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November 2

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Technocracy

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What country or countries today would be considered most like a technocracy? The article mentions China and Russia in passing, but I find that frankly ridiculous. 59.46.38.107 (talk) 00:54, 2 November 2010 (UTC)[reply]

This was my question. I forgot to sign in. The Masked Booby (talk) 00:56, 2 November 2010 (UTC)[reply]
Our article references this source for the Russia/China claim: The Technocratic Trend and Its Implication in China from Observa. I would hardly call that a notable or widely-read, well-respected expert publication in the domain(s) of technology, politics, or social commentary; so take the citation with a grain of salt. I think there are no current "technocracy governments", though there are elements of technocracy in many states and non-state actors (particularly, certain corporations and business structures). Nimur (talk) 00:59, 2 November 2010 (UTC)[reply]
I agree with the summation. Now would you care to hazard a guess at which may be considered more technocratic than the norm? The Masked Booby (talk) 01:04, 2 November 2010 (UTC)[reply]
To be fair I think this may be more a question for the Humanities reference desk. --jjron (talk) 01:58, 2 November 2010 (UTC)[reply]
It might be more useful to compare, more generally, the way that expert decisions are made in different states. For example, in the United States, when you have a complicated scientific question that has to do with policy — say, concerns about global warming, or whether the US national labs can guarantee the reliability of its nuclear stockpile without testing, or whether GMO crops should be regulated differently than non-GMO crops — there are bodies that policymakers can consult for guidance (like the National Academy of Science, or the JASON group), and there are agencies that often have some regulatory role over those areas (e.g. EPA or DOE or FDA in the examples given). But in practice the question of regulatory authority and of which brand of technical expertise to go to often devolves into Congressional debates, since they control the purse strings and can pass the laws. So we get a particularly adversarial way of making technical decisions — instead of "what do the scientists say," it becomes, "what does my scientist say vs. what your scientist says." It would be hard to argue for this reason that there is much "rule by experts" in the United States — on anything even slightly controversial, experts become proxies for other political decisions.
We might compare this to, say, France. When the French government wants to make a technical decision, it picks a few experts it trusts, asks them what to do, and does it. It doesn't open it up to public discussion most of the time, and it doesn't usually enter into the arena of party politics. (There are exceptions, I am sure.) This is one of the reasons that the French did not have anything like the American experience when it came to picking a nuclear waste repository, for example. It's experts said, "bury it here, this way," and that was that. In the United States, after some 50 years of trying to come up with such a plan, we find it endlessly scuttled by local and national politics, which deploy the experts in whatever way suits them best.
I don't know the situation in China or Russia but my inclination is to think the Chinese use experts more like France and less like the United States. None of these countries are really "technocracies" in the standard sense, but they have pretty different roles for experts in the public domain. There is a lot of work in the field of Science and technology studies that is concerned with looking at this question. --Mr.98 (talk) 02:03, 2 November 2010 (UTC)[reply]
For what it's worth both China and France are often described in the media as having decisions made by "Technocrats", as does the EU, and formely communist russia (I think that description is less commonly used for modern russia). Please use google to verify rather than asking me.
Nevertheless none of these are true "technocracies" - decisions are still heavily informed by political matters (eg france) - perhaps China is the best example of a near technocracy. I think that the perception is mostly due to bias - all modern goverments use technical experts to make decisions. (Do 'anglo-saxon' counties tend to be more heavily influence by NIMBY concerns? maybe so [1]) Sf5xeplus (talk) 06:03, 2 November 2010 (UTC)[reply]
I don't think it's really a NIMBY issue so much as it is an expectations of public participation issue. Everybody's NIMBY if you ask them if they want something big and toxic in their backyard. The trick about France and China is they don't ask them and people on the whole don't expect to be asked. In the US (and to a lesser extent in the UK), the form of deliberative government that has grown up there really sits on the idea that you always ask people what to do, which leads to the kinds of political and regulatory environments we are talking about. Germany is something of a separate case, if I recall. This table in a book that compares the US, UK, and German (and I also think Japanese and French) approaches to regulating biotechnology describes sort of the kind of analysis I am talking about. There are very different political "styles" in the countries we are talking about in respect to how they make expert decisions, and that leads to a lot of the difference in results that we see between them. I agree that none of them are "technocracies" in the strict definition, which I don't think has ever really existed. But some ways of using expert opinion are more "technocratic" than others. --Mr.98 (talk) 13:26, 2 November 2010 (UTC)[reply]
Some countries like to give themselves the appearance of being a technocracy; Romania's Elena Ceauşescu liked to pretend that she was a world renowned chemist, despite leaving school with good grades in needlework followed by a brief job in a textile factory lab. Alansplodge (talk) 10:15, 2 November 2010 (UTC)[reply]
Which country has the highest number of Nobel prizes per capita? Which country has made the most life-changing inventions and discoveries? Its the UK, of course. 92.29.115.229 (talk) 12:24, 2 November 2010 (UTC)[reply]
Of your one factual statement and one opinion with a ton of unstated and unsourced assumptions, the former is not even true. According to data on the relevant WP pages (here and here), UK nobels-per-capita looks like 1/530K vs Switzerland at 1/300K and Sweden 1/335K. Those are just two of the only four I bothered to check (US is 1/952K and Germany 1/802K), so there may be others as well. Remember verifiability is a core wikipedia policy. DMacks (talk) 12:40, 2 November 2010 (UTC)[reply]
I don't see a technocracy valuing a Nobel prize in literature or peace though, so you might want to consider that into your equation. Googlemeister (talk) 13:12, 2 November 2010 (UTC)[reply]
I don't see Nobel Prizes having anything to do with technocracy. They have largely to do with where research is fostered, and it is totally unwarranted to assume that they would be more fostered in a technocracy than not. --Mr.98 (talk) 13:29, 2 November 2010 (UTC)[reply]
Sorry should have typed England rather than the UK. 92.28.243.168 (talk) 15:38, 2 November 2010 (UTC)[reply]
I don't see how that helps much... According to Demography of England the population is 49,138,831 in 2001 or according to Demography of the United Kingdom England's population 50,762,900 from a 2006 estimate. DMacks didn't give the number of Nobel prize winners for the UK and I'm lazy to work it out for myself but as the population of the UK is 58,789,194 in 2001 or 60,587,300 from the 2006 estimate we can guess the number of winners they estimated is probably 111 or 114 or perhaps 115 to be generous. So even if we assume all these winners are from England and we take the later figure yet use the 2001 population we still only end up with ~1/427k which is still less then Switzerland and Sweden. May be you're going to limit yourself to those living in certain areas in England now but can you at least ensure you have better then 1/300K this time? (We haven't of course established that is the highest nor does it make sense to start limiting to arbitary areas in one place but not the others but anyway...). Edit: Actually looking more closely at DMacks answer the UK number of winners is source to an article and is indeed 115 so lucky that I used that. Nil Einne (talk) 03:23, 3 November 2010 (UTC)[reply]
Third in the world is not bad and I expect that if only the science-related Nobel prizes are included then it would be higher. Not forgetting all the famous English scientists. The Industrial Revolution was born in England, and was a kind of technocracy. 92.29.117.88 (talk) 11:15, 3 November 2010 (UTC)[reply]
Not bad? You first claimed the UK was the best when this was proven to be wrong you then changed this to England, you now simply say it is 'not bad'. As for your second claim, Switzerland (with 20) is at 1/389k if we remove economics, literature and peace prize winners, Sweden (with 14) at 1/671k and England (with 84) at 1/617k so it seems that England may beat Sweden but they still get their arse whipped by Switzerland. (I used a population of 51809700 a mid 2009 estimate for England [2] since Switzerland and Sweden are 2009 and 2010 estimates respectively.) Further we haven't established that all 84 really belong to England nor have established they aren't any higher that haven't been considered. Nil Einne (talk) 08:40, 4 November 2010 (UTC)[reply]
Ignoring all the ad hominum stuff, the roll of famous scientists and being the birth-place of the industrial revolution overrules the lesser consideration of only being 2nd or 3rd place in the Nobel prize league. So the UK, Britain, or England is the most technocratic country. 92.29.115.158 (talk) 10:54, 4 November 2010 (UTC)[reply]
It used to be widely understood that an English gentleman doesn't stoop to vulgar boasting. O tempora o mores! Alansplodge (talk) 23:12, 4 November 2010 (UTC)[reply]
No boasting intended, just answering the question asked, with the supporting reasons. 92.15.28.27 (talk) 14:50, 6 November 2010 (UTC)[reply]

