, the difference between what you paid for the stock and what you sell it for is what the government in the US considers \"income\" from the stock sale, which is called a capital gain. Capital gains are also taxed less than paycheck income at all tax levels in the US. Another reason you might not want to keep money in the bank and instead have it in investments is inflation. Inflation is a reduction in the real value of your money over time due to increases in the supply of money. If you keep your money in the bank, you will gain money over time in interest but lose value over time because inflation is usually larger than the interest paid. So, if you leave money in the bank and take it out decades later, you will have more money in the end but what you can get with that money will be diminished. While not part of your original question, this state of affairs begs the question of why give such a tax break to the wealthiest people. In short, it encourages the wealthy to invest their money in stocks and other financial assets rather than hold money in cash. By investing this money in companies, both new and old, they help to provide the financial support companies need to develop new products and services and ultimately provide greater value to all of society.",
"I have my money managed by a wealth management company that invests it and allows me to draw an income which doesn't decrease the value of the pot.",
"I'm worth a couple million but it's all tied up in real estate, so it really doesn't feel much different than being poor except my bills are bigger.",
"The good practices for personal finance applies to anyone no matter how much money they have. Keep enough money to pay the monthly bills in a bank account, have additional funds available in case of emergencies and lastly invest the rest into stock funds and bonds. If you need additional help at certain points you hire a financial adviser. The difference is really how big the numbers they deal with are. It is also easier for a rich person to hire a financial adviser on a fixed rate as the amount of money might warrant this. But that does not mean that they have a dedicated adviser. One financial adviser might handle the financial details of tens of rich people in addition to people who just want his advice in a single matter. So in general it is not as different. Adding an extra zero to a number does not make it very different to handle.",
"In the UK, for example, [Coutts & Co.] ( URL_0 ) is one bank that caters to the wealthy with private banking. Dealing with large amounts of money is an area of its own (wealth management), which Coutts does too, but they also do typical bank things such as offer current (checking) accounts and issue credit cards. There is more \"hand-holding\" e.g. someone from the bank to handle any problems personally. If you have millions in \"wealth management\", the bank isn't going to freak out if you exceed a £10,000 limit on a credit card, they'll just handle it by moving money around on your orders.",
"Traditional wealth is usually tied up in assets, as stated here, but I am particularly curious about how people with nothing but Iiquidity (a lotto winner, for instance) would handle this.",
"They have special accounts for people with high values. They give better interest, you get a private manager and they are insured for more then standard FDIC. Usually if you are wealthy you'll have several accounts for your liquid cash. That way different managers only have access to one chequeing account not your entire liquid fund.",
"If you're interested, read Brooke Harrington's \"Capital Without Borders\", for how the ultra rich handle their finances.",
"I see lots of comments on keeping less cash in bank and start investing, my humble suggestion is to invest only when you understand what you are investing on. It is foolish to invest just because everyone are investing and you don't understand on what it is that your investment will be doing.Small time Wealth mangers mostly just invest in the index funds, Normal guy does not have an entry to elite fund mangers. Reminds me of quote from Seinfeld \" I let my money do the work for me \" , \" your money has missed lot of work days and been sleeping \".",
"In a former job, I had interactions with what is known as a \"family office\". This is a financial advisor/accountant that exists solely to deal with the wealth and investments of a single family. Technically it needs to be a member of the family, but they are able to \"partner\" with someone that is outside of the family (so if you don't have a accountant in the family, you start a business with one so you can open the family office). Additionally, you are required to prove a familial relationship within a certain number of generations (I want to say it was 10 generations must extend back to a common ancestor). Family offices receive certain exemptions - specifically from the advisers act (1940 act) So what does a a family office do? The answer is everything. From the clients I dealt with, it seems like its the perfect solution for folks that have enough money that they don't want to be bothered by anything to do with it. You have all your bills mailed direcdtly to the family office, they have your checkbook and they write all the checks. So you don't pay your cable, electric, etc, its all handled by the family office. If you wanted to buy a new car, they take care of all the financial aspects of it. They will give you all your investment opportunities, provide you with summaries, etc. Its essentially a financial concierge service for wealthy families. In exchange, they take a percentage per month/year as a fee."
