Split (2)

train · 219k rows

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Do electrons really 'relolve' around the nucleus?	> If an electron exists as an electron cloud, how can it 'revolve' around the nucleus? You've just realized one of the gaping holes in the Bohr model. > Or do they not revolve at all? Not really. They just have certain probability distributions that describe where they're most likely to be. > If so, why do we sa...	[ "A direct relativistic effect is that as the atomic numbers of elements increase, the innermost electrons begin to revolve faster around the nucleus as a result of an increase of electromagnetic attraction between an electron and a nucleus. Similar effects have been found for the outermost s orbitals (and p ones, t...
How were hurricanes tracked in the 17th and 18th centuries?	hurricanes were not 'tracked' in the 17th and 18th centuries. There was little understanding of cyclonic storms and no means of instantaneous communications. A track could be made well after the fact, but that was not 'tracking' in the sense we use the word today.	[ "The List of Atlantic hurricanes in the 17th century encompasses all known and suspected Atlantic tropical cyclones from 1600 to 1699. Although records of every storm that occurred do not survive, the information presented here originated in sufficiently populated coastal communities and ships at sea that survived ...
The question that my professors/teachers have never been able to answer. What's the lowest temperature a flame can have.	You question is nearly impossible to answer because there really isn't a good formal definition of a flame or fire. It's more of an, "I know it when I see it" thing. There are plenty of chemical reactions that give off both heat and light that can occur at low temperatures. If you managed to get a photoluminescent...	[ "Note these are theoretical, not actual, flame temperatures produced by a flame that loses no heat. The closest will be the hottest part of a flame, where the combustion reaction is most efficient. This also assumes complete combustion (e.g. perfectly balanced, non-smokey, usually bluish flame)\n", "In the study ...
what happens after you burst a blood vessel? does the vessel itself reform or do you have a gap there forever?	It's called a bruise. The blood leaks out under your skin and makes a spill. The body patches up the vessel, or seals it off if it's too damaged. Then it cleans up the mess, that's why the bruise turns colors as the crashed blood cells get cleaned up, like after a highway crash. Then you are fine. Other nearby ves...	[ "Blood vessel permeability is increased in inflammation. Damage, due to trauma or spontaneously, may lead to hemorrhage due to mechanical damage to the vessel endothelium. In contrast, occlusion of the blood vessel by atherosclerotic plaque, by an embolised blood clot or a foreign body leads to downstream ischemia ...
Do any non-human animals "remember" things in a way like humans, or only through conditioning? Can an animal "remember" another animal that harmed it? Can an animal plot revenge?	Crows remember shit for years. [here](_URL_0_) Another example is a silverback that, through sign language, described his mother being killed by poachers. He was full grown. [here](_URL_1_) ...now if only my dachshund would remember us saving her when she was a pup next time she has the urge to leave us a "treat" on ...	[ "A study published in 2014 by neuroscientists based at the University of Minnesota suggested that rats are capable of feeling regret about their actions. This emotion had never previously been found in any other mammals apart from humans. Researchers set up situations to induce regret, and rats expressed regret thr...
How much radiation does a single banana give off? How many bananas would it take to kill someone and how long would that process take?	You basically couldn't kill someone by just piling bananas around them. The amount of radiation you need to get someone to kick the bucket is on the order of 2-5 Gy (joules per kg). Even using natural K metal (with a small % of K40), being surrounded by an infinite sphere wouldn't even come near a harmful dose. You'd n...	[ "The radiation exposure from consuming a banana is approximately 1% of the average daily exposure to radiation, which is 100 banana equivalent doses (BED). The maximum permitted radiation leakage for a nuclear power plant is equivalent to 2,500 BED (250 μSv) per year, while a chest CT scan delivers 70,000 BED (7 mS...
how is youtube a sustainable business model? if view count remains constant but video storage costs continue to increase, wouldn't this lead to a permanent loss?	Storage costs are going down exponentially. Every year the cost of storing 1 GB of data is half what it was the previous year. YouTube loses money every time someone uploads a long video that nobody watches, but it doesn't matter because they make insanely high profits off of the top 1% of the most popular videos. A...	[ "In June 2009, \"BusinessWeek\" reported that, according to San Francisco-based IT consulting company RampRate, YouTube was far closer to profitability than previous reports, including the April 2009, projection by investment bank Credit Suisse estimating YouTube would lose as much as $470 million in 2009. RampRate...
does absolutely everyone on the sidelines of an nfl game have a reason to be there?	No. Some people including some family members and celebrities are occasionally allowed on the sidelines. Most of the people there are necessary though.	[ "Residents choose teams around the country to support; David Carter, sports business professor at USC, compared area fans to \"the NFL's version of the United Nations\". Many are from elsewhere in the United States and tend to support teams from their previous cities. 10% of Los Angeles County residents who followe...
facebook scams. what do the accomplish by getting you to share a post?	They are often designed to build up likes and followers then the owners of the page (usually located in a developing country not always though) will sell the page to scammers who can reach a giant audience (iPhone giveaways porn spam snake-oil weight loss solutions etc)	[ "Social networking sites have created issues among getting hired for jobs and losing jobs because of exposing inappropriate content, posting photos of embarrassing situations or posting comments that contain potentially offensive comments (e.g., racist, homophobic or defamatory comments), or even political comments...
how do web browsers work?	When you request _URL_0_, the server sends back a bunch of textual data. Plain text is boring to look at, so a simple markup language was created named html. The browsers job is to parse through the html and display it nicely. Some browsers display things differently than others (that's why many people hate internet...	[ "A web browser is a software application for retrieving, presenting and traversing information resources on the World Wide Web. It further provides for the capture or input of information which may be returned to the presenting system, then stored or processed as necessary. The method of accessing a particular page...
When the United States annexed the former territory of Mexico (California, Utah, Nevada, Arizona, New Mexico, Texas), why were the Spanish names of cities such as Los Angeles and San Francisco retained?	generally speaking, pre-existing towns or settlements weren't renamed, and san francisco is the exception. [according to the 1847 ordinance changing the name of the town,](_URL_0_) "yerba buena" was renamed "san francisco" to prevent confusion. [look, for instance, at this 1839 American map of the US and Mexico-- the...	[ "When the United States acquired the territory comprising Arizona and New Mexico by treaty with Mexico in 1848, those lands not already privately owned, including Spanish and Mexican land grants, nor reserved by treaty for the various Indian tribes, became a part of the \"public domain\" and open under various laws...