Clothes drying under clothes pegs

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When I hang my clothes out to dry on a clothes line why is that the fabric underneath the pegs gets dry just as quickly as the rest of the cloth? Wouldn't it seem logical that that small patch covered by the peg would remain damp? (I can guess at the type of answer I would give here, but am interested to hear what others think). --jjron (talk) 03:24, 2 November 2010 (UTC)[reply]

No, because it's such a small amount. HalfShadow 03:26, 2 November 2010 (UTC)[reply]
Gravity helps. If you hang a long-sleeved shirt out to dry, the top will be dry far sooner than the bottom of the arms and waist. The Masked Booby (talk) 03:27, 2 November 2010 (UTC)[reply]
As the cloth near the pin dries, the water under the pin diffuses into the dry area. Ariel. (talk) 07:31, 2 November 2010 (UTC)[reply]
And, at least in my experience, in many cases the assumption is wrong. The part under the pegs does dry slower that equivalent areas not under them. But the effect is small, and the overall amount of water is so small that usually nobody cares. --Stephan Schulz (talk) 07:37, 2 November 2010 (UTC)[reply]

laminated wood

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whats laminated wood

example

http://www.youtube.com/watch?v=pvZXqSn-mIs&feature=mfu_in_order&playnext=1&videos=H6X28Y6mdrU —Preceding unsigned comment added by Kj650 (talkcontribs) 05:03, 2 November 2010 (UTC)[reply]

Laminated wood is pieces of wood glued together to make a bigger single piece. When the pieces are very thin and flat we call this Plywood.
In the video the pieces (look closely at the end grain of the wood in the video) are about 1" thick - you should be able to see that 3 pieces - the grain of the wood doesn't match so there are 2 joins.
A very thing flat piece of wood on top of something else is also a wood laminate and is called a veneer
Usually the pieces of wood are joined longways, when they are joined longways, and shortways it's called Glued laminated timber Sf5xeplus (talk) 05:22, 2 November 2010 (UTC)[reply]

train deaths

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The following discussion is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.


does anybody think this

http://www.dreamindemon.com/2010/02/22/three-teen-girls-unable-to-outrun-train-struck-and-killed/

was likely a suicide like this

http://www.dreamindemon.com/2010/02/27/police-two-teen-girls-hit-by-train-were-part-of-suicide-pact/


and the guy was lying so he didnt get committed —Preceding unsigned comment added by Kj650 (talkcontribs) 05:34, 2 November 2010 (UTC)[reply]

Please see the disclaimer at the top of the page The reference desk does not answer requests for opinions. Sorry.Sf5xeplus (talk) 05:40, 2 November 2010 (UTC)[reply]
The discussion above is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.

Faster than Light

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Lets assume i hold a lamp, and i travell in perfect vaccum at the the speed of ½c, will not the light from the lamp move faster then c? Daily motion of the Heavens was to hard to understand? But the moon goes around the earth, the earth goes around the sun, and the sun goes around the milky way, doesn't a light from the moon get a push, or is c independant to the course of the satellites of the universe? —Preceding unsigned comment added by 92.254.188.129 (talk) 12:36, 2 November 2010 (UTC)[reply]

The light will move away from the lamp at the speed of light, and this is what you (travelling with the lamp) will observe. An outside observer will also see the light moving away from you at the speed of light. This is one of the fundamental postulates of Einstein's Special relativity. The Michelson–Morley experiment is a famous early (failed) experiment roughly along the lines of the concept you are suggesting. --jjron (talk) 13:56, 2 November 2010 (UTC)[reply]
Basically the answer is that everyone will measure the speed of light (in a vacuum) as being c, no matter how fast they or the light emitter is traveling. It's extremely counterintuitive but has been verified by experiment pretty thoroughly. It is, as Jjron notes, the foundation of Special Relativity — SR is basically an exploration and elaboration of the implications from this fact. --Mr.98 (talk) 14:41, 2 November 2010 (UTC)[reply]
Would the light be red-shifted or blue-shifted to the .5c speed observer? Googlemeister (talk) 16:26, 2 November 2010 (UTC)[reply]
Neither, but it would be red-shifted to someone "stationary" behind him and blue-shifted to someone "stationary" in front. --Sean 16:40, 2 November 2010 (UTC)[reply]

92.254.188.129, If light were a classical wave in the sense of being a vibration in an elastic medium, then the answer to your question would be 'no'. The light would always have a fixed speed relative to that medium, and if a light source were moving in that medium in the direction of propagation of the light, the speed of light relative to the source would actually be c-v, where v is the speed of the source relative to the medium. In order for an observer to observe light at a speed equal to c+v, they would have to either move into the light beam or else move with a light source which is moving backwards relative to the direction of propagation.

However, in recent times, the official belief is that light propagates in empty space and that it defies the normal rules of vector addition of velocities. Einstein postulated words to the extent that light will always be measured to have the speed c irrespective of the motion of the source or the receiver. This postulate is the cornerstone of the special theory of relativity. And so, based on either 20th century physics, or 19th century physics, the answer to your question is 'no'. You cannot push a light beam faster by pushing the source. Such a vector addition phenomenon is something which applies to particle projectiles and not to waves. David Tombe (talk) 22:44, 2 November 2010 (UTC)[reply]

Is the odd fact of both observers seeing the light go at the same speed explained by time going at different speeds for each of them?
Well the second is defined in terms of the speed of light (or rather, frequency of radiation from the caesium 133 atom), so time must be the same for both observers in their own rest-frame, but each observes time as going slower in the other's reference frame. Dbfirs 17:31, 3 November 2010 (UTC)[reply]

The anon asks about 'the odd fact of both observers seeing the light go at the same speed'. This 'odd fact', which is widely acknowledged to be counter-intuitive because it defies classical Galilean addition of velocities, is a postulate which is the cornerstone of a theory. But I have never seen any attempt to explain this 'odd fact' in its own right. At any rate, one should never get any of this confused with the issue of units of measurement. The theory is independent of units of measurement. David Tombe (talk) 17:27, 4 November 2010 (UTC)[reply]

I've corrected my indent error to make clear that I was replying to the (unsigned) supplementary question. The way that we define a unit of measurement determines what we mean by that measurement, and thus whether it "goes at different speeds". Only in General relativity is "time" (as measured by this definition) different for observers in different gravitational fields. I can't get my brain around any alternative way to define time. Perhaps there isn't a logical alternative. Dbfirs 23:02, 4 November 2010 (UTC)[reply]

Well I'm afraid that we'll have to disagree on that. The system of units decides the numerical value of a speed, but it doesn't determine the speed itself as a physical concept. David Tombe (talk) 10:21, 5 November 2010 (UTC)[reply]

Yes, obviously the system of units is irrelevant, but the way we define a measurement determines what we mean by it. Time is not easy to define in an abstract way. Dbfirs 07:45, 6 November 2010 (UTC)[reply]
If you as an observer move faster than light, you will experience something similar to the sound barrier but visually. Everything ahead of you will be visible but nothing behind you is. ~AH1(TCU) 18:40, 7 November 2010 (UTC)[reply]

Cheaper to turn off Compact fluorescent lamps briefly?

