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|---|---|---|
How do marine organisms internally produce omega-3 fatty acids? | [
"Well fish can't synthesize omega-3 fatty acids *de novo* themselves, so they must obtain the essential FA, namely α-linolenic acid, through their diet of smaller fish or primary producers like algae that can synthesize it *de novo*. The fish then convert it like we do, with Δ6-desaturase, elongase, and Δ5-desatura... | [
"To add a concrete example to what's already been stated: [The Sahara desert fertilizes the Amazon rainforest.](_URL_0_) Equatorial trade winds carry mineral dust (carbonates and oxides, mostly) from the Bodele depression in the Sahara to South America, significantly increasing the productivity of the Amazon basin.... |
What is Game Theory? | [
"It is the mathematically study of adversarial decision making. You have some situation, where participants have competing goals and make decisions based on reaching their goals and preventing others from reaching theirs. Game theory allows them to devise an optimal strategy, taking into account the other player's ... | [
"This CGP Grey video does a really good job of explaining it all. _URL_3_"
] |
Writing a persuasive speech in the favor of Nuclear Energy plants, what's the coolest, not well known, fact you know about Nuclear Plants that I can throw into my speech to spice it up? | [
"Nuclear power plants release less radiation and radioactive particles into the environment than coal fueled power plants. Radioactive materials exist all through various minerals, so standing next to a marble wall at the courthouse will expose you to more radiation than just outside the fence of a nuclear power pl... | [
"I would make it so that either: all teeth are replaceable, so can be pulled out and regrown or teeth are smoother with few fissures so less cavities can form. Having fewer but maybe larger teeth might help too since you have less spaces between teeth for food to get stuck Depending on how far you can take it, I wo... |
why do babies not respond to noise whilst sleeping the same way adults do? | [
"They do. Just like adults some are heaver sleepers than others and sometimes they wake up but go back to sleep right away. I have 2 friends both who had babies at around the same time. One friend cannot even have the TV on downstairs or the baby wakes up. The other friend had 3 guys over drinking, playing video ga... | [
"Your rat's brain is more developed at this point. Humans have huge brains that need a lot of time to develop, and due to our narrow birth canals, we also have to be born fairly underdeveloped compared to other animals. Your two year old's brain is not yet in a stage where it can make the sort of long term connecti... |
Do stable elements ever decay? Even a little? | [
"In about 10^1500 years it may [turn into iron](_URL_0_) due to quantum tunneling to arrive at a lower-energy state. It is also possible that protons decay. They might never decay at all, and if they do then their half-life is longer than about 10^34 years. If they do decay then all matter will disappear long befo... | [
"The Universe is a dynamic place. Stars have been observed to move around, some quite fast. We have seen a number of [supernovae](_URL_6_) throughout the centuries, including many in other galaxies in more recent years. [Supernova 1987A](_URL_3_) has changed since we first saw it (this is really the post-supernova)... |
What is Third Way philosophy? | [
"It's a mix of capitalism with big-government social programs, basically a version of Liberal Democracy. The idea is that while communism and pure socialism don't work, neither does pure \"every man for himself\" capitalism. Alongside free market we can have social services that provide people with job training, se... | [
"_URL_0_ The wikipedia article is excellent and better than any of the answers in here so far. If you have specific parts you don't understand, ask away and I can help explain them to you."
] |
Why is "they are" correct grammatically, while "everyone are" is incorrect, when they are both used as singular pronouns? | [
"Think of 'everyone' as 'each and every one'. 'One is', singular. 'They' is used when there is a plurality of people *or* when there are plural options for addressing someone and you don't know which to use. 'They are', plural."
] | [
"Imagine that you have a number of (bees/participants/sources), each of which has 1% accurate, useful information and 99% random noise. Individually, the noise drowns out the information. However, if you add together all of your (bees/participants/sources) in the right way, the information accumulates while the noi... |
What is biosemiotics? | [
"There are processes of \"knowing\", \"meaning-making\" and \"understanding signs\" etc. that happen in animals, or at the cellular level as well, right? Biosemiotics is a field that studies all this, using theory from biology and semiotics both. Intracellular communication, stuff going on with hormones and respons... | [
"The premise is not actually that complicated; you use a semi to separate two disparate but not unrelated sections of a sentence."
] |
Many middle-class families in TV sitcoms from the 50s - 80s had live-in housekeepers. (Brady Bunch, Hazel, the Jeffersons, etc.) How common were live-in housekeepers in real life? Why don't upper middle-class families have them now? | [
"None of those families were middle class. But hired help has certainly gotten less common. The cost of labor went up, faster then the wages of middle class families. With stronger minimum wage laws, welfare, and subsidized education, there was less unskilled labor willing to work for low enough wages to make them... | [
"A good way to track the popularity of languages in an area is seeing how many newspapers were published in that language. Newspapers are more regional than books, and require more of a core language readership to keep going, so if there's a German newspaper around in an area, there's German readers around. My libr... |
Are illegal/undocumented immigrants as a whole a net benefit or burden to the US? | [
"I'm not sure how measurable it is overall. One the one side, illegal immigrants typically provide very cheap labor, which contributes to lower costs products and increased revenue for companies that use them. On the other side, they typically don't pay all of the same taxes as most people, despite using the same... | [
"This submission has been removed because it is [soapboxing](_URL_1_.), [promoting a political agenda, or moralizing](_URL_0_). We don't allow content that does these things because they are detrimental to unbiased and academic discussion of history."
] |
What physical/chemical property makes certain rocks "harder" or "softer" than others? | [
"That depends on what kind of rock and what you're talking about. The strength of single crystal depends on the atomic structure of the crystal and the strength of the chemical bonds in it. But rock is not normally a single crystal, so it usually depends on the larger scale structure. For instance, sandstone would... | [
"Water is really great at transferring heat energy out of you (that's what the sensation of cold is, the transfer of heat out of your body). Air, not as good. & #x200B; Put 2 benches in a room at, say 20 degrees C. One is made of stainless steel, one is made of wood. & #x200B; Both of them will measure at 20 degr... |
What makes "outlet mall" stores different than regular retail stores? | [
"Historically, outlet stores sold factory seconds. This varied from company to company, but it would usually be a mix of returned merchandise, \"irregular\" items and last-season's/discontinued items. These were all things that the company didn't want associated with their brand, but still wanted to try to recoup s... | [
"Different gasoline taxes. Different distances between the nearest refinery. Different blend requirements for the gasoline(California). Different requirements on who's allowed to pump gasoline into a car(Oregon/New Jersey). Different minimum wages. Different property values for a gas station sized plot of land. Dif... |
How is it that my Cholula Hot Sauce (or any condiment, for that matter) has zero calories per serving? | [
"The serving size for hot sauce is probably very small, a quarter teaspoon or so. It there's less than 5 calories in the amount of a serving, the FDA allows it to be rounded down to zero."