Books on U.S.-Native American wars	I quite enjoyed: Jill Lepore, The Name of War: King Philip’s War and the Origins of American Identity (New York: Vintage Books, 1999). It covers one of the earlier conflicts to take place and explores some of the different perspectives and sources on the conflict.	[ "Jacquin published 20 books, including: \"American Indians, The Indian Policy of the United States (1830–1890)\", and \"The American people: origins, immigration, ethnicity\". These are reference books on the history of Native Americans, including the blending of cultures and the initial conquest of the American We...
municipal fiber internet. is it funded by the government or is funded by taxes? or do you just pay for it like you would for any other service (i.e. comcast, xfinity, etc...)? how does a town go about getting it (that is if they are in a state that doesn't ban it)?	As the name suggests Municipal Fiber Internet is provided by the municipality (local government). The organization and funding of this is up to the municipality as is the same for any municipal utility like water, sewage and roads. It is not uncommon for the local taxes to pay for some of it however most strive for the...	[ "By 2013 commercial fiber optics based connections have become commonplace in major city areas usually distributed in house by VDSL2, speeds of 100/10 Mbit/s usually costing about €30/month, and often available by multiple competing ISPs offered in different packaging. More and more rural towns also have fiber avai...
why do salt water and fresh water bodies stay seperate	Land for the most part. Lakes are fed by rainfall, and they occur most often in mountain valleys. Rain falls down the mountainsides making creeks and rivers that feed into the lake, and the water has no where else to go. When rivers feed into the ocean the fresh water mixes and eventually becomes salt water. This i...	[ "The presence of common salt, sodium chloride, helps to preserve salted fish, through inhibition of bacterial growth. When the solution of salt, or brine, is more concentrated—specifically, has a lower water potential—than the fluid of the fish tissue, osmosis will occur. Water molecules will pass from the fish tis...
Im interested in theory of pre-historic advanced civilizations is there any reading material that you could recommend?	Hey there! You're right that it's not a commonly accepted theory, and for good reason. There's no evidence. Most arguments for it are based on "We don't know anything about this era.. So it could be?" This mentality hardly lends itself to any kind of scholarly research, which is based on making conclusions from observ...	[ "In the book \"Did the Gods wear shoes\" the author explored the possible existence of prior civilizations. In his sequel \"They who came before us\" he provides the basis for that possibility. The book focuses on prehistoric mason works around the world. The author uses many detailed pictures along with personal o...
how powerful does a nuclear warhead have to be to destroy our planet?	Planets are pretty big thing and pretty hard to destroy. Even if you somehow managed to shatter a planet to pieces the pieces would just be drawn back to each other to reform a planet unless you pushed the pieces very, very hard away from each other. There is a theory that Earth was impacted by a very large and fast ...	[ "The second, a full-scale nuclear war, could consist of large numbers of nuclear weapons used in an attack aimed at an entire country, including military, economic, and civilian targets. Such an attack would almost certainly destroy the entire economic, social, and military infrastructure of the target nation, and ...
In the Americas, why are Spanish-speaking countries so small and numerous, but there are two enormous English-speaking countries?	After Simon Bolivar drove out the Spanish in South America, he was briefly president of much of Spanish-speaking South America. His vision was for it to be a united country. Other political factions felt differently. Further north, Mexico and Central America were briefly united after independence -- they were all admi...	[ "Spanish is spoken by approximately 35 million people. The United States has the world's fifth largest Spanish-speaking population, outnumbered only by Mexico, Colombia, Spain, and Argentina; other estimates put the United States at over 50 million, second only to Mexico. Throughout the Southwestern United States, ...
why are eggs almost universally sold in packs of 12? what made farmers agree to sell this way?	TLDR; Convenience, 1 shilling = 12 pennies, 1 egg = 1 penny. No need to make change. Under a system that came to be known as English units, which was a combination of old Anglo-Saxon and Roman systems of measurement, eggs were sold by the dozen. It made sense to sell them that way because one egg could be sold for a p...	[ "From the farmer's point of view, eggs used to be practically the same as currency, with general stores buying eggs for a stated price per dozen. Egg production peaks in the early spring, when farm expenses are high and income is low. On many farms, the flock was the most important source of income, though this was...
What's the advantage of having a long lifespan?	Human bodies, especially our brains, take a very long time to develop. We "traded off" our speed of evolution in order to get a more complex body/mind. Part of the reason that huge plants/animals have the longest life spans is so that they don't need as fast of a metabolism to grow to full size. A 1000-kg animal with ...	[ "One prominent and very popular theory states that lifespan can be lengthened by a tight budget for food energy called caloric restriction. Caloric restriction observed in many animals (most notably mice and rats) shows a near doubling of life span from a very limited calorific intake. Support for the theory has be...
Are animals aware of their own shadows and the shadows of other animals and objects?	I think the best comparison would be to a mirror. It answers the same basic question but is more explicit. Most animals cannot recognize themselves in a mirror although there are a few exceptions, mostly birds and primates. About half of all magpies, for example, are able to recognize themselves in the mirror. Interes...	[ "Mimicry and camouflage enable animals to appear to be other than they are. Prey animals may appear as predators, or \"vice versa\"; both predators and prey may be hard to see (crypsis), or may be mistaken for other objects (mimesis). In Batesian mimicry, harmless animals may appear to be distasteful or poisonous. ...
Other than living in a simulation, what other possible implications does this have?	He published an article about this in Physics World, 2010: [Symbols of Power: Adinkras and the Nature of Reality](_URL_0_)	[ "Bostrom argues that \"if\" \"the fraction of all people with our kind of experiences that are living in a simulation is very close to one\", \"then\" it follows that we probably live in a simulation. Some philosophers disagree, proposing that perhaps \"Sims\" do not have conscious experiences the same way that uns...
What role did Persia and Persians play in Greek mythology?	There are no Greek Myths relating to the Persians or Persia directly.	[ "According to Herodotus, the Persians numbered 300,000 and were accompanied by troops from Greek city states that supported the Persian cause (including Macedonia, Thessaly and Thebes). Herodotus admits that no one counted the Greek allies of the Achaemenids, but he guesses that there were about 50,000 of them. Mar...
Could someone explain the differences between and advantages/disadvantages of the different antiseptics? iodine vs alcohol vs peroxide, vs etc?	[Here](_URL_0_) is a well-cited review of several antiseptics, including the ones you mentioned :)	[ "BULLET::::- Iodine is usually used in an alcohol solution (called tincture of iodine) or as Lugol's iodine solution as a pre- and postoperative antiseptic. Some studies do not recommend disinfecting minor wounds with iodine because of concern that it may induce scar tissue formation and increase healing time. Howe...
how does "lottery wheeling" work?	The only part of the Wikipedia article you need to pay attention to says that wheeling does not change the expectation value of the ticket. That means that the probability of paying more for the ticket than you win is still nearly 100% and the more you play, the more you are expected to lose.	[ "Lottery wheeling (also known as lottery system, lottery wheel, lottery wheeling system) is used by individual players and syndicates to distribute a subset of the possible lottery numbers across multiple tickets to ensure that at least one of these tickets will contain a winning combination if several draws are in...