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6zf8c9 | Why were the European Colonists not ravaged by American disease unlike the Native Americans who were ravaged by European/African disease? | Repost | explainlikeimfive | {
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"There's a great CGPGrey video on this on YouTube. Its called Americapox or something. I think it largely states that it was due to the americas not having domesticated animals which humans stay in prolonged contact with (in densely populated areas like cities), and that most dangerous diseases spread from animals to humans.",
"As (can't believe I'm going to type this) /u/bunchofcunts noted stronger immune systems is the main factor, but it should be noted that syphilis went from the New World to Europe and infected many millions of Europeans.",
"Along with what has already been said, indigenous peoples of the Americas had much better hygiene than Europeans, even when they had densely populated areas. This helps stop diseases from not only spreading, but forming/evolving in the first place.",
"Cow, pig, horse, sheep, goat, chicken, duck, camel, pigeon. All of these animals had been domesticated in the Old World and most of them were also carriers of disease. Most of the deadly diseases come from animals, a disease does NOT want to kill its host, unless it thinks its host is a totally different animal, in which case, oops. Compared to that plethora of animal diversity in an Old World backyard, they had just the llama in the New World. Yeah, go figure. The Old World children contracted the diseases when they were small and resilient to the high temperature fevers the diseases subjected them to, making them immune from future attacks via immune system memory. When the Old World people came about, they brought the animals with them as well, as well as numerous other articles made out of those animals. We're also talking about a period of time where people in the Old World didn't bathe out of fear of catching some waterborne disease.",
"Another factor is that Europe is connected to Africa and Asia, while America is isolated, so Europeans have been in contact with more diseases than native Americans in the first place.",
"There were some diseases, such as syphilis that spread back to Europe. There were even some colonies that vanished due to disease. But any American disease deadly enough to ravage Europe would kill the sailors long before they made the 3+ month journey back and so the ships would never make it.",
"Essentially, the European's immune system was more tried and tested with a larger assortment of diseases due to the size of the population living within close proximity for so long and the genetic diversity that came with it. There probably was some crossover with the European colonists being naive to some of the American diseases, but the Europeans had dealt with deadlier diseases in the end and had the immune systems to combat it.",
"You guys may remember the Black Death hit Europe in the 1300s and killed 100 million people. Something similar could have occurred in North America. Also Vikings in Canada and USA c.1000 and no deaths.The reason why the pilgrims made it in Massachusetts is that all of the locals were dead by the time they got there. So many factors at play but not much in the historical record.",
"Some have mentioned syphilis. It should be mentioned that the exact origins of syphilis are unknown, but what little evidence we have suggests it likely was brought to Europe from the New World. And to be clear, the syphilis epidemic in Europe killed _millions._ Without modern medicine, it's an extremely deadly disease. There's another disease shared during the Columbian exchange which is often overlooked: addiction. And this one went both ways. The old world brought alcohol, and the new world gave us tobacco. Addiction, of course, is a complicated disease, and I should be clear that there's thought to be no _genetic_ predisposition to alcohol or tobacco addiction, only _social._ Regardless, alcoholism is still a common killer in Native American communities today, and I don't think I need to explain the smoking epidemic to anyone.",
"Europeans, due to the thousand years' advantage in domestication, had immunity to all sorts of diseases. When they came to the New World, the locals were just wiped the F out by those diseases as they had no immunity. New Worlders had much, much less exposure to animal borne pathogens in close proximity and had very little immunities that Europeans didn't already have.",
"There's a book called guns germs and steel (as well as a documentary by the same name) that answers this question and similar ones in great detail",