] | [
"the science behind the phenomena or the measure? The phenomena is that particles absorb heat, but the rate of heat exchange is proportional to the temperature difference (energy rate of transfer = temp difference * mass of thing * specific heat capacity of thing). So heat exchangers commonly run fluid through to c... |
Why are large physics detectors like LHC and Super K buried underground? Is it because they are dangerous? | [
"SuperK is underground to shield it from ambient and cosmic backgrounds. The LHC is underground to shield to the local environment from it. Even if the amount of synchrotron radiation is much less than LEP, you still have other losses from collimators and collisions."
] | [
"Ignore useful. How a discovery is used is of zero concern. What is important is the experiment and proof of concept. If successful, it will prove our understanding of matter and the universe, if unsuccessful we will study why and expand our understanding of the universe. It's like the discovery of electricity, wh... |
When we're trying to fall asleep, why do we fidget? | [
"\"Hey Brain, are you asleep?\" \"I don't know Brain, let's ask Arm.\""
] | [
"It is supposed to be a natural reaction that our ancestors used to survive. It would keep them away from the nests of dangerous insects such as termites. It was the body's way of trying to avoid the danger and keep alive. If you believe in evolution you could say that it is part of evolution."
] |
How do street signs get their names? | [
"It varies, in some areas, particularly in planned towns and cities, streets are given numbers and named sequentially, so the west-most north-south street might be called 1st Street and the East-most north-south street might be named 10th street, and east-west roads would be named similarly, although they might be ... | [
"In short (I'm over-simplifying here) the ICANN takes care of internet addresses. This has been in the US for years, but after the NSA spying scandal they decided it was time to make some changes. See also: _URL_0_ It was always the plan to be global, and not tied to one specific country's government. It was never ... |
Just bought a microscope. A couple questions... | [
"the oil is to put in between the highest powered objective and the slide. Make sure you don't crack your slide or scratch your objective. This would also help you to see clearly on the highest power. Some really simple things: your cheek cells stained with iodine (optional). A thin slice of celery or the clear ski... | [
"Glass microbeads are filled with the scent desired, perfume or whatever. The beads are mixed in with a \"glue\" and painted onto the card. When you \"scratch\" you deform the beads, causing them to break and release the smell."
] |
Why is mint the only acceptable scent for breath? | [
"It is popular because the mint plant contains menthol. Menthol is a substance that triggers the cold sensitive receptors on your tongue, skin, airways and the like. It gives a sensation of coolness that people associate with freshness. Manufacturers of toothpaste, chewing gum, mouthwash etc made it an industry sta... | [
"Bacteria on/in your skin metabolize the minerals in your sweat and create a by-product. TL;DR: sweat is bacteria farts."
] |
Why do a significant number of Christians (and other religious groups) believe in Heaven, but not Hell? | [
"In every major religion I know about, people pick and choose the portions they wish to believe in. Heck, even among scientifically proven facts, people act this way -- so it's not a surprise they do so in faith-based situations."
] | [
"As a US teacher, here's what I've found. America is in an uninterrupted chain of nostalgia for the previous generation's form of schooling. Having had no major disruptive events to our institutions, we still essentially pine for the one-room schoolhouse model. Every school board I've seen has proudly boasted that,... |
Why don't the door close buttons on elevators ever work? | [
"They will work for maintenance personnel if you have a key inserted. Otherwise it is just a [placebo button](_URL_0_) that makes you feel like you're in control."
] | [
"I posted this before elsewhere: Deep inside the seatbelts mechanism there are two--what I will describe as--half gears. They look like gears, with a few teeth and such, but are split in two down the middle. These halves spin together as the seatbelts is pulled, but the motion of quickly pulling the seatbelts force... |
Why do pornsites always have this junk or spam ads on their websites instead of normal ads regarding their huge traffic? | [
"Porn sites have a very limited pool of advertisers to pull from. The majority of advertisement networks will not deal with them because of their site content. I'm president of a non-profit that does conferences and workshops related to non-traditional relationships and sexuality. Our events totally above board, no... | [
"Sugar tastes good. When faced with a choice between that which is smart and that which is pleasing, most people will spend their money on the latter. A business exists to sell people what they *want* to buy, not what some might feel they *should* buy."
] |
What makes toilet paper dissolvable and safe for the toilet versus paper towels/kleenex/tampons? | [
"Toilet paper is made with short fibres when compared to facial tissues, paper towels, tampons and even writing paper. The short fibres allows for more rapid decomposition and loss of integrity with the addition of moisture. But companies have to balance between short fibres for decomposition in sewage and longer f... | [
"Explosives used to consist of lots of different mixtures, and it was hard to express just how much energy would be released with a particular explosive. They weren't very consistent. Trinitrotoluene is one chemical that explodes via a predictable chemical reaction: a certain amount of TNT always corresponds to a c... |
What causes genetic changes that alter an animals appearance so that it can camouflage within its environment? | [
"The changes themselves spread because they're successful. White color might spread among mantises that hunt in white orchids, because they blend in better. You might ask, \"How do the changes happen in the first place?\" Well, the changes happen because children are not perfect copies of their parents. They're a r... | [
"The percentage only considers the percentage of base substitutions in the DNA not the actual amount of DNA that is similar. Scientist look for similarities between genes, then when they find them, they count the number of times one DNA base has been replaced by another. If there is a strand of DNA that does not ha... |
Would water pressure in the ocean prevent small objects from sinking to the bottom? | [
"A penny would sink. [The density of water at the bottom of the Mariana Trench is only ~5% greater than at the top.](_URL_1_) Liquid water (and liquids in general) are [not very compressible](_URL_0_), especially when compared to gases."
] | [
"When a lot of stuff floats around it tends to group up... as those groups form they get more and more attracted to eachother. The more stuff there is the more gets attracted (gravety). Eventually there is so much stuff that the middle gets very hot! Everything there turns into this super dense ball. it keeps pulli... |
How is it that if someone calls 911 as a prank or accidentally calls then hangs up without talking, they will track down where you live and send the police to your house. However, why hasn't everyone that has called 911 to SWAT a gamer on stream been tracked down, arrested and charged? | [
"SWATTERs typically spoof the location/number that they are calling from. This makes it a little more difficult for law enforcement to determine who placed the call."