How can I have 80 billion direct ancestors going back to just the 13th Century?	You were made by 2 people, who were made by 4 people, who were made by 8 people... etc. Not including siblings.	[ "In 1994, near the Awash River in Ethiopia, Tim D. White found the then-oldest known human ancestor: 4.4 million-year-old \"Ar. ramidus\". A fossilized almost complete skeleton of a female hominin which he named \"Ardi\", it took nearly 15 years to safely excavate, preserve, and describe the specimen and to prepare...
the difference between public and private sector labor unions	A public sector labor union is a union comprised of government workers. A private sector labor union is a union comprised of private employees. The biggest difference is that public sector labor unions largely negotiate with other government employees or politicians for their contracts. Private sector employees nego...	[ "In the United States, labor relations in the private sector is regulated by the National Labor Relations Act. Public sector labor relations is regulated by the Civil Service Reform Act of 1978 and various pieces of state legislation. In other countries, labor relations might be regulated by law or tradition. \n", ...
given how hard it is to start and run a successful small business nowadays, how were so many immigrants able to come here with nothing, and and still start up businesses in the cities where they settled?	In the old days there were extremely few regulations, and they were not well enforced. If you wanted (for example) to buy some stuff and sell it retail from a wagon on the street, you could just start doing that.	[ "Immigrants have been linked to greater invention and innovation in the US. According to one report, \"immigrants have started more than half (44 of 87) of America's startup companies valued at $1 billion or more and are key members of management or product development teams in over 70 percent (62 of 87) of these c...
How long did it take to create marble sculptures? Weeks, months, or years?	"Months to years, it depends". Many of the famous Renaissance sculptures took between one and three years. Almost three years for Michelangelo's David (september 13th 1501-early spring 1504), about two for Moses, and almost two for the Pietá (1498). Donatello spent more than two years on each of Zuccone, Saint George a...	[ "The accounts of the construction of the Parthenon make it possible to know that the marble intended for the pediments began to be extracted from the quarries of Mount Pentelikon in 439-438 BC.; sculpture work starting the following year. The accounts also show that excavation and transportation expenses were annua...
why do doctors flick syringes before injecting someone? is this just a thing they do in tv shows?	They are checking for air bubbles. Injecting a air bubble into a blood vessel can easily kill a person.	[ "Modern use for syringes goes beyond the doctor’s office, hospitals or medical operating rooms. They have evolved into other industries such as for cooking when injecting liquids for fillers in certain foods. Other uses include printers, for re-filling of the cartridges which are often difficult to perform without ...
the difference between single phase and three phase power	Both are forms of alternating current (AC) Alternating current cycles from +120V to -120V, 60 times per second (assuming you live somewhere that uses 120V 60 Hz for mains power) Single phase power means that all of the power in the wire alternates from +120V to -120V. Three phase power has three wires, all alternat...	[ "Single-phase generator (also known as single-phase alternator) is an alternating current electrical generator that produces a single, continuously alternating voltage. Single-phase generators can be used to generate power in single-phase electric power systems. However, polyphase generators are generally used to d...
can smelling something be unhealthy? like if there's a very bad smell, is there anything dangerous about the act of smelling it?	Yes. Stuff like paint- and glue fumes can be highly toxic. I don't think that "regular" bad smells like rotting fish or excrement are dangerous even in large quantities, but both foster a myriad of harmful microbes so the smell is evolution telling you to stay away.	[ "Phantosmia (olfactory hallucinations), smelling an odor that is not actually there, and parosmia (olfactory illusions), inhaling a real odor but perceiving it as different scent than remembered, are distortions to the sense of smell (olfactory system) that, in most cases, are not caused by anything serious and usu...
My great uncle enrolled in the Charlemagne Waffen SS Division, is there online ressources I could check to find out what happened to him ?	Hi, hopefully someone can drop by to help with something more specific, but you might find these resources helpful : the sub has a wiki for finding military records [here](_URL_0_). You might also try x-posting to /r/genealogy for more tips.	[ "Gottlob Christian Berger (16 July 1896 – 5 January 1975) was a senior German Nazi official who held the rank of \"SS-Obergruppenführer und General der Waffen-SS\" (lieutenant general), and was the chief of the SS Main Office responsible for \"Schutzstaffel\" (SS) recruiting during World War II. Following the war, ...
Feyman diagrams and gauge bosons?	Yes, the axis represents time. Feynman diagrams are not a literal depiction of what’s happening, so the fact that the positron arrow looks like it’s pointing backward in time doesn’t mean that any particle is literally moving backward in time. The gluons are the gauge bosons of the strong force, and the photon is the ...	[ "Gauge theories are important as the successful field theories explaining the dynamics of elementary particles. Quantum electrodynamics is an abelian gauge theory with the symmetry group U(1) and has one gauge field, the electromagnetic four-potential, with the photon being the gauge boson. The Standard Model is a ...
Why is it that high current is dangerous but high voltage (to a certain limit) is not as dangerous?	We can be killed by 0.01A across the heart. An amp is quite a lot really. When you are electrocuted, what kills you is amperage across the heart. Enough amperage and it interferes with the heart's natural electrical signals, stopping it. Voltage and amperage are two different aspects of the same thing. Think of it in...	[ "A high voltage is not necessarily dangerous if it cannot deliver substantial current. The common static electric sparks seen under low-humidity conditions always involve voltage well above 700 V. For example, sparks to car doors in winter can involve voltages as high as 20,000 V. Also, physics demonstration device...
Why do we not perceive the expansion of the universe?	We're not growing larger. Space inside our bodies is expanding, yes, but our cells aren't "anchored" to this space. They're anchored to each other. If you spread your arms wide, your fingertips are continuously moving towards each other at the same rate that new space is appearing within you. Imagine this: Take two l...	[ "The expansion of the universe reaches an infinite degree in finite time, causing expansion to accelerate without bounds. This acceleration necessarily passes the speed of light (since it involves expansion of the universe itself, not particles moving within it), causing more and more objects to leave our observabl...
does a house ever finish settling?	Short answer: no Long answer: I believe it is never settled because it's the materials of the house expanding due to the heat of the day and then contracting when it's cooling down at night	[ "The old house, dating from the Revolutionary War-era, turns out to be structurally unsound and has to be torn down before the previous owner's $6,000 mortgage is paid off. The Blandingses hire architect Henry Simms (Reginald Denny) to design and supervise the construction of the new home for $18,000 ($187,000 in 2...
in the shell sort algorithm, why are the numbers 1,4,10,23,57,132,301,701,1750 used? they seem to be ambiguous and are really confusing me...	Shell sort partitions the data. The exact partition is not that important, but the properties of the partition (i.e. "gap sequence") do affect the runtime. "Gonnet and Baeza-Yates observed that Shellsort makes the fewest comparisons on average when the ratios of successive gaps are roughly equal to 2.2." You need to...	[ "Shellsort is a generalization of insertion sort that allows the exchange of items that are far apart. The idea is to arrange the list of elements so that, starting anywhere, considering every \"h\"th element gives a sorted list. Such a list is said to be \"h\"-sorted. Equivalently, it can be thought of as \"h\" in...
Why are British colonies in the Caribbean so homophobic?	I feel this is a loaded question as Montserrat, the Cayman Islands, the British Virgin Islands and the Turks and Caicos Islands all consider homosexual activity perfectly legal. So perhaps the question should more focus on why Jamaica itself is so homophobic as being a British Colony past or present seems to not be a v...	[ "All other colonials not already resident in the UK or the Crown Dependencies lost the rights of abode and work in the UK when the Act went into force. This caused anger in the affected colonies as the Act, which resulted from the desire to prevent ethnic-Chinese people in Hong Kong with UK and Colonies Citizenship...