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With old fashioned incandescant lightbulbs the consensus view was that it was cheaper to leave them on rather than turn them off for a few minutes, as the stress of being turned on or off wore them out more quickly. What is the best strategy regarding energy-saving lightbulbs in a domestic situation? Thanks. 92.29.115.229 (talk) 12:45, 2 November 2010 (UTC)[reply]

It depends on the CFL. Some ballasts are more gentle, some less. But in general, CFLs are designed with a limit on the number of expected switches. That said, mine now seem to come with warranties of 10 or even 12 years, so the much greater financial risk seems to be losing the warranty slip. The design limit is large enough that manual (as opposed to, say, movement-triggered) switching is unlikely to be a problem. --Stephan Schulz (talk) 12:55, 2 November 2010 (UTC)[reply]
In the UK they are often given away, or are available for a few pence each. 92.29.115.229 (talk) 13:06, 2 November 2010 (UTC)[reply]
It's an interesting scenario. Given that CFLs typically use 20-30% the energy of an incandescent bulb for the same light output and are considerably more expensive to buy, it would seem to make a lot more sense to turn off the incandescent to save power and money as they're costing lots to run but are cheap to replace. Older CFLs had a warm up period where they started a bit dull and gradually brightened to full intensity, and as far as I know they still do, so that makes turning them on and off inefficient in terms of having a consistent light output. In Australia incandescent bulbs are being phased out and I was reading recently of people complaining that their new CFLs were having short lifespans, shorter they were claiming than their old incandescents (I believe it was generally the cheaper brands and seemed to be worse in certain locations). The reason suggested was that power fluctuations were causing high wear on the CFLs leading to the short lifespan. If correct, this would suggest they are quite susceptible to wear and tear and the answer to your question would be to leave them on. --jjron (talk) 13:27, 2 November 2010 (UTC)[reply]
List_of_MythBusters_episodes#2006_season, Episode 69. shoy (reactions) 15:43, 2 November 2010 (UTC)[reply]
Better link: MythBusters (2006 season)#Lights On/Off. --Anonymous, 07:27 UTC, November 3, 2010.
I think this myth started in the days when fluorescent lamps were very expensive and electricity was very cheap. (Yes, I can remember them.) The claim had a better chance of being true then, but it was probably just a marketing lie even in the "old days". From a psychological viewpoint, the flickering and reduced light output for the first second or two after switchon might be a valid reason for leaving the light on rather than turning it off for a few minutes, but warm-up time is shorter if the lamp is still warm from recent use. Dbfirs 08:25, 3 November 2010 (UTC)[reply]
If you are leaving a room for fifteen minutes or longer, it makes sense to turn off a fluorescent light. For a shorter time away, leave the light on. If you pay time of day rates, at peak rates the time may be five minutes. These times take into account the cost of replacing the lamp if it burns out soon due to frequent turning on and off. From a pure energy cost basis, they could be switched off if you will be away only a few seconds. This is per US Department of Energy. I have to pay for light bulbs, unlike some above who somehow get them "free." As Robert Heinlein pointed out "There ain't no such thing as a free lunch." The manufacturers do not produce them free, so it is likely your tax dollars paying for them. If it is in an overhead fixture, there is also the risk and inconvenience of getting a ladder and changing them, or paying a janitor to change them in a commercial building. Compact fluorescent bulbs have a drastically reduced life if they are turned on and off frequently. The stated lifetimes on a package of GE fluorescents assume they will last several years if they are burned for several hours per day. General electric says that compact fluorescents "work best if they are left on for over 15 minutes each time they are turned on" and that they "take up to 3 minutes to warm-up. Frequently switching them on and off will shorten the life of the product." Edison (talk) 14:18, 3 November 2010 (UTC)[reply]
That sounds excellent advice, though the timing will depend on the cost of replacing the fitting. The UK "free" and "10p in supermarkets" compact fluorescent bulbs are subsidised by the electricity companies who have to show that they have encouraged energy conservation. Dbfirs 17:14, 3 November 2010 (UTC)[reply]
I was just in a US store, and regular GE CFLs sell for several dollars apiece. A government might subsidize the cost to encourage a shift away from incandescents, but once incandescents are banned, it would be odd for them to go on subsidizing the CFLs, in contrast to other useful items which went unsubsidized. One might want to stock up on them while they are still free/cheap, but do they have some limited shelf life before capacitors, etc, go bad? Likewise, one might stock up on very cheap incandescent bulbs before their manufacture is phased out. I think the latter can be stored indefinitely and still work fine. Edison (talk) 21:06, 3 November 2010 (UTC)[reply]
I would stock up on too many. LED lights are getting cheaper and brighter all time although they do still suffer heat problems particularly in enclosed fixtures and don't always have the longevity that's sometimes claimed. Nil Einne (talk) 20:02, 4 November 2010 (UTC)[reply]
I've already stocked up on cheap incandescent and CFL bulbs, but am wondering if I have been foolish because I've just installed my first LED sytem. With current outputs, I find both LED and CFL light less pleasant than the old incandescent lamps. I assume Nil Einne meant "wouldn't" above. Dbfirs 23:11, 4 November 2010 (UTC)[reply]

If man evolved from monkey, why are there still monkeys?

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It might seem like a trivial question. We also evolved from bacteria, but they are still here. However, if the evolution was ape > primitive man (like the Austrolopitecus) > us, why did the middle species disappeared? Theoretically, the cave men should be better adapted than the original apes, shouldn't they then be here among us? Quest09 (talk) —Preceding undated comment added 13:10, 2 November 2010 (UTC).[reply]

Simply because of the competition for the living space. Man and chimps separated, and used a different territory (men like the savanna better, chimps likes the forest better), and therefore they never eliminated each other. Well, that is until very recently, where we started to trim the tropical forest for our own use, which is killing the few thousands of chimps remaining.
However the intermediates (that you call cave men) either used the same type as territory as Man (savanna) or the same type as apes (tropical forest) and therefore had a hard time to compete against either. They could have won the competition, of course, and eliminated us, but it just happen that they didn't, we and apes were better adapted to survive in our own type of territory, it seems. --Lgriot (talk) 13:37, 2 November 2010 (UTC)[reply]
Sometimes, monkeys have attacked humans on their own territory. (http://news.bbc.co.uk/2/hi/1107970.stm)
(Incidentally, monkeys are not chimpanzees.) -- Wavelength (talk) 20:02, 2 November 2010 (UTC)[reply]
This is a classic question for which the internet has many nice succinct answers: [3]. Short story: chimps actually do occupy a different niche than man, and practically all of the middle species that occupied the same niche have disappeared. (Consider all of the extinct species in Genus Homo.) --Mr.98 (talk) 13:41, 2 November 2010 (UTC)[reply]
e/c No. Organisms evolve to become better adapted to their current environment, but that does not mean they are 'better' than the organism they evolved from. Have a read also of Common descent, Evidence of common descent, and Human evolution as starting points. And for proof of concept, using a thought experiment, try living in the jungle with some chimpanzees/gorillas/orang-utans, etc to determine which species is better adapted to that environment. --jjron (talk) 13:44, 2 November 2010 (UTC)[reply]
Remember the same argument could be made for bacteria. Why do single celled organisms still live if multicelled ones are better adapted? The simple answer as above answer have stated is better adapted doesn't mean better in every way. Organisms can co-exist if they fill different niches. Humans may be better adapted to live in some environments and conditions but in different ones other organisms are better adapted. (Given all our tech we can now comfortably live in many environments partly by changing our environment to suit us but it took us a while to get here.) If you're talking about such extreme comparisons as bacteria vs humans, humans can't live in another humans mouth or stomach, many bacteria can. Speciation is somewhat relevant here and to some extent so is Species problem. Nil Einne (talk) 13:59, 2 November 2010 (UTC)[reply]
The most fundamental explanation, it seems to me, is that humans did not evolve from modern monkeys. Humans and monkeys both evolved from the same common ancestor, which is now extinct. The same goes for bacteria. Humans did not evolve from modern bacteria—rather, modern bacteria and humans are both descendants of a now-extinct common ancestor. —Bkell (talk) 14:08, 2 November 2010 (UTC)[reply]
Mankind did not evolve from any modern-day apes. Both chimps and humans share a common, now-extinct, ancestor. Probably Nakalipithecus or something very similar to it.
However, even if Nakalipithecus was still around, it wouldn't be a logical paradox. It's not as if every single one of them magically turned into either a chimp or a human. Populations probably got separated from the main group and began adapting to their new surroundings. Eventually they adapted so much that they were no longer the same species as the group they got separated from. If, hypothetically speaking, some of them had found some sort of isolated monkey-paradise, it's would not have been impossible that they would have remained mostly unchanged over all this time while other members of their species adapted and evolved. It's too bad that didn't happen, I'll bet biologists would love to get a blood sample from one. APL (talk) 14:34, 2 November 2010 (UTC)[reply]
Apart from the actual substance of this question, humans are generally not considered to have evolved from Monkeys, but rather Apes (in fact, humans are considered a Great ape). The trouble is, apes are more closely related to Old World monkeys than Old World monkeys are to New World monkeys, making a good illustration of the inconsistencies in the traditional way in which we classify life. Buddy431 (talk) 15:10, 2 November 2010 (UTC)[reply]
If we are the progeny of our grandparents, why do we have cousins? The answer is blindingly obvious: we are not the progeny of our cousins; we both evolved from common ancestors; and our existence does not invalidate the existence of our cousins. They share many traits with us, but have many different traits than us. As we pursue more distant ancestral relations, we see fewer common traits; and if we keep investigating farther up the ancestral tree, we gradually and eventually reach an ancestor who is quite unlike ourselves. If we count all the offspring of a very distant ancestor, we will clearly see a very broad group of individuals. Nimur (talk) 16:16, 2 November 2010 (UTC)[reply]
Are you replying to me, Nimur, or to the original question? You're answer doesn't make much sense as a reply to my earlier remark. Buddy431 (talk) 18:53, 2 November 2010 (UTC)[reply]
(I was responding to the OP. Sorry for indent-confusion; I hope I have fixed it. Nimur (talk) 19:19, 2 November 2010 (UTC)[reply]
As explained |here. CS Miller (talk) 16:47, 2 November 2010 (UTC)[reply]
I don't understand why any answer has involved information or theory or any other knowledge -- the question itself contains a logical absurdity and so needs nothing but logic to answer it. (The OP needs to ask a question that makes sense to get an answer that isn't just logic-based.) Look: "if the evolution was ape > primitive man (like the Austrolopitecus) > us, why did the middle species disappeared? Theoretically, the cave men should be better adapted than the original apes, shouldn't they then be here among us?" But the evolution was also "something else" then "ape" (or whatever); and it was "something else earlier" then "something else" then "ape"; and so on. The question asks why "the middle species disappeared," but objectively there is no "middle species," which is entirely an invention of the words used by the OP, and literally doesn't exist otherwise. The question implies that every single ancestor of every single species should still exist, EXCEPT the first. The obvious answer to this is: look around -- the premise of your question is clearly untrue. As for "why?", then you're asking "Why does ANYTHING go extinct?" I'm sure the OP can look up "extinction" and quickly come up with better comprehensive answers than we will provide here. But "why didn't the middle species survive" is literally a senseless question, apart from the general question of "Why doesn't EVERYTHING survive, except the first ancestor?" 63.17.94.75 (talk) 04:21, 4 November 2010 (UTC)[reply]