] | [
"> Ray Diaz got prisoned for sexual assault No, he wasn't. He was **arrested and charged** with sexual assault. This is just the first step in the criminal justice process. He will eventually go to trial, where his lawyer and the prosecution lawyer will argue about the evidence against him in front of a **judge and... |
How does construction engineers / architects make sure a building won't collapse when they're designing it? | [
"/u/sleighur answered this well, but to add: Engineers will know their materials, and have massive charts to consult. What foundation works best with this soil? What are the environmental hazards (earthquakes? heavy rain? ice and snow?)? What does the client want (big windows means big clear spans which means big s... | [
"Basically, in countries that have private ownership of land, land surveyors give their opinion on where property lines actually are on the earth. We research deeds, maps, etc. to determine where the lines are thought to be and then go to the property to find evidence of where the original survey marked it. The ins... |
Why is there so much hatred towards Jar-Jar Binks? | [
"Pretty much because he was an unnecessary, unbelievable (in a bad way) character who got way too much screen time. The creature is clearly an imbecile, but features in the majority of the film and somehow ends up victorious and revered, despite being a threat to the Gungan security, safety and, when he becomes a f... | [
"\"Just about everyone here\" Where is \"here\" for you? It sounds like your question's premise is based on a small sample set based on personal observation. Before your question is addressed, you should be making sure the premise is valid..."
] |
How close do two objects have to be for the objects force of gravity to act as one like one big object? | [
"Here is the formula for an electric dipole (two things close together). Gravitational is near identical other than a few constant for the most part. _URL_0_ Basically the answer is never. Ignoring the constants (which are the only real difference) only way to make it appear as a single charge (or mass) is to take... | [
"The [glycocalyx](_URL_1_) plays some part in this. Essentially, sugars and proteins in the cell membranes protrude out and carry charges with them. These can be organized in such a way to keep cells appropriately distanced from each other so that they don't fall apart or merge. There may be other factors, but thi... |
If something has its colour because light get deflected, does that mean that an object in a fully dark room has "no colour"? | [
"Depends on what you mean by \"has colour\". A blue scarf doesn't stop having the ability to reflect blue light just because there's no light on it right now."
] | [
"[Here is a nice explanation](_URL_0_) from r/askscience. tl;dr: From a particle perspective, we add up all of the possible paths the photon can take, and they almost all cancel out, leaving only the angle that obeys the law of reflection. From a wave perspective, the surface acts like a [diffraction grating](_URL_... |
Reddit, my bedroom is directly above my kitchen. Every time someone switches on the microwave, my internet freezes for whatever the duration of the time set. Why is it doing this, and how can I stop this happening? | [
"Interference. You can stop it by using a hard-wired connection instead of wireless. Failing that, reposition your wireless access point or your microwave."
] | [
"Interference from heat waves in the air. Even cold air has enough energy to disturb and refract the light."
] |
Would a "Euthanasia" Roller Coaster really work? | [
"> for dealing with over population yes, overpopulation is a problem, but culling humans isn't the answer! anyway, you and the guy are correct in the part about fighter pilots, but you only experience \"g-force\" when turning in a jet aircraft, and the force is over quickly. what i think would almost certainly be ... | [
"This has been done before, with animals. Here is a video **allegedly** showing an old Russian experiment done with a dog. It looks real to me, but, then so did *The Wizard of Oz*. Warning, it might be disturbing and upsetting to watch. _URL_0_"
] |
How can the FBI seize a website? | [
"The website is stored on a server which is physically located somewhere. If it's located in the United States then the FBI can get a warrant to take possession of it (or at least the section of it that the website is on) to shut the service down. If it's located in another country then they have to cooperate with ... | [
"My huge question is on what legal grounds they were shut down? They're just like youtube, they comply with DMCA. What the hell is the difference that made them get shut down?"
] |
What exactly are memories and how are they stored and recalled? Why are we unable to recall everything? | [
"I have a degree in cognitive science, and I can tell you that the answer is very simple. Nobody knows, and we're not even close to figuring it out. All we really know is that there are certain structures in the brain that are critical to memory storage and recall, but we have very little idea how they actually w... | [
"Imagine you're trying to find a coffee shop in a city. If you've been there recently, it should be pretty easy to find. If it's been 10 years since you've been to the coffee shop or the city, it might take you a LONG time to find. It also might take long to find if you've been to other, similar coffee shops in the... |
How can DNA testing be used to confirm the identity of long deceased bodies, such as that of Richard III? | [
"This has been asked a few times already. _URL_0_"
] | [
"I'm not a Tudor historian, but I expect the most relevant part of the article is the paragraph buried in the middle that reveals the source for this conspiracy theory is an American novelist with a new thriller to sell (with some obscure quotes from Bram Stoker, another fiction novelist, thrown into the article fo... |
Why did New York City merge multiple subway companies into one? | [
"The problem is that if I want to get from A to B, I don't have a choice of which line I take. If company X provides a better service but doesn't run the line that takes me from A to B, that's no use to me. I'm not going to walk half a mile to station C to get a train to D and then walk another half a mile to my fi... | [
"Competition among restaurants to show that they were giving the customer the best value for their dollar. \"Well, this place gives me this much food for $5, but that other place gives me even more for the same price!\""
] |
How accurate are calories per serving on packaged food? How would you test it? | [
"You test it by burning the food/ingredients, which tells you how much \"energy\" (aka calories) is in it. As for accuracy, that really depends. For labeling purposes, they round down to the nearest 5 or 10 calories."
] | [
"Get a feel for what you are reading. Ask yourself do all their arguments follow? Are they sometimes making leaps of logic? Are they priviliging/relying one group of sources, if they are do they explain why? What perspective is the book written from, how might this affect the focus of the book? Are they making bad/... |
Agnostic vs. Atheist | [
"A lot of it depends who you ask. Using the most common definitions of those words, an atheist is someone who doesn't believe in gods, and an agnostic is undecided. Note that atheism doesn't imply certainty, just lack of belief. I don't believe there is a wombat living in my garage, but I could not claim 100% certa... | [
"There's a great explanation about the switch in [this](_URL_1_) post. Edit: Also [here](_URL_0_)."