Why is angular momentum one-sided even if a spinning object is symmetrical?	It is convention only, to allow scientists to talk to each other without having to describe which coordinate system they are using every time. Let me explain. The direction of the angular momentum of an object doesn't mean anything by itself. What matters is that when object A with angular momentum interacts with obj...	[ "Like linear momentum, angular momentum is vector quantity, and its conservation implies that the direction of the spin axis tends to remain unchanged. For this reason, the spinning top remains upright whereas a stationary one falls over immediately.\n", "If two or more axes have the same direction, the axis with...
why does scanning take so long if photocopying or taking a photo of something is so quick?	Because you have a cheap scanner. Cheap scanners are slow. Expensive high end scanners are very fast.	[ "The scanning techniques are generally slower in acquiring images, due to the scanning process. As a result, efforts are being made to greatly improve the scanning rate. Like all scanning techniques, the embedding of spatial information into a time sequence opens the door to uncertainties in metrology, say of later...
why do heroin users have to switch veins? what does the heroin do to “kill” the vein?	It's not the heroin. It's poking the same spot with a needle over and over again without giving it enough time to heal. It can get more complicated where if you do give it time to heal after you've abused it too much it will develop scar tissue which makes it harder to inject there.	[ "After injecting herself with heroin using a syringe, the user will extract approximately 5 ccs of blood from her vein, which another user will inject into her vein. It is unclear if there is enough heroin in the small volume of injected blood to get high or if the high that many users claim is a result of traces o...
how are things n% water?	Heat it until the water evaporates, check its mass before and after and calculate the percentage	[ "Parts-per notation is often used describing dilute solutions in chemistry, for instance, the relative abundance of dissolved minerals or pollutants in water. The quantity “1 ppm” can be used for a mass fraction if a water-borne pollutant is present at one-millionth of a gram per gram of sample solution. When worki...
Why do shadows "kiss"?	This is because the sun is an "extended" light source, as opposed to a point light source. Because of this, there is an area called the [penumbra](_URL_1_), where the shadowing object creates a partial shadow. When two penumbras meet, it makes the "kissing" darker shadow. See also [Shadow Blister Effect](_URL_0_)	[ "Rather than depicting death as a winged angel the sculptor instead chose a skeleton. The eroticism of the kiss is hard to escape - the sculpture shows youth welcoming death as a partner. The sculpture is at once romantic and horrifying, which leads to the varying views of the people that view it. It attracts and r...
how usa is one of top polluters in most sources but is consistently ranked relatively favorably (in the middle) for how polluted it is?	A lot of it is just how big the US is and how much the population and industrial centers are spread out. If I have a country that is 100 square miles and pollutes x amount, and a country that is 1000 square miles and pollutes 5x amount, the second country pollutes 5 times as much as the first country but said pollutio...	[ "According to the WHO, India has14 out of the 15 most polluted cities in the world in terms of PM 2.5 concentrations. Other Indian cities that registered very high levels of PM2.5 pollutants are Delhi, Patna, Agra, Muzzaffarpur, Srinagar, Gurgaon, Jaipur, Patiala and Jodhpur, followed by Ali Subah Al-Salem in Kuwai...
the waco siege.	a ups driver was delivering packages to the compound and one broke open showing weapons, inert grenades and black powder. UPS reported this to the sheriff who contacted the ATF. This info along with reports of automatic fire from the compound led to sucspision that the Brach Davidians were illegally modifying weapons...	[ "The Waco siege was the siege of a compound belonging to the religious sect Branch Davidians, carried out by American federal and Texas state law enforcement, as well as the U.S. military, between February 28 and April 19, 1993. The Branch Davidians were led by David Koresh and were headquartered at Mount Carmel Ce...
Napoleonic Era and Uniforms (Nit-Picky Questions)	So, there's a million questions. It would be beneficial if you reworded your question for a single question and ask a few over a few days.	[ "In 1828, the greyish-blue trousers worn during the later stages of the Napoleonic Wars were replaced by dark blue \"Oxford mixture\" trousers for winter wear. White duck trousers were worn in summer until 1845. Although the fantastic profusion of gold and silver lace on officers' uniforms was checked, decorations ...
what is the evolutionary benefit to a species, such as the praying mantis, to have the female kill the male after copulation?	By eating the male, the female gains a lot of nutrients, which will enable her to have healthier and stronger offspring. In this way, there is a higher chance that the genes of both the male and the female are carried on.	[ "Copulation in a monogynous male is a sacrificial system. They not only cause genital damage to themselves but in many cases die during copulation spontaneously such as \"Argiope aurantia\" or are cannibalized by the female. This can be observed in many spider species such as the red back spider which consumes the ...
if someone is on death row and has a medical issue causing them the die sooner than their execution date, why would they be given medical help?	Up until the moment the executioner turns the key, the state must provide care for their convicted felons. The logic behind this is that up until that last moment, the execution is not 100% certain. There are years of appeals, and the governor might still pardon the convicted at the last moment. Also, allowing someo...	[ "Physicians can cause a patient's death \"actively\" (for example, by administering a fatal drug) or \"passively\" (by withholding food, water, or medical care that would prolong life). This option may be offered to patients who are terminally ill and are severely disabled or in great pain with no hope of recovery....
it's common knowledge that exercising regularly and pushing yourself is good for your health and heart, but how does that logic work that the harder you work your heart, the healthier it becomes, instead of wearing it out?	The human body is a fascinating thing. It has been developed to be able to adapt to different lifestyles. When working out, you are essentially telling your body that for your lifestyle, you require stronger muscles. The body has learned to oblige to this, thus makes muscles stronger by adding more protein to the muscl...	[ "Physical health is also something that needs to be worked on daily, whether it is exercise, healthy eating, or relaxation. states that blood pressure, heart rate, and respiration rate will all decrease when one is relaxed. This means that a person's heart does not beat as fast and their breathing is shallow, helpi...
How much variety is there between single celled organisms? Would two of my red blood cells be completely identical down to the smallest measure?	Two different questions really. Red blood cells aren't organisms. 1) Vast. 2) Potentially, but unlikely	[ "All white blood cells are nucleated, which distinguishes them from the anucleated red blood cells and platelets. Types of leukocytes can be classified in standard ways. Two pairs of broadest categories classify them either by structure (granulocytes or agranulocytes) or by cell lineage (myeloid cells or lymphoid c...