"Guns, Germs & Steel would argue it was because those on the Old World had domesticated animals. The horse, ox, cow, donkey, dog, etc. All of these lived in close proximity to humans. Over the thousands of years before contact humans in the old world gained \"immunity\" to these diseases. Due to humans arriving later in the new world (via land bridge from Siberia to Alaska) humans were generally proficient at killing large animals. The animals in the old world had developed a heavy fear of humans and \"knew\" to attack or run. Animals in the new world were rapidly driven to extinction by these \"new\" arrivals. 20,000-30,000 years later when contact occurred, the new world had fewer animal borne disease to give and had little immunity to those they were getting. On the flip side, Europeans had a really shit time with tropical diseases throughout Central/South America, Africa and Oceania. However, new evidence turns up seemingly everyday showing humans were in the Americas earlier and earlier.",
"Meanwhile, while it takes a long time to kill, the Americas sent Syphilis to the old world with the french. That disease brought a new kind of madness and death to Europe, and may have triggered or exacerbated several significant wars. So it didn't ravage the landscape, but there was a good bit of trouble going the other way. Meanwhile a really good plague, were there any, would have killed off the sailors before they got home. So a tolerant crew could bring disease that the natives could be ravaged by, but a crew without the tollerance to some new disease would likely lead to a \"ghost ship\" or a simply missing ship by killing the crew \"too fast\". In truth the Europeans had a much richer palette of diseases to offer because of the constant invasion of Europe from all sides, so there were more candidates going towards the Americas. But there's a lot to be said for slow moving transport. If \"fast\" quasi-modern (1940's grade) air travel had been invented before the Atlantic had been crossed, then a nice plague or four might have indeed made the reverse journey.",
"1491: New Revelations of the America's before Columbus and 1493: Uncovering the New World Columbus created, both by Charles C. Mann, discuss this topic in depth.",
"There is evidence to suggest that indigenous population may have been hit quite so hard because the settlers engaged in an early form of biological warfare. For example: > Trent wrote, \"Out of our regard for them, we gave them two Blankets and an Handkerchief out of the Small Pox Hospital. I hope it will have the desired effect.\" URL_0",
"Much like vaccines, they're exposed to the disease previously so they built an immunity to it.",
"Additionally, I believe there was less genetic diversity amongst the American peoples based on the original migration population being relatively small I.e. A genetic bottleneck",
"Really great book that includes this is ecological imperialism by Alfred Crosby. My memory thinks that the Mediterranean and Europe in general was a great place for Europeans to share diseases for thousands of years, Getting a broad resistance to disease. The native Americans simply had less of a immune system arms force built up due to so little migration to and from the America's.",
"Agriculture and sewage. Agriculture made us settle down in one place, which meant our poop started piling up in one place. It was smelly and gross, so we had to find a place to put our poop, and thus we invented sewage—pits and moats and stuff. It was still open air, though, so we still got exposed to the sewage. Diseases and bacteria started forming in the sewage, and constant exposure to those diseases meant we eventually became immune (after dying in droves, of course). When we sailed across the ocean blue, we took those diseases with us. Americans at the time were nomadic hunter-gatherers—they roamed around, ate what they could kill or pick off of plants, and never settled down—so they had neither agriculture nor sewage. So they had no diseases to bestow upon us, and no immunities to protect themselves from ours.",
"I don't have a source, but I seem to remember reading that Columbus brought back syphilis which ravaged Europe.",
"Long story short - European immune systems were highly developed due to all the animal shit they lived around, in densely packed cities, the shit harbours all kinds of nasty diseases and the dense cities make it easy to spread.",
"Because there was no disease that could turn into a deadly plague to contract. There were a few STDs that make their way through the colonists and back to the old world, but that's about it. The major reasons being lack of large and tightly packed cities, and much contact between animals, as they had no real domesticated animals to speak off to get. So the situations in which plagues are created simply weren't present in the Americas, so there never was an Americapox."