] |
What causes some people to be more tolerant to extremely cold or hot temperatures? | [
"Some of it also has to do with what you are used to. Here's an anecdote... I am from the frozen part of the northern midwest. In the winter, it rarely gets above 15 degrees F, and wind chills are often below zero. I lived in this area for 13 years before I went to college in the mid-south (Kentucky). During the fi... | [
"because the spices contain capsaicin. Capsaicin binds to your receptors, and literally makes your brain think youre on fire, which sets of all of these alarms, so your nose starts running, you start sweating alot more, you crave something to drink. Just remember, water doesnt work as its polar, while capsaicin is ... |
Are our ears unable to detect pitches beyond human hearing? Or is our brain designed to ignore those pitches? | [
"The receptive region of the ear responsible for detection is the cochlea, the cochlea is kinda like a single tunnel forming a U shape with the receptive region in between the 2 branches. When detectable frequencies enter the ear they are sent into one end of the tunnel and cause a certain area of the basal membran... | [
"Not really. Yes we can breathe below atmospheric pressure, but there is a limit. I seriously doubt we can breathe a 1/4th ATM. Breathing is a pressure system. When you inhale it is because your lungs are at a lower pressure than atmospheric pressure. The opposite goes for exhaling. The limitation we have is how m... |
What is happening when food becomes freezer burned? | [
"Are you asking about the taste or the dried out texture? I have no answer about why freezer food sometimes has \"that taste.\" As to why food dries out: ice sublimes: goes directly from solid to gas like carbon dioxide AKA \"dry ice\". You can usually see it redeposited on the inside of the container. Over time e... | [
"I used to work in retail and the answer is poorly. We can't possibly track any given customer across hundreds or thousands of potential stores. The ban really has two purposes: - It is a deterrent - many customers are too afraid of consequences to show up at the store again. - _If_ we do recognize them, we have ju... |
Why was the Japanese army's weaponry so feeble in comparison to that of the US Army during WWII? | [
"That's a rather general question. Aside from the infamous Type 94 pistol, Japanese small arms were not poor by any means in fulfilling their role in combat. However, the US did create an advantage with the introduction of the M1 Garand, as the Japanese were not used to the amount of firepower American units had, l... | [
"This has essentially been answered by the preceding comments, but what hasn't been contributed is this: _URL_0_. Muster and enrollment records, transfer lists, honours lists, etc, for the period of 1730 through 1898. Worth having, OP, if you're writing or researching the topic academically. To succinctly summarise... |
What is the process of making a video game? | [
"I recommend /r/gamedev But it(at least indie, or small scale simplified): -the idea is made, and a rough draft is created if an engine is established(creating your own engine is very costly both $$$ and time) (Currently Unity and Unreal Engine 4 are the big ones) -Basic assets are made(everything you see in a game... | [
"Much of the core code can be kept, but the parts interfacing with the hardware has been to redone. There are engines and frameworks which do this for you, but you'll likely end up having to do tweaks as well. Language matters too, of course. Technically, the managed languages should have an easier time (jvm, .net)... |
How come we never forget how to cycle? | [
"You *can* forget how to cycle. You very well can lose the memories associated with riding a bike, just like you can lose any memories. I would argue that while completely forgetting is probably not likely, you're much more physically coordinated in general as you get older. This means that even if you do completel... | [
"Put Simply - Because your brain isn't a computer The \"organic computer\" metaphor is really a bad metaphor for the human brain. Our memory isn't stored like a computers, so we can't do something like iterate every single word we know... but we can also hold a conversation which is something computer struggle to d... |
Was heat exhaustion/sunstroke a big problem for the knights who fought in crusades? | [
"This certainly came into play in battles in the Levant. It was a crucial factor in one of the most famous battles of the crusades, Hattin. The crusader army under King Guy was weakened and killed off as much by the heat and dehydration as by Saracen steel and arrows. Saladin cut the crusaders off from any water su... | [
"This has essentially been answered by the preceding comments, but what hasn't been contributed is this: _URL_0_. Muster and enrollment records, transfer lists, honours lists, etc, for the period of 1730 through 1898. Worth having, OP, if you're writing or researching the topic academically. To succinctly summarise... |
If the probability of landing on any one space on a monopoly board is equal, why do people land on Boardwalk much much less frequently? | [
"Probability of landing on any one space in monopoly isn't equal at all. There are actually a lot of studies on the subject. Given dice roll rules, cards and stuff that transport you around, rules that throw you in jail etc. btw the most cost-efficient property to buy is orange"
] | [
"If I understand your question: The orbits are not just represented as being in the same plane (parallel paths) for ease of communication. The orbits are, in reality, all roughly in the same plane. Illustration: _URL_0_ This is due to the fact that the planets formed from the matter of a protoplanetary disk. There... |
How did American Football become a winter sport? | [
"The sport got its start in the Ivy League and other northeast colleges. All of whom only generally began after September 1. So add on time to find a squad, and to get a schedule together, it's not uncommon to see early seasons begin in late September or October. Then schedules only became longer as more schools s... | [
"Back then people still needed jobs, now they dont and can practice harder for longer. And science helps by showing then methods on improving motions. You cam find cool videos on youtube"
] |
Why do foreign objects (ie a stray eyelash) feel 100 x bigger when it is in your eye? | [
"Eyes and tongue are highly delicate and specialized organs. Humans heavily rely on sight and taste for their awarenes and survival. These organs must be priority number one. So any object that happens to be in the eye or in the mouth is deliberately exagarated and the sensation is uncomfortable because one must re... | [
"Your sinuses and ears are connected via a thin tube called the eustachion tube. Sometimes the tube gets kinked like a hose and the free flow of air is blocked. A change in pressure outside your head, like flying in a plane, can make the air stuck in your head seem pressured. Yawning aligns the tube, allowing the e... |
Forts on otherwise uninhabited islands. Couldn't the bad guys just...sail another way to the mainland? | [
"Forts are rarely out in the middle of nowhere. They generally are guarding a narrow access point, be it the opening to a waterway or simply the one section of water deep enough for large warships to sail through. They can also serve not to attack ships directly, but to provide a fortified position for your own de... | [
"There is actually a [PBS documentory](_URL_1_) coming out on the 23rd this year - Starts on May 21st. Similar things had been used by the British prior in the war, but as i remember it the 23rd was made up of [set designers](_URL_0_), (magician's?) and similar artists. It was a huge misdirection, not just the i... |
"No one was harmed during the making of this film" - what do they do when someone does get hurt? | [
"Do they actually even write this at the end of films? For animals, definitely, can't remember ever seeing it for humans though."