Sickle Cell Anemia and UVR / Melanin Evolution Correlation?	It is because the sickle cell hemoglobin gene when it is heterozygous (meaning only one copy of one of your chromosomes and the other chromosome has a normal hemoglobin) protects against malaria. Since malaria is much more prevalent in tropical locations and so is darker skin, the sickle cell trait is selected for by e...	[ "The most important genetic alteration associated with poor prognosis in uveal melanoma is inactivation of BAP1, which most often occurs through mutation of one allele and subsequent loss of an entire copy of chromosome 3 (monosomy 3) to unmask the mutant copy. Because of this function in inactivation of BAP1, mono...
why is it that when my battery dies on my iphone it takes 10 minutes to turn back on while connected to a charger?	Apple makes sure that the phone is charged to a minimum % (3%-5%?) before it turns on, to make sure it doesn't die again when you unplug it.	[ "If a battery has been completely discharged (e.g. the car lights were left on overnight) and next is given a fast charge for only a few minutes, then during the short charging time it develops only a charge near the interface. The battery voltage may rise to be close to the charger voltage so that the charging cur...
What is happening during the onset, peak and duration of a local anesthetic?	Local anesthetics, like lidocaine, work by stabilizing the membrane of cells. What this means is that they reversibly decrease the rate of depolarization and repolarization of excitable membranes. One such type of membrane is the cell membrane of pain-sensing neurons. By blocking the ability of the nerve membrane to de...	[ "Induction of anesthesia is facilitated by diffusion of an inhaled anesthetic drug into the brain and spinal cord. Diffusion throughout the body proceeds until the drug's partial pressure within the various tissues is equivalent to the partial pressure of the drug within the lungs. Healthcare providers can control ...
why does ukip have so many meps as opposed to other government positions?	UKIP supporters really, really, really hate the EU. Most everyone else just doesn't care about MEPs. So UKIP voters are more energized in European elections than the general public.	[ "UKIP had 24 MEPs elected at the 2014 European elections, which was its highest tally to date. By the time of the 2019 elections, it had three MEPs following multiple defections. It won no seats in those elections and there are now no UKIP MEPs in the European Parliament.\n", "In the 2009–14 parliament, UKIP rank...
- why is, what seems like rape so prevalent in the animal kingdom?	Because most animals don't have morals. Humanity has gotten to a point of intelligence and society that we don't need to allow ourselves to just procreate willy-nilly. Cats, dogs, and other animals rape as part of procreation because they don't have the morals, the intelligence, the sense of caring for others, that s...	[ "It has been noted that behavior resembling rape in humans is observed in the animal kingdom, including ducks and geese, bottlenose dolphins, and chimpanzees. Indeed, in orangutans, close human relatives, copulations of this nature may account for up to half of all observed matings. Such behaviors, referred to as '...
why don't vending machines keep their change topped up from the money people put in?	Filtering a coin box and setting it up so that it can provide change is possible, but requires a more expensive model of vending machine. Most vendors are willing to pay for a cheaper model because guess what, people are still going to use it.	[ "Vendors have a wide variety of machines to choose from. The selection of a machine is important because it can affect sales, time spent servicing the machine, willingness of locations to allow placement of the machine, and a variety of other factors affecting overall profits. Like a car, once a vending machine is ...
What did ancient teenagers do for fun?	You mean a 'really' ancient civilisation such as the Greeks or the Egyptians, or will a more recent example do? Roman teenagers from the 17th/18th/early-19th centuries grew up in the street and the society they lived in was rife with violence. Every rione (ward) of the city usually had a long-standing rivalry with a...	[ "In Ancient Iran, youths under 24 years of age received thorough training in the sport of their time which included miming, horsemanship, polo, dart throwing, wrestling, boxing, archery, and fencing. They were taught under conditions of severe hardship so that when the need arose they could endure the adverse condi...
why do egg-whites foam when we whisk them and do not when there is just a very tiny amount of egg yolk in it?	The foam form the whites is formed by proteins from the protein-rich egg-white. The yolk contains fats that destroy the protein foam (also called an emulsion). You can try this by mixing in a tiny amount of cooking oil into the egg-whites: it will have the same lack-of-foam effect as a tiny amount of yolk.	[ "The physical stress of beating egg whites can create a foam. Two types of physical stress are caused by beating them with a whisk, the first of which occurs as the whisk drags the liquid through itself, creating a force that unfolds the protein molecules. This process is called denaturation. The second stress come...
how do we not run out of telephone numbers?	How did you get that figure? Did you do 10 factorial or something? Isn't it as simple as 10^10? Edit: you did do 10!, that's for a combination of things that exclude what's already been used and can't be used again. So a line of x amount of people has x! Combinations, you can use it that way because there can't be ...	[ "This is the process whereby a telephone subscriber whose telephone line is maintained by one company, usually a former monopoly provider (e.g. BT), can choose to have some of their calls automatically routed across a different telephone company's network (e.g. Talk Talk) without needing to enter a special code or ...
What memorials/monuments, if any, has the USA donated to other countries that is not about the US in anyway.	I think that the Marshall Plan was a pretty swell thing for the U.S. to do. It's not a commemorative statue, but you could probably find a list of many public projects that were completed as a result of the money. Almost all of the money was given in the form of grants and European countries, to my knowledge, were only...	[ "American War Memorials Overseas (AWMO) was founded in 2008 and is a non-profit corporation working to document, promote, and preserve non-government supported War Memorials honoring Americans outside of the United States. American War Memorials Overseas is a 501(c)(3) nonprofit corporation and as such is entirely ...
What exactly was the Battle of Actium?	Not to discourage any further answers but while you wait you'll probably enjoy these older posts: [What was Mark Antony's intention when he gave Rome's lands to Egypt in 34BC? And why did it take Rome two years to start a war against him?](_URL_6_) [What were some of the rumors about Cleopatra during the civil war be...	[ "The Battle of Actium was the decisive confrontation of the Final War of the Roman Republic, a naval engagement between Octavian and the combined forces of Mark Antony and Cleopatra on 2 September 31 BC, on the Ionian Sea near the promontory of Actium, in the Roman province of Epirus Vetus in Greece. Octavian's fle...
seeing as video/picture quality is constantly increasing (1080p, 4k etc..), is there a limit to the quality that the human eye can notice a difference?	Theres alot of conversation about this actually... You really need to focus on DPI, since 1080p is very different on a 20" tv vs an 80". But then it matters how far away it is, and how good your vision is... Some would say we already eclipsed that limit with 1080p tvs at normal viewing distances. Yet... its trivial...	[ "However, in any situation where standard-definition video cameras are used, the quality is going to be poor because the maximum pixel resolution of the image chips in most of these devices is 320,000 pixels (analogue quality is measured in TV lines but the results are the same); they generally capture horizontal a...
how do studios get to film in places as dense as new york without interrupting business and traffic, while also not being interrupted during filming?	I've got 10+ years working in the industry, my father was a camera operator and my grandfather was a Director/Producer of stage, TV and Film. The studio, via the production coordinator/manager, makes an agreement with the city, and they provide Police assistance to close down the area the crew wants to film in. Someti...	[ "While filming on busy New York City streets presents countless challenges, the unit has, over the years, developed a strong working relationship with the film industry. The unit makes an effort to ensure that New York City remains a popular location for filming.\n", "The New York City Transit Authority denied pe...
why do large amounts of flammable material in a small space explode (ex: gasoline can) when ignited instead of just lighting on fire and burning like wood	Burning causes things to expand, heat up and release gases. if its in an enclosed space such as a pipe, grenade casing, gas can, etc... then the pressure from these reactions builds up causing the big bada boom.	[ "When this mixture of fuel and air is ignited, especially in a confined space such as a warehouse or silo, a significant increase in pressure is created, often more than sufficient to demolish the structure. Even materials that are traditionally thought of as nonflammable (such as aluminum), or slow burning (such a...
warm fronts	Warm air moves to an area where there is already cold air. As the warm air moves into the new area, it gets pushed up on top of the cold air. Unlike cold fronts, the weather at warm fronts tends to be stable. In other words, as the warm air rises and cools, it becomes dense enough that it's not going to continue risi...	[ "A warm front is a density discontinuity located at the leading edge of a homogeneous warm air mass, and is typically located on the equator-facing edge of an isotherm gradient. Warm fronts lie within broader troughs of low pressure than cold fronts, and move more slowly than the cold fronts which usually follow be...