The answer to this question is that evolution works by divergence. Some organism XO exists in locations A and B. Over large quantities of time XO adapts to location A in one way and to location B in another way, producing separate species XA and XB. XO will only continue to exists if there's some location C where no adaptation is necessary. This happens more frequently in the oceans (e.g. the continued existence of more primitive sharks or things like coelacanths) because ocean regionally tend to show less long-term variability than land regions. Our primitive intermediary ancestors no longer exist because either (a) they diverged as a group until they became us, or (b) they diverged as a separate group in different directions (e.g. neanderthal man) were either reabsorbed into our group or died out as the environments they were adapted to disappeared.

The idea is only confusing when you think of the human race as a necessary outcome. When you think of it more like a river, which can split and lead off into different directions (where some forks dry up completely and only one fork leads to where we are) it's a bit clearer. --Ludwigs2 05:00, 4 November 2010 (UTC)[reply]

Plant respiration

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Photosynthesis requires intake of Carbon dioxide and the plants release oxygen in the process. However, do plants breathe oxygen like animals? --117.204.87.227 (talk) 16:18, 2 November 2010 (UTC)[reply]

Yes. They use carbon dioxide with water to make glucose. At night, plants burn this glucose by taking in oxygen. However, plants give off more oxygen than they take because to grow they need to join glucose together to make cellulose, so not all of the glucose is burned up. --The High Fin Sperm Whale 16:25, 2 November 2010 (UTC)[reply]
Plants certainly take in oxygen for respiration, but "breathe" isn't really the word to use to describe it. --86.130.152.0 (talk) 16:57, 2 November 2010 (UTC)[reply]
Yeah, the term breathing usually refers to respiration via lungs, which plants of course don't have. Something I just learned that surprised me is that plants respire not only through their leaves, but also through their roots; see soil gas. Our root article does mention "breathing pores" in reference to aerating roots, so apparently the word "breathing" is at least occasionally used when discussing plant respiration. Red Act (talk) 19:02, 2 November 2010 (UTC)[reply]
Cooler than that, is this paper which discusses how Equisetum telmateia aerates its roots by taking air in through its leaves, allowing it to grow in waterlogged soil, which is about as close to breathing as a plant will get. The paper predicts that in the extinct Calamites from the Carboniferous, up to 70 litres of air could have been transported to its roots per minute! SmartSE (talk) 20:38, 2 November 2010 (UTC)[reply]
Just to clear up a common misunderstanding. Many people believe plants photosynthesise during the day and respire only at night. However plants undergo cellular respiration all the time, both day and night, just like animals. --jjron (talk) 14:07, 3 November 2010 (UTC)[reply]

Where are all the universes ?

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I have read the Many-worlds interpretation article, but there is something I can't understand, no doubt due to my limited knowledge of physics. If there are many universes beyond our own, where are they ? Do they exist in the same sense that our universe exists, i.e. physically ? Wouldn't so many universes need a humungous amount of spacetime to contain them ? I guess I would intuitively think that Mother Nature would use her resources more sparingly. Regards, 62.241.87.223 (talk) 17:04, 2 November 2010 (UTC)[reply]

"Beyond our own universe" means just that i.e. not having a location anywhere in this universe, and posessing each its own spacetime. On the presumption that there are infinitely many of them, encompassing every option of every alternative, there is someone very much like you wondering the same thing. The many-worlds theory is not proven but here are ideas in fiction about it. Cuddlyable3 (talk) 18:30, 2 November 2010 (UTC)[reply]
These scientist will eventually figure out that the "universes" that they see in the formulas are just representations of other galaxies that have been completely separated by the emptiness of space. —Preceding unsigned comment added by 165.212.189.187 (talk) 18:26, 2 November 2010 (UTC)[reply]
This is certainly not what the MWI is about, at all. --Mr.98 (talk) 18:28, 2 November 2010 (UTC)[reply]
Agree. 165.212.189.187's interpretation is completely incorrect and is unsupported by any reliable scientific literature. Here is one of the foundational papers of many-worlds interpretation, Quantum Mechanics and Reality (1970). The field has absolutely no connection to extragalactic astronomy. Nimur (talk) 18:53, 2 November 2010 (UTC)[reply]
Sure and thats precisely how all the multiverse perpetuators want to keep it. Except extragalactic astronomy is part of our universe, helps us form theories about multiverse, and its relationship to the mulitverse is inseperable. —Preceding unsigned comment added by 165.212.189.187 (talk) 20:22, 2 November 2010 (UTC)[reply]
No, I think you are just fundamentally confused on this. MWI is completely incompatible with the idea that the other universes are just galaxies separated by long distances, sorry. --Mr.98 (talk) 00:05, 3 November 2010 (UTC)[reply]
See Multiverse for some discussion of this. Short answer: nobody is really sure. They might just be somewhere parallel to us in 3D space (what you mean by "physically" existing, I think), or they might be in some sort of weird quantum space, or something like that. In general this is one of those quantum things that once you've heard it ten times, you say, "oh yes, multiple universes, sure sure," but when you really try to make sense of what it would mean intuitively (e.g. not just with some equations), it becomes pretty clear that it falls outside of everyday human concepts and makes very little sense. That's a limitation of our brains, not to the concept. (I don't know whether the concept makes sense or not — I'm no physicist. But there are lots of quantum things that similarly make very little intuitive sense, yet appear pretty clearly true.)
There is no reason to think that Mother Nature would be conservative with quantum things. It's not a good metaphor to use in this situation, if it ever is good. --Mr.98 (talk) 18:28, 2 November 2010 (UTC)[reply]

Other universes would obviously be outside this one, potentially with different rules. Unless someone developes a inter-universe traveling device, we'll probably never know. scientifically speaking, the other universes would probably have to physically exist though some could be figments of imagination too, and would be incorporeal. 70.241.22.82 (talk) 18:51, 2 November 2010 (UTC)[reply]