] | [
"Their claim hasn't been verified in any scientific way. If I gave 10000 people a sugar pill and 1000 of them lost weight I could legally claim that the pill helps with weight loss. It wouldn't make the claim true, and the results might not be repeated in a larger sample population. The disclaimer would keep people... |
Why don't places like McDonalds' and Burger King have delivery services? | [
"Mcdonalds has delivery. It's called McDelivery. [Check it out](_URL_0_)"
] | [
"So, I don't know if you know this, but Blackstone did just what you are suggesting. After the housing crash of 2009, they went out and bought up homes in different cities. They put them all under the umbrella of a REIT (real estate investment trust) called \"Invitation Homes\" and then spun it out in an IPO a few... |
Why don't anti-trust laws stop companies like Comcast and Verizon from monopolizing cable, internet and other services? | [
"They're natural monopolies which exist because in their specific industry, competition is unreasonable. There are too many barriers to entry. They have special permission to act as a monopoly, and they are (theoretically) strictly regulated by the government in order to keep them from abusing customers. Obviously ... | [
"Let's say toll roads are run by Wal Mart. They then offer a discount - you can drive to Wal Mart for free, but still have to pay a toll when you go anywhere else. Sounds good, right? But then next year they double or triple the toll. Soon you can't afford to shop anywhere EXCEPT WalMart. Every other store then go... |
What did nomadic horse archers use to make their arrows? | [
"Hi, this is not to discourage other answers but you might be interested in [this post](_URL_0_) by u/krishaperkins"
] | [
"**If you're new to the thread, please don't post the Mythbusters episode again. Mythbusters is entertaining but it's not history (or more specifically, it's not historical proof of anything.)** The short answer is no, not that we know of. /u/davidaop, our pirate expert, and I have both answered [questions about th... |
Why do I fall asleep in class, but feel energized the rest of the day? | [
"Because class is boring, and you don't have the opportunity to do something different. You're given a choice: Do something boring, or go to sleep. Once out of class you have a range of options, not previously available. As for a tip: Put your elbow on the desk and lean your head on your hand. This means if you do ... | [
"If it isn't already in your (or the doctor's) plan - I highly recommend asking to have your thyroid hormone levels checked. Underactive thyroids can cause so many random symptoms to appear and be different from one person to the next. Caffeine is often recommended to be reduced or eliminated if the thyroid is abno... |
Why is it when one tooth hurts, your entire mouth hurts and it's hard to find which tooth is causing the pain? | [
"Pain is a projection of your brain on the body part causing it. This means that if it receives a signal from say your arm, it makes you conscious about this pain and the brain tells you that it's in the arm. Things can go wrong with this system though. Sometimes, the nerves that relay pain stimuli from one part of... | [
"You've pretty much got it. When you combine a bunch of ingredients in a flavored liquid, at first the flavors of the liquid will either just coat the pieces or barely penetrate the surface. As you let it sit, the flavors penetrate deeper into each piece of food, and each ingredient starts to give up its own juices... |
How the idea of dragons first came about | [
"The first dragon stories are far too old to accurately date or determine their specific origins. However, we live in a world where ancient skeletons with ten inch teeth occasionally erode out of hillsides and fireballs from space streak across the sky. Your typical bronze age person wouldn't really know what to ma... | [
"We make good guesses based on what little examples of skin have been preserved as impressions in stone, and what other animals we know that are similar are like. As we learn more, our guesses get better and hopefully more accurate. This is why we now believe that many dinosaurs had feathers, when we didn't before.... |
How is there "zero gravity"? | [
"We don't tend to use the term 'zero-gravity', pretty much for that reason. You're always gravitationally affected by all of the mass in the universe, a tiny amount. Scientists would more often use a term like '[microgravity](_URL_0_)', to indicate that while there is some gravity, it's so weak that you can effecti... | [
"Exposure to unfiltered sunlight and near-vacuum conditions, most likely. Conducting experiments on site would definitely pose a challenge though."
] |
No CAPTCHA reCAPTCHA | [
"It tracks your mouse movement and compares it to average mouse movement t by other humans and mouse movement done by bots. The specifics aren't given out because then it wouldn't work because the bots would be programmed to move the cursor like humans."
] | [
"From our standpoint as users, nothing at all. From Reddit's standpoint, one of them means the backend computers told them \"sorry too busy\" and the other means that the backend didn't respond at all."
] |
Why are rappers (and other musicians) allowed to admit to committing crimes in a song? Why aren't they investigated/prosecuted? | [
"They are making art and it's protected as such. Keep in mind music tells stories. Not true ones, necessarily. Treat each song like a new fictional person telling you something."
] | [
"Many cop/lawyer shows use real rvents to inspire episodes. This keeps the series current and relevant for viewers interest, can actually be used to inform the public, improves show ratings, and reduces headaches for writers trying to come up with ideas. But the show makers want to be sure it isn't thought to be \... |
Why is plastic surgery for hands so ineffectve? We see many ageing celebrities with young-looking faces, but their hands always give away their true age. There's surely a market for it, so what's holding it back? | [
"You ever notice how people with a lot of work done on their faces can't be very expressive because their faces don't move as much? Now imagine the mobility in your hands is that limited. People are willing to sacrifice some ability to move their faces (which everyone will see and notice) more than dexterity in the... | [
"But people of all ages like toys too! Cars, electronics, handbags... It's just that we only call them toys when kids like them."
] |
why does people's voice change as they age? | [
"It's kind of similar how the rest of your body ages-slower movements and less strength. Pitch possibly may be reduced as your body ages, as well as the quality in all. Throughout puberty ages in males, the larynx tends to grow larger. They have a bit of a bigger change than a woman's larynx, making the pitch of a ... | [
"Or in my father's case, how come his seasonal allergies went away when he turned 45?"
] |
Can light particles ever collide? If so, what are the effects? | [
"A Photon (aka single light quant or electromagnetic wave packet), can not just interact with other particles, e.g. through [some form of scattering](_URL_0_), it can even interact with itself (or other photons) through interference (waves being cancelled or amplified, just as you said). The reason for this lies in... | [
"It's not voodoo magic. It's kind of like brushing your hair. When you get up in the morning, your hair (assuming you have more hair on your head than I do) is all tangled from tossing and turning and all that other jazz. This is what regular light coming from, say, a light bulb looks like. It's all tangled and sca... |
What is the science behind 'cooking' scallops with lemon/lime? | [
"Fish, meat, poultry etc. are made of proteins. When protein is heated enough it \"denatures\", which changes the folding of the protein molecules - the meat becomes harder, changes color, and so on. Exposing proteins to acid (lemon juice) also denatures proteins. So that's why soaking scallops in lemon juice has a... | [
"Imma answer your question, but first let me tell you about this time I watered the lawn on a warm july afternoon, there were clouds in the sky and childrens laughter.... ok seriously, who knows, maybe they just like to hear themselves type, or create an emotional connection to the recipe, perhaps they are just kil... |
How do antibiotics work? | [
"Antibiotics mainly comes in 2 flavours, The penicillin (or beta-lactam) class of antibiotics block the action of the protein DD-transpeptidase, this protein is responsible for building the bacterial cell wall, without this protein, when bacteria divide, they are unable to cover the breakage point and the bacteria'... | [
"Could you be more specific? This is an *extremely* broad question that would take forty hours and several textbooks to properly explain."