How did Einstein 'discover' time-dilation?	It was pretty well established by then that light acts like a wave. Now any other wave that we know about needs a medium to propagate through: ocean waves need water, sound waves need air. It was natural to assume that light needed a medium too, which they called the 'ether', but every experimental attempt to prove it...	[ "Einstein subsequently (1907) suggested an experiment based on the measurement of the relative frequencies of light perceived as arriving from a light source in motion with respect to the observer, and he calculated the additional Doppler shift due to time dilation. This effect was later called \"transverse Doppler...
why does a weak am/fm radio signal result in a consistent static/fuzzy sound while a weak satellite radio signal results in intermittent high quality sound?	The simple answer is that AM/FM is an analog signal, which you can "kind of" pick up. Think of analog as a scale of 100-0 with the quality increasing or decreasing as you move from the transmitter. Satellite radio is a digital signal. Think 1 or 0. It's either there, or it's not. The same holds true for satellite TV, ...	[ "Reception of RF signals is sensitive to the size of obstruction in the path between the transmitter and the receiver. Generally speaking, if the size exceeds the wavelength the reception is interrupted. Since the wavelength is inversely proportional to frequency, it follows than that the higher frequency broadcast...
why are anarchists and nihilists put on the same political wing as socialist and communists?	If you look at it economically, anarchism has strong ties to socialist/communist theory. Anarchists are pretty misunderstood, it's not all about no rules and complete chaos. Early anarchists believed that you should grow food, and whatever extra you had you should give to your neighbours for free, and vice versa. Th...	[ "Some forms of anarcho-communism such as insurrectionary anarchism are strongly influenced by egoism and radical individualism, believing anarcho-communism is the best social system for the realisation of individual freedom. Hence, most anarcho-communists view anarcho-communism itself as a way of reconciling the op...
How long does it take for plant cells to grow?	This varies greatly from plant to plant, and it will vary based on the conditions. You also need to define 'grow' because cells can expand or divide to grow. Plants that perform C4 photosynthesis (like grasses) tend to expand and divide rapidly under the right conditions, while plants that perform CAM photosynthesis ...	[ "Growing cells require synthesis of new nucleotides, membranes and protein components. These materials can be obtained from carbon metabolism (e.g. glucose metabolism) or from peripheral metabolism. The enhanced flux observed in abnormally growing cells is brought about by high glucose uptake.\n", "Plants grow fr...
How thin is the surface of a bubble?	Short Answer: Somewhere around 50-500 nano meters, depending on where you measure the bubble's thickness. Long Answer: This can be measured using a very clever natural phenomenon, [thin-flim interference](_URL_0_). So a bubble has two sides, the outside and the inside. Light coming from the sun hits the outside laye...	[ "A 1 mm bubble has negligible extra pressure. Yet when the diameter is ~3 µm, the bubble has an extra atmosphere inside than outside. When the bubble is only several hundred nanometers, the pressure inside can be several atmospheres. One should bear in mind that the surface tension in the numerator can be much smal...
Did Romans really have those feathered things on top of their helmets? If so, why?	The "feathered thing" is called a crest and its usage depends on the time period: In the days of the early republic, it was not common. During the late republic (post 3rd century B.C.) it was very common among legionaries. After the reforms by Augustus, only centurions were wearing crests. In the later empire, they...	[ "The origin of these very elaborate helmets is uncertain but appears not to have been Rome. Various origins have been suggested, including a theory that they came from Rome's eastern provinces. They were produced from the early 1st century AD through to the mid-3rd century. Although they are relatively light, they ...
how is something scientifically proven to be a fact?	Scientists don't tend to use the word "fact" for any generalized statement. I dropped a ball from the top of a 100-meter building and I measured that it took 4.9 seconds to reach the ground. That's a fact. It's evidence consistent with the theory objects on Earth fall with an acceleration of approximately 9.8 meters...	[ "In science, a \"fact\" is a repeatable careful observation or measurement (by experimentation or other means), also called empirical evidence. Facts are central to building scientific theories. Various forms of observation and measurement lead to fundamental questions about the scientific method, and the scope and...
feces being a major source of harmful germs,how is it the lower intestine isn't chronically infected.	The vast majority of the bacteria in your colon are (mostly) harmless organisms that have evolved to live with us. The high populations of these bacteria tend to suppress the growth of other, harmful bacteria. Think of an apartment building with 100 units. 98 of them are already occupied by quiet residents. Even if...	[ "An infarcted or dead intestinal segment is a serious medical problem because of the fact that intestines contain non-sterile contents within the lumen. Although the fecal content and high bacterial loads of the intestine are normally safely contained, progressive ischemia causes tissue breakdown and inevitably lea...
What led to Sulla's retirement after being declared dictator for life?	The sources are particularly lousy for this: the wretched Appian on the one hand, and on the other Plutarch, more interested in the morbid details of his wasting disease than any politics. Scullard and Keaveney both argued that Sulla simply got tired and decided that he'd done enough to ensure a return to Republican f...	[ "In 79 BC, Sulla resigned his dictatorship, re-established consular government and, after serving as consul in 80 BC, retired to private life. In a manner that the historian Suetonius thought arrogant, Julius Caesar would later mock Sulla for resigning the Dictatorship—\"Sulla did not know his political ABC's\". He...
what are ghz and what do they mean when it comes to computer specs?	Hz is a measure of frequency- the number of times something happens per second. If something has a frequency of 3GHz, it means that it happens three billion times per second. In the case of computers, that's the speed of its internal clock. A single operation in a computer can take multiple steps, and the clock speed...	[ "BULLET::::- On August 31, 2011, in Austin, Texas, AMD achieved a Guinness World Record for the \"Highest frequency of a computer processor\": 8.429 GHz. The company ran an 8-core FX-8150 processor with only one active module (two cores), and cooled with liquid helium. The previous record was 8.308 GHz, with an Int...