A critical issue here is that "universe-splitting" is not an observable phenomenon in the formal definition of the many-worlds approach. So, philosophical pandering aside, "where are the other universes" is, by definition, an invalid question. There is no observable parameter for them - not an x-position, not a y-position, not a different time, place, or space, where the "other" universe is. "Other universe" represents an effort to use different plain natural language because "collapse" sounds catastrophic. All this boils down to is that the English language is a terrible medium for expressing quantum physics ideas. What we really mean by "many world interpretation" is
, where refers to the system, and refers to the apparatus used to observe it [4].
... and that is a superposition of states. All this nonsense about "interpretation" is little more than philosophical rumination about whether random systems can be causal; and whether causal systems are truly random. If more philosophers would agree on the definition of "random" then there would be no debate about "interpretation." Nimur (talk) 19:10, 2 November 2010 (UTC)[reply]
Not sure I agree with you there. Traditional Copenhagen quantum mechanics was incomplete in a pretty definite way: it included a special physical law that applied only to measurement devices, but didn't say what a measurement device was. Therefore, it couldn't predict the behavior of a system that might contain a measurement device. But it was impossible to settle the problem experimentally, because you would have to do something like a double-slit experiment with measuring devices. It's a practical impossibility to do that experiment with anything larger than a small molecule, and Copenhagen adherents can always claim, reasonably enough, that no small molecule is a measurement device. Nevertheless, there was a mathematical hole in the theory, even if it couldn't be tested, and that was the origin of the interpretation problem, I think. It's less clear that there's still an interpretation problem with the modern understanding of measurement, but many people think that the connection between amplitudes and probabilities still needs an explanation (though personally I don't).
(Also, don't you mean 〈φ|ψ〉 where |ψ〉 is the system and 〈φ| the measurement?) -- BenRG (talk) 22:59, 3 November 2010 (UTC)[reply]
You also have to define what "universe" means; this is no trivial task as throughout history, what constitutes the universe, even in purely scientific terms, keeps changing. Remember that before Edwin Hubble, it was widely assumed, even within the astronomical world, that the Milky Way Galaxy was the entire universe. Consider how small the Milky Way is in comparison to the observable universe, and it becomes really clear what a revolutionary thing this was. If you define the universe as "the sum-total of all creation", then multiple universes makes no sense. What you end up doing instead is reclassifying the thing we call "the universe" as a different entity, and pushing the limits of what the universe is "outwards", much as what Hubble did. --Jayron32 21:02, 2 November 2010 (UTC)[reply]
Does matter outside of the border of the matter resulting from our big bang count as another universe, or is everything that you can get to by three-dimensional travel part of the same universe? —Preceding unsigned comment added by 205.193.96.10 (talk) 20:57, 3 November 2010 (UTC)[reply]
As Jayron said, it's a matter of definition. Other galaxies were once called "island universes" (a term introduced by Kant in 1755, according to the Galaxy article). I assume that the current "multiverse" fad will either blow over or become accepted fact, and in the latter case people will start using "universe" for what they're now calling the "multiverse". That "multiverse" is different from both the "worlds" of the many-worlds interpretation and from areas beyond the big bang cosmos. All of those might exist or not, independently. -- BenRG (talk) 02:15, 4 November 2010 (UTC)[reply]

Well, thank you for the discussion, everyone. I'm definitely out of my depth here, but this is food for thought nevertheless. Have a nice day, 62.241.87.223 (talk) 21:23, 4 November 2010 (UTC)[reply]

Origin of a "love bite"

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I cannot find any information on why animals and humans do this affectionate bite. Is it a way of communicating "Look, I could bite you hard, but instead I'm tenderly biting you?" AdbMonkey (talk) 17:16, 2 November 2010 (UTC)[reply]

For humans (no idea about animals): because it feels good? Can also indicate (playful or not) dominance, which many people enjoy from one side or the other. → ROUX  17:17, 2 November 2010 (UTC)[reply]
The OP is specifically asking for (presumably expert or at least reliable) information, not just personal speculation... --Mr.98 (talk) 18:18, 2 November 2010 (UTC)[reply]
Male cats bite when mating, probably to immobilise and calm the female, and to balance the male. Cuddlyable3 (talk) 18:22, 2 November 2010 (UTC)[reply]
All kinds of animals do play bites. Looie496 (talk) 18:37, 2 November 2010 (UTC)[reply]
Please add any verifiable information you can find about this to our Love-bite article. DMacks (talk) 18:46, 2 November 2010 (UTC)[reply]

Cuddlyable, that was sort of what made me ask this question. My male cat does that to me sometimes when I pet him, and that got me thinking. Anyway, I know it exists among other animals too, but I could not find any info when I searched for it. The results only comes back with vampire literature, from what I've seen. AdbMonkey (talk) 20:13, 2 November 2010 (UTC)[reply]

The hickey, or love bite, is just a variation of kiss. The Wikipedia article has a brief section at Kiss#Biology_and_evolution which discusess some of the anthropological research into the purposes of kisses. It's pretty weak, but if you do some off-wiki research into the kiss as a psychological, social, or anthropological phenomenon, you could apply most of what you find to something like the love bite. --Jayron32 20:54, 2 November 2010 (UTC)[reply]

See picture no. 5 here. As for the domestic cat, the male (lion) gently bites the back of the female's neck. This is to make the female passive. It is using the natural hard wired instinct of the kitten (and when, adult the cat) to go limp when picked up by the mother by the scruff of the neck to be carried to safety. Other sources[5],[6] (the 2nd source gushes about cat sex). Cuddlyable3 (talk) 19:05, 3 November 2010 (UTC)[reply]

Ok, so maybe its just with cats, lions and domesticated animals like dogs, who will gently mouth you when you play with them. Thanks for the info. AdbMonkey (talk) 18:26, 4 November 2010 (UTC)[reply]

what chemical gets released when you miss someone?

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I know there must be some sort of biochemical that is released in a "flood" if I think the right thought or of the right person (that is no longer around) or hear the right song, the kind that pulls your heartstrings so. I suppose it might be "the nostalgia hormone" (or neurotransmitter) -- at least because there seems to be a strong physiological response. I know oxytocin and vasopressin seems to be involved in pair bonding, but is it these related hormones that get released or is it something else?

Are there any antagonists you can take to suppress this feeling? John Riemann Soong (talk) 18:56, 2 November 2010 (UTC)[reply]

C2H5OH will take it right away. -Atmoz (talk) 20:48, 2 November 2010 (UTC)[reply]
In my experience that's not a very useful antagonist and in fact often exacerbates it and upregulates all emotions (see short term effects of ethanol). John Riemann Soong (talk) 20:50, 2 November 2010 (UTC)[reply]
You're meant to take it with company, not while editing Wikipedia. Physchim62 (talk) 22:05, 2 November 2010 (UTC)[reply]
I was making a serious scientific inquiry! But...I never drink by myself, seeing how as I am below 21 this usually means I have to rely on others to furnish drinkable EtOH for me. John Riemann Soong (talk) 22:41, 2 November 2010 (UTC)[reply]
There are a number of other hormones that are involved in love, in addition to the two you've already mentioned: dopamine, phenylethylamine, adrenaline, and endorphin. I'm getting this from hubpages.com/hub/Hormones-and-love , which I apparently can't link to without triggering a spam trap filter. There's also a more technical article about the chemistry of love here. And at least some of those chemicals (e.g. dopamine) are addictive, so I suspect that missing someone you love might be at least partially due to withdrawal. Red Act (talk) 22:51, 2 November 2010 (UTC)[reply]
Yes, but withdrawal is a chronic condition. How would I identify the chemical that gives you that "shiver down your spine" when you have a flood of memories? John Riemann Soong (talk) 23:15, 2 November 2010 (UTC)[reply]
Missed one: prolactin, which is tied to dopamine. Red Act (talk) 23:18, 2 November 2010 (UTC)[reply]
Chemical basis for love might help point in some right directions, too. Red Act (talk) 23:30, 2 November 2010 (UTC)[reply]

The top expert on "separation distress" is Jaak Panksepp, and his book Affective Neuroscience reviews what is known about the system very thoroughly. According to his review, the main agents that increase separation distress are CRF and some types of glutamate receptor agonists. There are a number of agents that strongly reduce separation distress. The ones that have the strongest effects are opiates such as morphine and heroin; oxytocin and prolactin also have potent distress-reducing effects. Looie496 (talk) 17:57, 3 November 2010 (UTC)[reply]

crabs

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do crabs make sounds, analagous to our speech? how big do they get, and can they regenerate limbs? If so, how long does the latter take? 70.241.22.82 (talk) 19:00, 2 November 2010 (UTC)[reply]