] |
How does mobile "Direct Deposit" work for checks? | [
"You take pictures, you enter amount, you send it in. They use a computer to analyze the check and the serial numbers to see if it's a true check, they also check the amount as well of course."
] | [
"Is this an attempt at viral marketing? On the exact link you provided it says: > Infiniti’s Lane Departure Prevention system uses a camera to monitor the distance between the vehicle and lane markings. If the vehicle drifts, the system signals a warning and can help the driver return the car to the center of the ... |
Why isn't the regrowth of nerves and other key cells using stem cells not more popular or more researched if it works so well? | [
"The ethics of Stem Cells are a little fuzzy. The best Stem Cells for use in Humans come from Human Fetuses. That means harvesting cells from freshly dead babies. Any situation that leads to a researcher extracting fresh stem cells is going to stumble afoul some dark decisions by one party or the other."
] | [
"> If 90-100% of people wanted meth-with its known negative effects-legalized how can the government still refuse? Because, in our government, the citizens do not have the power to actually enact such measures, except through Constitutional Amendments directly (and even that is a weird process that we've never real... |
The economy on Earth in Star Trek. | [
"They live in a post scarcity world. Basically they have an unlimited supply of food, energy, etc so no one *has* to work but they do what they truly want to. It really helps if you don't think about it."
] | [
"It's relative. If the rates for pounds are more than dollars, one might sell dollars to buy pounds to get higher interest. This makes the cost of dollars go down (many sellers) and the cost of pounds of up (many buyers)."
] |
Is it possible to see a year into the past by placing a mirror half a light year away from earth and looking at it with a telescope? | [
"In principle, if you had a large enough mirror placed half a light year away from Earth, yes, you could see a year into the past on Earth. Place it ten light years away and you can see 20 years ago on Earth, and so on. Note that you can never see farther back in time than the mirror's launch date from Earth, becau... | [
"That's a hard question, because you're asking for a hypothetical analysis of a hypothetical behaviour of a hypothetical particle. Based on what we know right now, reverse time travel is not achievable. However, when things change, so will our understanding. No-one knows what those changes will be until they happen... |
If everyone says California is so expensive, how do people afford to live there? | [
"Some make so much money it doesn't matter -- if you make $200k/yr, it's not a big deal. Others request and accept cost of living adjustments from their employers. -- in Kansas, a position might be worth $60k/yr. In SF, it might be $90k/yr Others just live in small places, drive small cars, and enjoy the sun."
] | [
"They don't make everything from scratch in each restaurant. Things are made in a factory and shipped to the stores, similar to how you'd buy a box of Mac and Cheese. Inside they have a packet of \"cheese\" powder. You make Mac and Cheese at home when you open the box and follow the instructions, but that doesn't m... |
What really happens when you swallow something down the "wrong tube"? | [
"Your trachea (windpipe, ie the tube leading to your lungs) branches off your esophagus (food pipe) just below your throat. The opening is covered by a flap called the epiglottis. When breathing, the epiglottis points up allowing air to enter the lungs. When you swallow, it flips down and covers the entrance to th... | [
"> I mean whether you put your left earphone on your right ear or vice versa. I still hear the same thing. Not at all. If you have stereo sound on, and a train is coming from left of your screen to the right, the left earphone will play the sound louder."
] |
Who actually uses the Candela SI unit? | [
"We use it in vision science to describe stimulus or monitor or environment luminance. Usually in cd / m^2 . Many labs have a photometer for this purpose."
] | [
"Too expensive, little or no benefit. The people that benefit from metric (scientists, engineering) already switched over long ago. For everyone else: Does it really matter if the speed limit is in mph or kph? Are you having trouble converting the speed limit to feet per second on a daily basis? No? Then we're fine... |
Has Hacking Proven Password Encryption A Failure? | [
"If someone wants the data badly enough, they will get it; however, that doesn't make it pointless to make it as difficult and as inefficient as possible to get it. Unless this is a very deliberate and targeted attack, people aren't going to waste time on anything but low-hanging fruit. Just like how you lock your ... | [
"I've written some replies on this topic before: * [Preceding the Persian invasion of Greece, what factors prepared them to stave off such an overwhelming threat?](_URL_1_) * [Why wasn't Xerxes more prepared to face the Greeks?](_URL_0_) And in reply to your specific question: * [Why was the invasion of Greece by X... |
Why does the polynomial x^5 - x + 1 = 0 have no exact solution? | [
"There is no *algebraic solution*, so you can only write down or calculate an approximate solution. She states in the video that a solution *exits*, because the the number is defined by the equation, and indeed as you point out the solution is exactly where the graphs of x^4 - 1 and -1/x cross. But you cannot calcu... | [
"Think about things bouncing around. Imagine a box with a fan in it. Put 20 balls in ithe box. Now imagine a basket to one side just the right size for the balls. Turn on the fan. The balls jump around randomly. At some point a ball will fall into the basket. This will happen at a given rate which will depends on h... |
Are there nerves in the umbilical cord? | [
"No. The only structures in the umbilical cord are two arteries and a vein, unsurprisingly called the umbilical arteries and the umbilical vein. The cord's not even made of muscle or skin. It's composed, apart from those blood vessels, of a substance called Wharton's jelly, which is the same kind of stuff that fill... | [
"_URL_0_ They are densely innervated. It is not just keratin and bone. Although the paper does not speak of nociception, they feel pain when they receive an injury to these tissues. If you cut them, do they not bleed."
] |
The shift away from 3D and vividly colored graphics to flatter more geometric designs. | [
"I'm pretty sure there is precedent in psychology that I can find but I think it relates to us wanting to make these things as simple as possible so we don't have to think about it at all. You want a person to use your phone with as little work as possible and then you want them to forget that they used it until th... | [
"_URL_0_ study linked in other link _URL_1_ page 1136 has the key graph world war 1 and 2 had a pretty major impact on getting a generation of americans to keep a clean shaven look forced on them by the military. for this i'm assuming politicians aren't any different from the normal man. interestingly the safet... |
Why do some liquids evaporate faster than others (e.g., rubbing alcohol vs. water)? | [
"Different liquids have different boiling temperature points. Many liquids would start boiling at lower temperatures. Rubbing alcohol has 82.6º C boiling point for example. This means the molecules would gain enough energy at lower temperatures to evaporate (become vapour)."
] | [
"Particals spread out over time (thats why if I sprayed something in one corner, not everyone would smell it at the same time) so over a longer period, the particals move further and further away from the point of origin, and the particals spread thinner and thinner, to the point that you dont notice it anymore."