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6zfk5f | Why is B.C and A.D used to measure years in the past when only part of the world's population follows Christianity? | Repost | explainlikeimfive | {
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"Because for a long time, a huge portion of the educated elite in western europe were part of the Christian church. So the vast majority of historical records and discourse were done using that calendar. Then, since everyone was using it, it stuck, since there isn't really a good alternative. Secular folks sometimes call it BCE (before common era) and CE (common era) instead of BC/AD, but they use the same point for Year 1 so that there is no confusion between the calendar systems."
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6zgvhj | Why do we have different electrical outlets on different continents? It seems electricity was discovered and then everyone went different ways with it. Is one setup better than another? | Repost | explainlikeimfive | {
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"Before electricity, there were no fast ways of communicating across continents. When electricity was discovered within a nation, they never thought of waiting months to ask other nations about how they plug in devices. The nation just wanted to take advantage of the new invention as soon as possible! Therefore, there are so many plug standards as the first nations consulted their own engineers and scientists to make their own working plug. Once people found out there were different standards, it was too late to change since so many buildings and devices have already been converted to one type of outlet. In terms of different setups, there's two major kinds of standard voltage depending on the country: 110 Volt and 230 Volt. 110 V is the standard in North and Central Americas + western Japan. 230 V is found everywhere else. 230 Volt is more efficient power-wise but more dangerous due to the high voltage. 110 V is safer but it cannot supply as much power (ovens and refrigerators may need a separate high voltage plug). ~~Luckily, there are no plugs that can plug into both which is an easy way to burn out your device.~~ Nevermind... there are definitely plugs that can plug into both... check your adapter specifications and/or read your manual to prevent your devices from dying when using the wrong voltage! Both of these outlets supply alternating current meaning the voltage goes up and down with time. They swing at a cycle of 60 Hz (cycles per second) in countries with a 110 V standard and 50 Hz in countries with a 230 V standard. This had influence on the refresh rate of TVs since TVs fixed their refresh rates to the power frequency to prevent strobing effects that would occur if the frequencies were mismatched. Nowadays with digital content, most TVs have been standardized to display at 60 Hz refresh rate. Edit: Clarifications in the last paragraph.",
"Tom Scott argued that UK plugs are superior because if the wire gets yanked the last thing to go is the Earth wire apparently making it a bit safer. I'm not so sure, I do know that if you step on an upturned UK plug you are going to come out with a long string of four letter expletives. That shit seriously hurts.",
"Dunno if its technically an answer to the question but Tom Scott has a good video about the UK plug/outlet design URL_0",
"Well voltage and frequency of AC supply varies by country so having different sockets is an advantage so you dont blow shit up plugging in the wrong one. Also some countries have different safety standards for there plugs. The UK has arguably the best sockets in the world but other countries didnt feel the need to develop them the same",
"It is very hard to change systems once one is adopted. Ontario Canada had electric power since the 1890s, the Brock #1 power plant at Niagara Falls. But there were other private systems before that. So Ontario at one time had 2 systems, 25cyles per second and 60 cycles per second. This became so unwieldy that in 1950 they switched everything to 60 cycles. Teams of electricians went from door to door, replacing the motors in everyone's washing machines, refrigerators and other appliances. This cost a great deal of money, and inconvenience for a lot of people. Today it would be even harder and more costly.",
"UK plugs are superior as far as safety is concerned - they have a fuse in the plug, pins are rectangular for best contact surface and the ground pin is longer so it connects first and disconnect last. The sockets are better too - they have individual on/off switches and shutters in them for protection, you can't reach live wire unless ground is plugged in. They are rather cumbersome and take a lot of space though. Euro plugs are a bit worse but still good, can't really reach live wire unintentionally, US ungrounded plugs are quite possibly the worst there are.",
"Electricity was discovered and the tech around it was invented before communication between countries was easy. Things were still done by letter or in person so communication between neighboring countries would take days or weeks, while that between the continents could take months. So every country came up with their own standards as tech was invented/re-invented by their scientists. By the time communication was easy they already had different standards firmly established and so it was not reasonable for them to go to a uniform standard. In fact the only reason that Europe has for the most part one standard is that they had to rebuild after WWII and so took the opportunity to make things more uniform."
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