Did you try reading crab? (assuming you mean the oceangoing variety, and not the pubichairgoing variety). The section titled "Behaviour" discusses communication methods. Many crabs may regenerate limbs, see Florida stone crab for one famous example, likely most crabs can do this. As far as how big they can get, well, there are hundreds of different species of crabs, but the largest in terms of size and weight is the Japanese spider crab, which can reach up to 12 feet in size from claw tip to claw tip, and can weight up to 40 pounds. --Jayron32 20:50, 2 November 2010 (UTC)[reply]
Your crab article must be different to mine, I found it useless! SmartSE (talk) 21:07, 2 November 2010 (UTC)[reply]
(edit conflict)Crabs can make sounds, but they are stridulations, rather than vocalisations. The abstract of this paper describes them in Trizopagurus and this does in Hemigrapsus oregonensis in more detail and there are many more examples in the literature. How big they get will depend on the species, but these guys can get up to 3.8 metres! Fiddler crabs can regenerate limbs e.g. but I can't find anything about how long, but it will certainly take at least one moult and maybe more for it to return to its full length. SmartSE (talk) 21:07, 2 November 2010 (UTC)[reply]

Ok, thanks! :) 70.241.22.82 (talk) 22:09, 3 November 2010 (UTC)[reply]

Microarray cost

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How much does a typical microarray experiment cost, supposing you wanted to assess differences in gene expression between two/three/four samples? Are there cheaper versions which assses fewer genes (e.g. genes known or suspected to be involved in muscle growth, maintenance, differentiation etc)? --129.215.47.59 (talk) 20:46, 2 November 2010 (UTC)[reply]

Cartoon physics law break

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Remember the classic cartoon where a character walks off the edge and "hangs" in the air before he falls down. My teacher wants me to answer what physics law does this cartoon breaks. Please help! Any clues or hints appreciated!!! --Tyw7  (☎ Contact me! • Contributions)   Changing the world one edit at a time! 20:47, 2 November 2010 (UTC)[reply]

When you step off the edge of a cliff yourself, what causes you to fall? Comet Tuttle (talk) 20:48, 2 November 2010 (UTC)[reply]
You should learn, and go back to your teacher with, some of the stuff outlined at General Relativity and blow their mind... --Jayron32 20:56, 2 November 2010 (UTC)[reply]
This is the actual cartoon: http://img213.imageshack.us/img213/2044/cartoonfall.png --Tyw7  (☎ Contact me! • Contributions)   Changing the world one edit at a time! 21:03, 2 November 2010 (UTC)[reply]
As a hint which might help, the law was figured out by Isaac Newton. (Albert Einstein later figured out something that was more accurate.) Red Act (talk) 21:56, 2 November 2010 (UTC)[reply]
The cartoon character has weight W which is a force acting on him continuously. When he walks off the cliff he hangs there for a short time. In physics we say his acceleration is zero. Then he suddenly starts falling downwards. In physics we say his acceleration is a and it is non-zero. So for a short time the cartoon character's acceleration is zero, even though the resultant force on him is greater than zero. Which of Newton's Laws of Motion does this violate? Dolphin (t) 21:58, 2 November 2010 (UTC)[reply]
What I've noticed in such cartoons is that the character does not begin to fall until he REALIZES that nothing is under his feet. Edison (talk) 22:04, 2 November 2010 (UTC)[reply]
Wow, there are actually two different "laws" that Newton came up with, that could to be said to be violated by that cartoon. The "law" I was thinking of wasn't one of the laws of motion. I'm not actually sure which law is the answer the teacher is looking for. I think the answer I was thinking of would be more likely if Tyw7 is younger, and the answer you’re thinking of would be more likely if Tyw7 is older. I don't know what the cutoff age would be. Red Act (talk) 22:22, 2 November 2010 (UTC)[reply]
The cartoon character is usually used to teach the laws of motion, and the character breaks two of them. So, the question is: "which ones and WHY?" Physchim62 (talk) 23:02, 2 November 2010 (UTC)[reply]
Jeez, I'm just not seeing it. The character violates one of NLM in a very straight-forward way. If it violates another of NLM, it's in a less obvious way. The other law of Newton's that I was thinking of wasn't one of NLM.
However, there is also at least a third valid answer, although I highly doubt it's the one the teacher's looking for. Namely, there's a law by Euler that's closely related to one of the two of Newton's being discussed. I guess this is another one of those cases where the "correct" answer is whatever you've covered in class recently. Red Act (talk) 01:06, 3 November 2010 (UTC)[reply]
Try doing a vectorial analysis of the supposed trajectory, and you should see two separate NLM breaches (I can't be more clear because of our homework rules) Physchim62 (talk) 01:28, 3 November 2010 (UTC)[reply]
Ah, OK, I see it now. So there are least four physics laws that would be correct answers, assuming the answers haven't been restricted to NLM. Red Act (talk) 02:02, 3 November 2010 (UTC)[reply]
It could also be the case that the character is standing on a high-pressure column of air, that had formed and hadn't dissipated yet due to a violation of the Second law of thermodynamics. Or that the air pressure under the character's feet is higher than expected, due to a violation of Boyle's law, or the ideal gas law. Or maybe a temporary violation of Coulomb's law is causing the force due to little charges built up on the character and the earth to be large enough to hold the character away from the earth. I'm sure I could come up with more, especially if I move on to physical laws that don't happen to have the word "law" in their name. Red Act (talk) 08:51, 5 November 2010 (UTC)[reply]
Look, there are two laws being violated. break it down into two steps:
  1. the character is moving forward at a steady forward pace, he takes what looks like 2 or 3 steps past the edge, stops, then falls straight down. how does he stop when he's moving forward and has nothing to push against to stop himself? what law is that?
  2. Again, the character is walking along on the ground without flying off into space on each step (think about how astronauts bounce on the moon). What force is it that holds him on the ground as he walks? When he walks off the edge of the cliff what happens to that force that was holding him to the ground, since the ground is no longer there to be held to?
Think about it. --Ludwigs2 01:39, 3 November 2010 (UTC)[reply]

If the planet that the cartoon character was standing on (along with the character himself) was moving up (relative to the character) at a speed of c minus 9.8, then could the character hover in mid air after one second of acceleration to avoid going faster than light? 205.193.96.10 (talk) 16:11, 3 November 2010 (UTC)[reply]

No, the relative velocity with respect to the planet would be less than c anyway: a lorentz contraction of length would be the apparent effect, not a period of stationarity. Nimur (talk) 17:20, 3 November 2010 (UTC)[reply]

Technically if you've been standing on a solid surface and then suddenly it's gone, you fall in very much the way that Wile E. Coyote does: lower parts first, with the upper parts remaining suspended for a little while. This is because only the soles of your feet are directly supported by the ground; higher parts of your body are supported by lower parts, and it takes a short time for the information that your feet are no longer supported to propagate upward. With the internal pressure supporting your body gone, you also get a little taller when you fall, but initially your body will overshoot that size and get even taller than that, before springing back—again, like Wile E. Coyote. All of these effects are too small/fast to be seen, unfortunately. -- BenRG (talk) 22:23, 3 November 2010 (UTC)[reply]

How about if you dropped the supporting floorboard out from under a spring or a slinky? I bet you could make a fun video from that, and make some physicists' heads hurt trying to balance mass flux against a continuously variable spring-constant. Nimur (talk) 00:19, 4 November 2010 (UTC)[reply]
Actually, if you managed to make the ground support disappear instantaneously (about the only way you could approximate this in the lab would be to have an iris-type mechanism that opened up a hole by pulling the support sideways in all directions at high speed), then the body would drop as a unit (gravity is simultaneously affecting all portions of the body equally); you'd only see a Wile E. Coyote drop if (a) Wile E. was tall enough so that the top of his head was experiencing a significantly smaller gravitational pull, or (b) the acceleration of the ground away from the feet was slow enough so that the body engages in a reflex effort to maintain position (basically a jump, where the legs kick down trying to push the body up away from the fall). --Ludwigs2 05:10, 4 November 2010 (UTC)[reply]
Not really. Within measurable limits, for earth-person type gravity, yes, you should not see any measurable "stretching" associated with the Wile E. Coyote-type fall. However, tidal effects do exist, even if they are below the limit of measurement for this specific scenario. With very large gravitation, you can get measurable effects of this type, see Spaghettification. The effect exists for all gravitational pulls, but is merely insigificant (but not nonexistant) for the scenario describes. --Jayron32 05:21, 4 November 2010 (UTC)[reply]
No, even without tidal forces or jumping, your head remains motionless for a nonzero time. Gravity acts on your whole body, but it's already doing that before the ground is removed. All that changes when the ground is removed is the contact force on your feet. The speed at which your neck can learn about the change is limited by the speed of light, and in practice it's the much slower speed of sound in your body. Until then, it has to continue to support your head against gravity just as though the ground was still there. (Also, another way to get rid of the ground "instantaneously" would be to pull it downwards with an initial acceleration larger than 9.8 m/s², although I guess that might run into difficulties with air turbulence.) Nimur, I don't think this will work with a Slinky because the governing speed will be the speed of sound in the metal/plastic that it's made of. I wonder if there is some way to make a visible demonstration of this with some combination of a carefully chosen spring and high-speed photography. Someone must have tried it. -- BenRG (talk) 08:29, 4 November 2010 (UTC)[reply]

Hmm surprised no one linked to Cartoon physics yet Nil Einne (talk) 12:07, 4 November 2010 (UTC)[reply]

Quail genome?