] |
Meta - Ask John D Sarna anything. | [
"Just to clarify what namer98 told us mods when asking if it was okay to post this: All questions need to be submitted to Professor Sarna **by email** before the AMA. It is not \"live\" like the AMAs we host here in AskHistorians. So, please go to that r/Judaism thread to post your questions **before** the time of ... | [
"Just to warn you, you should limit your question so that it falls within the 20-year rule. We try to stay out of politics, and can't discuss anything that happened after 1996."
] |
Someone told me recently that the UK is the only country to have ever paid off an entire national debt is this true? | [
"Nope, Andrew Jackson paid of the entire national debt in the United States. (Not entire but down to 32,000 dollars which is about 2 million in today's money) Also as your question implies, they paid off the debts of the very expensive napoleonic wars, not necessarily the existing debt."
] | [
"Governments give tax breaks and subsidies to corporations to lure them in to their area. The idea is that bringing that business to the area will, ultimately, bring more business and jobs to the area which, theoretically, will bring jobs to the locals and more tax revenue for the government. Again, theoretically, ... |
Why are there so many religions that evolved from Christianity? | [
"basically, whenever someone had a disagreement with how something should be, they went and started their own branch of Christianity"
] | [
"Mutation + gene duplication + billions of years = amazing things. The part you seem to be asking about is the duplication part. A genome doubles in size by accident, and suddenly you have a lot of room for new evolution."
] |
why is it harder to stop the flow of urine when it's already started than it is before you start peeing? | [
"Your muscles are weak. Look up Kegel exercises. Kegel exercises strengthen the pelvic floor muscles, which support the uterus, bladder, small intestine and rectum. You can do Kegel exercises, also known as pelvic floor muscle training, just about anytime."
] | [
"Imagine a huge crowd of people trying to get into a building with two doors. For them, the doors look identical, but inside the building, one of them leads to a nice, wide corridor, but the other leads into a tight maze. You dont know that one path is much easier than the other, but since the tight path is clogged... |
Why do major cell phone carriers allow companies like MetroPCS, Cricket Wireless, Boost Mobile, etc. to resell their network? | [
"Metro, Cricket, and Boost are owned by T-Mobile, AT & T and Sprint, respectively. So it's basically them selling their networks to people who are more likely to pay cash money for a phone + service. Post paid customers usually pay by debit or credit and sometimes pay their bills after the due date. Meanwhile most ... | [
"Each culture has an 'in' to a particular business in each area. So, one Korean family will come and open a dry cleaning business. When their cousins come, they will tell them the tricks of the trade and the regulations and have the business model set, so their cousins open up another cleaning business one town ove... |
How fresh water fish populations spread from one river network to another without going through (presumably deadly) seawater? | [
"I wondered that about fresh water mussels. So I asked. They have a free living form which basically hitches a ride in the gills of fish. This means the same species can be in one river system even though they are mussels. Similar events can occur for other species. Egrets and other fish eating birds will fly from ... | [
"Imagine you have a computer on your house. Now you want to connect that computer to your friend 100 miles away. How do you do it? You could lay a 100 mile cable, but do you have the permissions to dig up roads and pathways? You would use a company whose cables were already there, and just use that network of cab... |
Baking bread with cosmic rays on the ISS? | [
"cosmic rays transport very little energy, far from the necessary to bake bread in acceptable time frames. what makes it dangerous is its effect on cells and macromolecules, and not directly on macroscopic objects."
] | [
"Exposure to unfiltered sunlight and near-vacuum conditions, most likely. Conducting experiments on site would definitely pose a challenge though."
] |
Like carnivores, do herbivores kill the young of other herbivores to eliminate competition for resources? | [
"At the very least, [prairie dogs muder *alot* of ground squirrels](_URL_0_). I think other murders have been identified since this, but I'm not 100% sure. Remember, absence of evidence is not evidence of absence. Just because we haven't seen it yet, doesn't mean there aren't other herbivores out there that regular... | [
"I wrote a detailed response about Tom Holland's documentary [here](_URL_0_), using primary source to argue that something very similar to modern Islam did exist quite early on. Also worth noting that Crone and Cook's *Hagarism* thesis is not taken seriously anymore (or even at the time) - it literally used only th... |
Why is milk so popular for humans, even though among mammals, milk is only consumed when breastfeeding the young? | [
"There was a genetic mutation about 8,000 years ago that allowed humans to keep consuming milk into adulthood. It made the domestication of dairy cows possible, and made the populations who had the mutation a *lot* more survivable in harsh climates. Later, into modern times, that mutation led to a lot of very delic... | [
"Changed the flair from \"Earth Sciences\" to \"Psychology\". Although φ is not my field, I believe you will find a large part of your answer by researching the concepts of \"imprinting\" and particularly of \"cuteness\" (no, really - it's a thing; at least the way it was defined by Lorenz it is...) and the researc... |
Why putting a spin on things makes them travel straighter (e.g. rifling with bullets) | [
"Most bullets will not be perfectly symmetrical sure to flaws in the manufacturing process. These flaws will cause a bullet to naturally veer during flight. Think of a plane with the tail kinked slightly to one side, it will not fly sight without constant adjustment from the pilot. Since bullets cannot be stress on... | [
"[Here's](_URL_0_) an image of the inclination of the Earth that illustrates the angle of sunlight during the summer solstice in the northern hemisphere. This is the warmest the north pole gets. Now, think about taking a flashlight on a floor. When you point it directly down, the light is concentrated on a small ci... |
Can animal really smell fear or is it a figure of speech? | [
"One of the physiological responses to fear is an increase in sweat. Non-human animals can certainly smell that. Interestingly, so can we, though we might not consciously recognize it as fear. In a [study at Stony Brook University](_URL_0_), waving fear-sweat (obtained by scaring the hell out of people by sending t... | [
"How do you know a year has passed without looking at a calendar? I imagine they sense the temperature/climate changes like anything else."
] |
Muslim Terrorist groups - what's the difference between ISIS, Taliban, Al Qaeda etc? | [
"Taliban - Tribal alliance from Afghanistan. They want control of Afghanistan/Pakistan, as that is the territory they are present in. ISIS/ISIL - Product of the Syrian Civil war, their organization is attempting to create a unified Islamic state throughout the Region they are present in. Al Qaeda - International or... | [
"There are a lot of different schemes for encoding and timing the communications so that don't interfere with each other. [Stolen from this wiki page](_URL_0_): * In the US, AT & T and T-Mobile use GSM which is based on [TDMA](_URL_4_). TDMA tells each phone to transmit in a specific time window. e.g. Phone 1 talks... |
Why does the Fukushima plant still leak so much contaminated water into the sea? | [
"The more important questions are what is your concept of \"so much\"? And does it matter? How much does it matter? [Beta radiation has the weakest penetration power](_URL_0_)."