Do rockets use fossil fuels? Is there danger of running out of rocket fuel as we deplete oil reserves in the next 50-200 years? If so, are there alternative fuels that have the necessary power to take us into space?	We are in no danger of running out of liquid oxygen or liquid hydrogen, as they can be extracted from water. You can make a workable rocket with just those fuels, although a big fat first stage full of low density hydrogen has penalties. Realistically, if absolute supply of kerosene or methane is an issue, we'll be t...	[ "energy). In chemical rockets, unburned fuel or oxidizer represents the loss of chemical potential energy, which reduces the specific energy. However, most rockets run fuel-rich mixtures, which result in lower theoretical exhaust velocities.\n", "Since solid-fuel rockets can remain in storage for a long time with...
when a hard drive sets aside space for a download, what is it filled with before it actually receives the data that takes up the space?	Logically, the filesystem is told to reserve the physical space for the new file. Physically, the space of a hard drive that are reserved still contain whatever data was last in that space.	[ "When data is deleted from storage devices, the references to the data are removed from the directory structure. The space can then be used, or overwritten, with data from other files or computer functions. The deleted data itself is not immediately removed from the physical drive and often exists as a number of di...
subjective vs. objective	Subjective is a judgement or experience. Objective is a reliably reproducible measurement. Both can be scientific. A good example is flavor versus chemistry. A cherry is tangy, sweet. That's a subjective statement because everyone experiences flavor in a different way, but it's still important to science to characteri...	[ "Some have argued that the distinction between objective and subjective assessments is neither useful nor accurate because, in reality, there is no such thing as \"objective\" assessment. In fact, all assessments are created with inherent biases built into decisions about relevant subject matter and content, as wel...
Do we have any concept of "infinite" I terms of time and space?	_URL_0_ > We now know (as of 2013) that the universe is flat with only a 0.4% margin of error. This suggests that the Universe is infinite in extent; [...] All we can truly conclude is that the Universe is much larger than the volume we can directly observe. _URL_1_ > The size of the Universe is unknown; it may ...	[ "Aristotle also distinguished \"things infinite in respect of divisibility\" (such as a unit of space that can be mentally divided into ever smaller units while remaining spatially the same) from things (or distances) that are infinite in extension (\"with respect to their extremities\").\n", "The basic premise p...
how does trade between countries work in terms of currency? if country a buys millions of dollars worth of commodities from country b, how do they pay? do they give them cash? gold? bank transfer?	Think of countries as regular companies for this case. Countries don't really buy things - it's state companies that are run (more or less) like private companies, think of train networks requiring trains, power grids require generators, water networks needing pumps, etc. - when they buy something - and it doesn't ma...	[ "By an accounting identity, Country A's NCO is always equal to A's Net Exports, because the value of net exports is equal to the amount of capital spent abroad (i.e. outflow) for goods that are imported in A. It is also equal to the net amount of A's currency traded in the foreign exchange market over that time per...
counterfeit vs fake vs forgery for items	A forgery usually refers to a specific item, like a signature or an original painting. If you were two see two identical copies of the same original painting, you could conclude that forgery has occurred merely from the fact that there are two of them. You still might need an expert to tell which one is the forgery, ...	[ "Sometimes, forgery is the method of choice in defrauding a bank. There are three main types of cheque forgery: (a) Counterfeit. This is a cheque that has been created on non-bank paper to look genuine. It relates to a genuine account. (b) Forged signature. The cheque is genuine, but the signature is not that of th...
How do you defend the purpose of Medieval History?	I don't actually feel as if I need to defend medieval history for its social relevance - the fact that I enjoy studying it is really enough for me. It should be obvious that medieval history presents special problems of understanding, in particular in relation to the number of sources, and I have always liked grappling...	[ "Medieval period oriented living history groups and reenactors focus on recreating civilian or military life in period of the Middle Ages. It is very popular in Eastern Europe. The goal of the reenactor and their group is to portray an accurate interpretation of a person who credibly could exist at a specific place...
why do we still need sunscreen? why haven't we as humans adapted to the heat of the sun after all this time?	> Why haven't we as humans adapted to the heat of the sun after all this time? It's not the heat that's the problem. It's ultraviolet light, which damages cells and can lead to skin cancer. And we have adapted. Tanning is our body's response to excess sunlight, and it helps reduce (but does not eliminate) sun-...	[ "Sunlight has been shown to be beneficial in some skin conditions and enables the body to make vitamin D, but with the increased awareness of skin cancer, wearing of sunscreen is now part of the culture. Sun exposure prompts the body to produce nitric oxide that helps support the cardiovascular system and the feelg...
Why does water turn yellow when electric current passes through it for some time?	It's a physical reaction, not chemical, the electricity is causing it not an interaction of chemicals. Ions (atoms missing bits) come off the anode (positive side). If you leave wires connected to a battery in water for long enough you'll see one of them will eventually disintegrate. That's why you see metal for out...	[ "Water attenuates light due to absorption which varies as a function of frequency. In other words, as light passes through a greater distance of water color is selectively absorbed by the water. Color absorption is also affected by turbidity of the water and dissolved material.\n", "BULLET::::- Pure water is near...
if i keep the calories down but it's all mtn dew & chocolate & chips, will i lose weight or stay fat from all the sugar?	If you eat fewer calories than you use, you lose weight. If all those calories come from soda, chocolate, and chips, you lose other things. Like muscle mass, hair, and vital signs.	[ "While you don't need to limit the sugars found naturally in whole, unprocessed foods like fresh fruit, eating too much added sugar found in many processed foods can increase your risk for heart disease, obesity, cavities and Type 2 diabetes. The American Heart Association recommends women limit added sugars to no ...
Let's be honest: Is interstellar/intergallactic space travel possible at all?	You are pretty much correct in your analysis. Long-term generation ships using nuclear pulse propulsion (or similar) could perhaps reach another star, but that technology is too far away to even say how far away it is.	[ "Intergalactic travel is hypothetical manned or unmanned travel between galaxies. Due to the enormous distances between our own galaxy the Milky Way and even its closest neighbors—hundreds of thousands to millions of light-years—any such venture would be far more technologically demanding than even interstellar tra...