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Is there a publicly-available database of the genome sequence for the quail (ideally Coturnix japonica)? ----Seans Potato Business 21:48, 2 November 2010 (UTC)[reply]

I was able to find this but it seems limited to Colinus virginianus at this point. The pubmed abstract (here) suggests that it will be "integrated with Japanese quail (Coturnix coturnix) data in future builds" so maybe there isn't such a thing as a publically-available Coturnix japonica genome yet. Good luck! --- Medical geneticist (talk) 23:19, 2 November 2010 (UTC)[reply]
Yeah, there doesn't seem to be anything available at the moment. I managed to find a sequence of interest as coding DNA only and I suppose that will have to do. :) ----Seans Potato Business 17:59, 4 November 2010 (UTC)[reply]

Why does high temperature cause distant sights to "blur", and can this be replicated at room temperature?

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Greetings.

For years, I've been fascinated by what I've seen at a local pizza place. The pizza oven is about 25 feet behind the counter, and (when I stand in front of the counter) the area surrounding the oven —and everything in it— appears "blurry" and very distorted to me.

What exactly causes this visual phenomenon? Are light particles excited (or even ionized) by high temperatures?

Also, can a similar visual effect be achieved AT ROOM TEMPERATURE through any known means?

--Thank You! Pine (talk) 22:44, 2 November 2010 (UTC)[reply]

What you're seeing is a kind of mirage, caused by the hot air from the ovens. To explain it very quickly, the way that light travels through air depends on the temperature of the air: so when you have differences in air temperature over a short distance, you get strange effects.
A similar effect can be created at room temperature, but not easily. You need a large amount of gas that's different from air within your visual field, and that is usually a sign to get the **** out of the place. You can see it sometimes when natural gas is released at a gas well. Physchim62 (talk) 23:13, 2 November 2010 (UTC)[reply]

To elaborate the explanation above, the hot air has a different refraction index than the cold air. Because of that light rays will bend a little bit when they move in and out of the hot air area. that causes the image distortions that you observed. 76.123.74.93 (talk) 02:40, 3 November 2010 (UTC)[reply]

To attempt an answer to your "also" ... I can't think of any way to reproduce this in air all at room temperature, except by blowing a gas with a different refractive index in a way that produces turbulence in the mixing with air. (later) Sorry, I've just noticed that Physchim62 said that! The temperature effect in air can sometimes be seen on a small scale with domestic fires and radiators, and will be in evidence outside on Friday in some countries. Dbfirs 08:07, 3 November 2010 (UTC)[reply]
Is it correct to say that hot air has a different refraction index than the cold air entirely because of the different densities, or does the temperature itself have anything directly to do with it (other than changing the density)? -- 58.147.58.203 (talk) 08:20, 3 November 2010 (UTC)[reply]
Several websites claim that "Refractive index is proportional to the square roots of electrical permittivity and magnetic permeability. These factors may change with temperature, but not linearly, and therefore RI does not have a simple relationship with temperature." so I suspect that hot air at the same density (from greater pressure) will have a marginally different RI from cold air at the same density. This difference will be swamped by the difference in density at normal pressure. Dbfirs 08:35, 3 November 2010 (UTC)[reply]
I'm not sure if this counts as "room temperature" but if you light a candle you may be able to see the same phenomena just above the flame. 92.15.0.194 (talk) 14:37, 3 November 2010 (UTC)[reply]
Obviously that does not count as room temperature. Put your hand on the flame for a few seconds and you will agree with me. 67.78.137.62 (talk) 15:02, 3 November 2010 (UTC)[reply]
That depends upon how the OP defines room temperature. 92.24.178.95 (talk) 17:38, 3 November 2010 (UTC)[reply]

If you observe over a much larger distance (say, looking across a large valley), you can see thermal "shivering" effects that are due to minute temperature variations (a few degrees, say), but because the lengths are much longer, the refraction can be visible. And if you are into astronomy, you can see atmospheric twinkling - a type of scintillation - due to vertical thermal gradients and inhomogeneity in the atmosphere. Nimur (talk) 17:24, 3 November 2010 (UTC)[reply]

Relationship between octane rating & emission levels

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Consider two identical cars, one using low octane gasoline, the other high octane. Same driving conditions. Does one car create less emissions than the other? Thanks, CBHA (talk) 22:56, 2 November 2010 (UTC)[reply]

Does not quite work like that. One could have a large megawatt, electrical generator, running on natural methane with a 14:1 compression ratio, producing a very clean CO2, water vapour, nitrogen exhaust. Or a high compression ratio, in WWII fighter aircraft, sports car, racing car, all with short stroke engines and the exhaust can be very, very dirty.--Aspro (talk) 23:28, 2 November 2010 (UTC)[reply]
Okay. But suppose the cars are conventional mass-produced cars (not racing cars, fighter aircraft, or stationary generators) running on the grades of gasoline that are generally available (say octane # 91 and octane # 87.) CBHA (talk) 00:46, 3 November 2010 (UTC)[reply]
Makes no difference. Either you need the octane or you don't. If you need it and you don't use it the car knocks. If you don't need it and you use it, it does nothing at all. Ariel. (talk) 00:55, 3 November 2010 (UTC)[reply]
I've seen suggested (but do not have a source offhand) that using fuel with an octane rating higher than recommended can result in incomplete combustion. In either case, using incorrect fuel cannot improve your engine's performance or its emissions, and may be detrimental to both. — Lomn 01:42, 3 November 2010 (UTC)[reply]
I've noticed that most filling stations near where I live (UK) supply only 95 (RON) (equivalent to 90–91 US AKI). I presume that all British cars are now built and tuned to this octane fuel rating. Some modern engines have sensors that detect knocking and adjust the timing. They are not designed to adjust to the octane rating, but might have that effect to a limited extent. There seems to be lots of opinion on the web about higher octane possibly providing more power or better fuel consumption, or possibly helping to burn out exhaust valve seats because of late burn. Is all of it just uninformed speculation? I'm inclined to agree with Aspro, Ariel & Lomn above. The manufacturers spend millions of pounds in developing and testing their engines, and in reducing emissions to meet regulations (and reduce road tax in the UK). Their recommendations are likely to be the optimum for that engine. Dbfirs 14:00, 3 November 2010 (UTC)[reply]
Lomn, see Tetraethyllead which is still sometimes added to increase the octane of gasoline (petrol) but also adds to lead pollution. Cuddlyable3 (talk) 14:05, 3 November 2010 (UTC)[reply]
Dbfirs - There are a select few specialist garages (http://www.petrolprices.com/about-fuel.html) selling the old 4 star leaded fuel (98 RON) for "classic cars" - at a price! Everybody else has to use the single unleaded 95 - or diesel, which I guess is >40% of cars here now - due to far better consumption rate - I get easy 50+ per gallon (2L Ford Mondao).  Ronhjones  (Talk) 23:11, 3 November 2010 (UTC)[reply]
Thanks, Ron. Fortunately, I don't need old 4-star (because I can't afford to run a classic car). I envy you your fuel consumption figure. Can you achieve that rate consistently over time (including short runs, manoeuvres etc.) or only on a long run? Dbfirs 08:56, 4 November 2010 (UTC)[reply]
From discussion in a vintage car club I gather that valve seats in older cars wear badly if run without leaded fuel. Separate additives for unleaded fuel are available. Cuddlyable3 (talk) 08:31, 4 November 2010 (UTC)[reply]

Which animals are truely monogamous?