] | [
"To answer a little more specific from the perspective of a Californian and answering directly about PG & E: They’re simply going to have to pay a fine. Maybe someone higher up in the company gets a sentence. That’s really it. This isn’t the 1st, and it certainly won’t be the last, time that PG & E is responsible ... |
The main differences between Catholicism and Lutheranism | [
"Historically, Lutheranism branched from Catholicism in protest of the sale of indulgences. In the 16th century church, salvation could be acquired by paying cash money for your sins. Luther objected and proposed that salvation was through faith. (Sola Fida) Today's Lutherans don't even exactly match the theology ... | [
"Could you explain what you mean by \"overlooked?\" Who is overlooking the Great Schism?"
] |
Why are cats scared of cucumbers? | [
"It's more the fact that the cat crouches down to eat, then the cucumber is placed behind them without their knowledge. When they turn around they're not expecting it and it shocks them. Another factor is that cats are very picky about where they eat. They just won't eat in an area they think is unsafe or contamin... | [
"Some fruits, when ripening, produce ethylene. Ethylene has a bunch of function in plants, including ripening. So you're using a banana to release ethylene to speed up the ripening of the rest. Not sure the \"dark\" part is relevant, and not all plants are sensitive to ethylene though."
] |
My science teacher said, in physics 5x5=30 but in traditional mathematics 5x5=25. However in physics 5.0x5.0=25. why? | [
"In empirical sciences, there is the idea of significant figures because you're measuring physical objects. A scale or a ruler only is only so precise. The rules for sig figs can be found on the wikipedia page: _URL_1_ 5 has 1 sig fig. 25, however, has two sig figs. Since the input only has 1 sig fig, the product c... | [
"What does it prove? That Jeff Tupper is awesome. What does it achieve? Nothing, by itself. Tupper's formula is strongly related to the concept of a [Quine](_URL_0_ (a program that produces its own source code as output), which is itself strongly related to the concept of [fixed point](_URL_1_ (roughly, a fixed poi... |
Can I develop a visible jawbone through excercise or is it just based on genes during childbirth? | [
"Nothing is determined \"during birth\" your genetics are set at conception. That being said, a \"strong jaw\" is usually tied to testosterone levels during the developing years. Increasing testosterone levels during adulthood may help to define the jaw line slightly, giving a more \"masculine\" look, but It's not ... | [
"You're eating less than you think, and he's eating more than he claims. He probably does minimal exercise at the gym, and downs a couple of sugary gatorades while he's at it. Both of you start a food diary on _URL_0_ (or anything similar), compare after a few days. You'll see what's really up."
] |
When you first start a diet and lose "water weight" that first week, what's really going on? | [
"Carbohydrates exert an 'osmotic' pressure on the water. They retain it. If you have alot of carbohydrates in your tissues then you will have this water weight. When you start dieting, your body uses these carbs in place of your normal food, decreasing the amount of water that is withheld."
] | [
"I'm sorry that I'm no expert, but I remember reading about this the last time a similar question was asked: _URL_0_ Basically, you percieve time faster after your run because of endorphines released during the work out, which means that the music seems slower. This is apparently also why a lot of rock musicians pl... |
Why do sidewalks need to have creases at "equal" lengths, why not one continuous filled in slab? | [
"Sidewalks expand and contract due to moisture and temperature fluctuations; the creases, or scoring, makes the sidewalk crack in certain places, rather than just cracking apart randomly. Looks neater, lasts longer, easier to replace in the event it gets torn up."
] | [
"If all states voted on the same day, that would ensure that the candidates would be campaigning in only the largest states. By spreading it out, more people have an opportunity to see and hear the candidates and (more to the point of the schedule), there's more opportunity for fundraising for the candidates."
] |
Why don't electrons stick to the nucleus? | [
"You'll probably have to start with an ELI5 on Heisenberg's Uncertainty Principle as that's basically the answer. Don't think of protons and electrons as hard little objects - they're not. The electron doesn't *whizz* around the nucleus like the moon round the Earth, it's more a cloud of probability, popping up her... | [
"Stable and long-living particles are harder to find than short-living particles, but stable particles are also less common (we don't see any of them around on Earth apart from the few known stable particles). If they have an electric charge, we can measure them going through the detector. They would typically be h... |
Why don't humans just poop excess fat? | [
"The body saves fat in case it needs the calories later and it doesn't have a cap on how much it saves"
] | [
"We can and do, but it is far too complicated and expensive a process to be practical. _URL_0_"
] |
Are there any full world maps of ancient civilizations' territory? | [
"This was posted the other day. I cannot verify the accuracy of these maps. Some pointed out that the source material is lacking for some of them and that certain divisions are arbitrary, but perhaps this will give you a starting point. _URL_0_"
] | [
"I would crosspost to /r/archaeology, they tend to get this question semi-regularly. Maybe /r/geology for the geological timeframe aspects of the question as well."
] |
According to the Theory of Evolution and the Theory of Plate Tectonics and Continental Drift, how did humans get all throughout the world? | [
"Humans spread throughout the Earth fairly recently on a geologic and evolutionary time-scale. The humans that left Africa were genetically about the same as modern humans, and spread through a world where the continents are in about the same position as they are today. The only differences were from the changing s... | [
"From what I've read they ate a lot more rough course foods. Chewing things that are hard scrape our teeth for us kind of like it does for other animals. The problem for our modern teeth is we eat a lot of soft refined foods and a lot of sugar. That stuff just sits there and gets stuck which causes tooth decay."
] |
What would physically happen to my body if I stopped showering for 6 months? (Besides smelling bad). | [
"Not much. There are people that haven't washed in years or even a lifetime"
] | [
"For example, let's say that you have captured a prisoner of war (POW) from an enemy you're at war with. The POW is your leverage, your way of getting something in return from the other country (could be prisoners of war that they have). You could potentially trade. The POW's have some value as long as they are hig... |
Why do certain businesses refuse to accept certain credit cards as payment, such as Discover Card? | [
"Different cards have different merchant fees. Some businesses don't want to pay, for example, 50c per transaction to discover."
] | [
"Both of these answers are mainly guesses on my part. For the white label players, the networks aren't as focused on the quality of their video players since they aren't as invested in their working correctly. Hulu and Youtube make money by having an easy video streaming service, whereas networks make money by prov... |
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