If we never see objects fall into black holes due to time dilation, how do black holes gain mass?	It's a somewhat tricky question, actually. From the point of view of the infalling particle, time doesn't slow down at all as it approaches the horizon; in fact, it doesn't feel anything special at the horizon at all, and it continues to fall in as normal. To the outside, however, it's true that infalling matter appe...	[ "As predicted by general relativity, the presence of a mass deforms spacetime in such a way that the paths taken by particles bend towards the mass. At the event horizon of a black hole, this deformation becomes so strong that there are no paths that lead away from the black hole.\n", "To a distant observer, cloc...
why does traveling to new places generally make people happy?	1. Humans have an instinctive desire to explore. Following our instincts feels good. 2. It distracts us from our usual daily concerns, which aren't visible there. 3. We don't have so many chores or work to do when on vacation.	[ "The new travelers have traveled the world, they have seen the classic sites. Staying at a Western hotel is not attractive enough, and they are excited by the prospect of experiencing the authentic local way of life: to go fishing with a local fisherman, to eat the fish with his family, to sleep in a typical villag...
how the conversion rates between currencies are decided. who, or what, decides these?	It works kind of like the stock market. Look up forex trading for details. But basically a bunch of people make and take offers to trade one currency for another, and the rates those people are willing to trade at determine the exchange rate.	[ "Convertibility of a currency determines the ability of an individual, corporation or government to convert its local currency to another currency or vice versa with or without central bank/government intervention. Based on the above restrictions or free and readily conversion features, currencies are classified as...
how does alka-seltzer work?	Stomach acid isn't there to break down your food, its primary role is to destroy bacteria in anything you just ate. The enzymes in your small intestine are responsible for most of the digestion. Heartburn is caused by stomach acid finding its way up, and out of your stomach where it attacks the lining of your esophag...	[ "It was developed by head chemist Maurice Treneer. Alka-Seltzer is marketed for relief of minor aches, pains, inflammation, fever, headache, heartburn, stomachache, indigestion, acid reflux and hangovers, while neutralizing excess stomach acid. It was launched in 1931.\n", "Alka-Seltzer is an effervescent antacid...
how does the opening bottle of wine in a shoe work?	Liquids don't compress. Holding the bottle upside down and striking the heel sends shockwaves through the bottle, which terminate in the spongey cork, causing it to move. Since it can't move into the liquids, it moves out of the neck.	[ "Wine bottle openers are required to open wine bottles that are stoppered with a cork. They are slowly being supplanted by the screwcap closure. There are many different inceptions of the wine bottle opener ranging from the simple corkscrew, the screwpull lever, to complicated carbon dioxide driven openers. The mos...
Why are many diseases that are potentially lethal to animals harmless to humans (and vice versa)?	A couple points: 1) yes, the tree of life contains a wide spectrum of immune systems. The innate immune system (macrophages, granulocytes e.g. neutrophils, complement proteins, etc) varies across the animal clade. The adaptive immune system (T and B lymphocytes and the lymphoid organs) also become increasingly complex...	[ "Susceptible animals include cattle, water buffalo, sheep, goats, pigs, antelope, deer, and bison. It has also been known to infect hedgehogs and elephants; llamas and alpacas may develop mild symptoms, but are resistant to the disease and do not pass it on to others of the same species. In laboratory experiments, ...
How can exoplanets in systems whose planes do not allow transits visible to earth be detected?	There's a lot more methods to detect exoplanets. I'll summarize them : 1. Transit Photometry as you said. This detects only a tiny fraction of the exoplanets since you need aligned systems there could be tens of thousands of planets not seen because of misalignment. However this is the most successful technique right...	[ "The transit method of discovering exoplanets relies upon carefully monitoring the brightness of a star. If a planet is present and crosses the line of sight between Earth and the star, the star will dim at a regular interval by an amount that depends upon the radius of the transiting planet. In order to measure th...
Why do we as humans often times feel he need to feed wild animals such as birds and fish when we get nothing in return?	Bear with me on this: When our ancestors moved down from the trees and started to live in social groups out in the open this put selective pressure towards developing altruistic behavior. Some evolutionary biologists such as Robert Trivers argue that in humans this altruistic system is regulated by emotional dispositi...	[ "It is common for animals (even those like hummingbirds that have high energy needs) to forage for food until satiated, and then spend most of their time doing nothing, or at least nothing in particular. They seek to \"satisfice\" their needs rather than obtaining an optimal diet or habitat. Even diurnal animals, w...
Can animals really predict disaster ahead?	The seizure sniffing dogs are a legit thing. They're a form of service animal that are very highly trained. I saw one assisting his "owner" (for lack of a better word in this context). About a minute before the guy started to seize, the dog did something (I didn't notice the signal, but apparently the guy did) to ...	[ "For centuries there have been anecdotal accounts of anomalous animal behavior preceding and associated with earthquakes. In cases where animals display unusual behavior some tens of seconds prior to a quake, it has been suggested they are responding to the P-wave. These travel through the ground about twice as fas...
What is the correlation between decibels and sound waves?	I believe your confusion comes from thinking of decibels as being units used to measure sound waves. They aren't. The units typically used to measure sound waves are either micropascals RMS (for amplitude/pressure) or watts/meter^2 (for intensity). Decibels are, in general, just a convenient way to represent *ratios...	[ "Sound is measured based on the amplitude and frequency of a sound wave. Amplitude measures how forceful the wave is. The energy in a sound wave is measured in decibels (dB), the measure of loudness, or intensity of a sound; this measurement describes the amplitude of a sound wave. Decibels (dB) are expressed in a ...
Why does a wood stove burn more vigorously when the door is slightly ajar than when fully open?	It's air pressure. When the stove is completely open, air pressure is roughly equalized so oxygen being burned is immediately replenished. When the door is only slightly open, the fire is using up the oxygen in the oven causing an area of low pressure, so the atmosphere outside of the oven "rushes in" to attempt to equ...	[ "The wood is very dense and produces a hot flame when burned, which functions as an excellent source of heat for barbecues and wood-burning stoves. However, the wood is not desirable for wood fireplaces because the heat causes popping, thereby increasing the risk of house fires.\n", "The system is more efficient ...
Did any ancient civilisation ever actually build the kinds of complex mechanical puzzles you see in popular fiction like Indiana Jones, Tomb Raider, Uncharted, National Treasure etc?	Hi, you may be interested in a couple of posts from [the FAQ](_URL_2_): * [Were the tombs of South American civilizations the booby-trapped nightmare we see in entertainment?](_URL_1_) - South & amp; Central America, Egypt * [Many fantasy/historical computer games and RPGs feature "dungeons", ie a large labyrinthian...	[ "The oldest known mechanical puzzle also comes from Greece and appeared in the 3rd century BCE. The game consisted of a square divided into 14 parts, and the aim was to create different shapes from these pieces. In Iran \"puzzle-locks\" were made as early as the 17th century (AD).\n", "Eblong likened the game's p...
What can we make using the 6 elements in the /r/askscience logo?	Pretty much none. Neon is a noble gas which won't form compounds with much and definitely not with all of these at any reasonable energy. You might be able to squeeze everything but Ne onto some long molecule all as substituted atoms, but even that would be a stretch. The only compound that sticks out containing two...	[ "The company takes its name from scandium, the 21st element of the periodic table, alloys of which are used to make golf clubs and fishing rods. Element 21 claims that their use of scandium improves performance compared with that of other commonly used metals.\n", "The symbols of chemical elements are evenly spac...
When 'unlikely' animals tolerate the company of each other, what is happening at a psychological level?	A polite reminder. This is AskScience. No layman speculation, no guessing, no anecdotes, no jokes. Please check the sidebar if you're unsure whether your answer should be here or not.	[ "In real life situations, animals (including humans) have to cope with stresses generated within their own species, during their interactions with conspecifics, especially due to recurrent struggles over the control of limited resources, mates and social positions (Bjorkqvist, 2001; Rohde, 2001; Allen & Badcock, 20...

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