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I've read that in nature, true monogamy is very rare and that even in species that tend to pair up for life, 'affairs' and side-pairings are common. Could you tell me some of the few species that are 100% monogamous? I think that the Peach-faced Lovebird is one of them. --95.148.105.15 (talk) 23:50, 2 November 2010 (UTC)[reply]

Photocorynus spiniceps --Dr Dima (talk) 01:55, 3 November 2010 (UTC)[reply]
Are humans truly monogamous? "Affairs" and side-pairings are very common in human societies too. --99.237.232.254 (talk) 02:11, 3 November 2010 (UTC)[reply]
No one said they were. The Masked Booby (talk) 02:24, 3 November 2010 (UTC)[reply]
I was wondering if, by the OP's criteria, humans would be considered truly monogamous. --99.237.232.254 (talk) 06:00, 3 November 2010 (UTC)[reply]
I would say the answer is clearly no, in fact we're probably less monogamous then many of the common animal examples on average. However you do have a point it's not clear if the OP is aware of that. Nil Einne (talk) 06:04, 3 November 2010 (UTC)[reply]
Bald Eagles are monogamous, with the following caveats mentioned in their article: It is thought that Bald Eagles mate for life. However, if one member of a pair dies or disappears, the other will choose a new mate. A pair which has repeatedly failed in breeding attempts may split and look for new mates. Seems reasonable to me. The Masked Booby (talk) 02:24, 3 November 2010 (UTC)[reply]
I don't know if that would rule out 'affairs'. Very often animals which appear to mate for life are found to mate with other partners on the sly (this can sometimes be difficult to observe but the recent advances in genetic analysis making paternity or parentage testing easy have shared a lot of light in this area including with the animal we discussed above before TMB's comment), and this includes both sexes. However [8] found a high degree of fidelity in another species of eagle (by analysing DNA from feathers). On the other hand [9] claims recent research suggests that it may not be true but doesn't mention how so or what research nor even what it means by 'recent'. Prairie Vole are another common 'icon' of monogamy and studied for how they are adapted for it [10] but our article mentions they aren't always sexually faithful. Back to birds, [11] suggests low instances of extrapair copulation and extrapair parentage may be more common among isolated island populations where the genetic variation is low. Nil Einne (talk) 06:01, 3 November 2010 (UTC)[reply]
As far as I am aware, the European Herring Gull is mostly monogamous (a percentage of individuals aren't) - and often pairs up for life, though if one parter dies, the other will attempt to find another mate. Are there actually any non-human animals that will never pair up again if their chosen mate dies? I've never heard of any. Even Lovebirds will do this. It's a myth that if one dies, the other will die shortly after through loneliness/a broken heart (na, they just go find another partner when the breeding season comes round again). --Kurt Shaped Box (talk) 14:05, 3 November 2010 (UTC)[reply]
If you are looking for a species in which 100% of males mate with exactly zero or one female in their lifetimes (and vice-versa), such a thing simply does not exist. In species that display Pair_bonding there are always exceptions and 'affairs', such as the OP suggested. You may enjoy the book mentioned in our article called The Myth of Monogamy. Also a recent book covering human monogamy and evolution is getting some attention, it's called Sex_at_Dawn. Essentially, though pair-bonding and monogamy can be evolutionarily favorable for some species, it is unexpected to find any behaviour displayed by 100% of individuals. SemanticMantis (talk) 15:43, 3 November 2010 (UTC)[reply]
The best possibilities I would see to fulfill the monogamous qualifications would perhaps be insects that do not live long enough to mate more then once. Googlemeister (talk) 15:52, 3 November 2010 (UTC)[reply]
I was thinking of mayflies is response to the original question but, even then, it's hard to be certain. Many insect species will usually only mate once in their entire lifetime, but you can get occasional behaviour where a female will mate with more than one male: it is to be expected in evolutionary terms, as long as the resource cost isn't too high, as it effectively "hedges her bets" on the genetic quality of her offspring. Physchim62 (talk) 16:02, 3 November 2010 (UTC)[reply]
Yes, I was thinking along the same lines e.g. male ants mate zero or once so the males are monogamous (although queens of many species mate more than once)...so, semi-monogamous-ish. Sean.hoyland - talk 16:12, 3 November 2010 (UTC)[reply]
Good point Sean, I think most drones die after first copulation. Though males of obligate Semelparous species are likely to mate with zero or one females, the females of such species tend to have multiple mates. And of course, a queen being inseminated by multiple males (in the same day) after which the males all die is probably far from most notions of 'monogamy' ;) SemanticMantis (talk) 17:29, 3 November 2010 (UTC)[reply]
See Monogamous pairing in animals. -- Wavelength (talk) 22:46, 4 November 2010 (UTC)[reply]

Do people really eat spiders in their sleep?

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(2) What's with the "on average people eat X number of spiders during sleep"? Do spiders climb into their mouth? Dont you die after eating raw spider? Thanks Money is tight (talk) 02:58, 8 November 2010 (UTC)[reply]

According to Snopes, no. --- cymru lass (hit me up)(background check) 03:40, 8 November 2010 (UTC)[reply]
Also, I don't think you die after eating raw spider. In fact, many people around the world eat insects as food. TomorrowTime (talk) 07:31, 8 November 2010 (UTC)[reply]
I recall a National Geographic program where they were in a South American jungle, where the spiders are quite large. Natives would capture them, roast them alive, and eat the meat from the legs, like you would with crab. The roasted arachnid meat was said to taste like shrimp. As far as dying, most house spiders are mostly harmless. If a seriously venomous spider such as a black widow or a brown recluse got into your mouth and managed to inject some venom, that could be trouble. But cats, for example, will attack common house spiders and eat them, with no apparent damage. ←Baseball Bugs What's up, Doc? carrots08:54, 8 November 2010 (UTC)[reply]
This is entertainment..... ??!! Ghmyrtle (talk) 09:01, 8 November 2010 (UTC)[reply]
Theoretically, you'd be in greater danger from swallowing a fly, considering where they spend much of their short existence. And for the entertainment part of this, please rise and join us in singing, "There Was an Old Lady Who Swallowed a Fly". ←Baseball Bugs What's up, Doc? carrots09:03, 8 November 2010 (UTC)[reply]
She did swallow a spider too[12] (with the aim of catching the fly) but an unpleasant side-affect was internal wriggling, wiggling and tiggling. Whether these are recognised medical conditions, I don't know. Alansplodge (talk) 13:18, 8 November 2010 (UTC).[reply]
Yes. It seems likely that the critter would quickly be smothered by various internal fluids, so it wouldn't get to do much wriggling and wiggling and tickling. ←Baseball Bugs What's up, Doc? carrots13:23, 8 November 2010 (UTC)[reply]
The bovine and equine stages of the therapy seem a bit unlikely too. Should have a "citation needed" tag. Alansplodge (talk) 17:12, 8 November 2010 (UTC)[reply]
Having a local environment made up of hydrochloric acid, enzymes and the like would probably limit the wriggling and tiggling in favor of dying and dissolving fairly promptly. FT2 (Talk | email) 19:09, 8 November 2010 (UTC)[reply]
The Straight Dope handles the question here. APL (talk) 20:46, 8 November 2010 (UTC)[reply]
Cecil is using logic and reasoning, whereas Snopes (listed earlier) claims to have found the source of the urban legend. Between the two, it seems like the question has been solidly answered. ←Baseball Bugs What's up, Doc? carrots20:51, 8 November 2010 (UTC)[reply]
Additional information about bees not directly related to the OPs question

If she would have swalloed a bee or wasp or any other related incect, she would have suffered sever stings, because the stinger would poke the stomach walls while in digestion. What do you guys think would happen if she swallowed a bee or wasp? As for spiders, I accidentaly ate one, i threw up. I guess some people's systems don't get along with spiders, doesn't mean they are unsafe to eat. I'm not saying go eat a spider, i'm saying. Definately don't eat a bee, or even a spruice beedle. People have consumed incects in the past, either for survival if they were lost or something, for sport, or even for dair. I don't think people eat incects in their sleep. It's not a good idea though, as the incects could have paracites and other diseases on them that could be harmful to the body. And incects such as bees like i said above, can really hurt your digestive system. 204.112.104.172 14:14, 11 November 2010 (UTC)