Wikipedia:Reference desk/Archives/Science/2007 August 2

= August 2 =

volkswagon beetle
How long is a volkswagon beetle from bumper to bumper?
 * Not sure about other models, but the 2008 one is 161.1 inches long. Edmunds H YENASTE 01:03, 2 August 2007 (UTC)


 * The classic bug was almost exactly the same length: 160.6 inches. The 'SuperBug' was just three quarters of an inch longer at 161.3 inches. SteveBaker 02:26, 2 August 2007 (UTC)

I was wondering
I was in my swimming pool today and I saw a really big (about 2 inches) black wasp or hornet. It flies very fast and it came out of a small hole in the ground. I did some looking on here for "ground wasp", "ground hornet", "giant hornet", "black wasp", ect. but to no avail. Looks kind of like the white faced one but their was no white it was black and a real dark blue. So yeah just wondering what it is.... Oh yeah, I live in Lansing, Michigan if that helps narrow your search.


 * What you saw was probably a pompilid wasp, or spider wasp. The family Pompilidae is quite large with more than 4000 species. Many species are all black. They are called spider wasps, because the female of many species when ready to lay eggs hunts for a spider and then stings it. The sting does not kill the spider, but paralyzes it. The female than carries the spider (either by flying or by dragging) to a nest that the wasp has dug. It hauls the spider down into the hole, lays a single egg on the spider, and then seals the hole. The egg hatches and feeds on the paralyzed spider. When the larva matures it digs out of the nest and flies off. Fascinating and horrifying at the same time.--Eriastrum 16:43, 2 August 2007 (UTC)

Blue Whale Migration
How long, in km, is the migration route of the blue whale? or How far does a typical blue whale travel in a year?
 * Try this page from the Whale and Dolphin Conservation Society. It doesn't seem to give any exact figures, but should allow you to work something out. --jjron 08:28, 2 August 2007 (UTC)

Breath Holding
What is the average time that an adult male can hold their breath underwater? The Apnea article doesn't have any precise figures. Links to a chart of some sort (which I failed to find on-line) would be appreciated. I managed 3.5 minutes recently and was curious how normal (or abnormal) that is. Sjmcfarland 05:14, 2 August 2007 (UTC)
 * Free-diving and Apnea have some info related to this. 3.5 minutes seems pretty long! Flyguy649 talk contribs 05:21, 2 August 2007 (UTC)
 * I used to be able to hold my breath 1 and a half minutes and that was longer then most of my friends, we used to have little competitions. Three and a half is very long, you must have very high anaerobic fitness or you're pulling our collective leg ;)Vespine 06:41, 2 August 2007 (UTC)
 * I suppose I am my only witness. However, if you look through my contributions you'll see that some of them concern Quito, Ecuador, the city I grew up in, which is at an altitude of nearly 10,000 feet. Perhaps lower oxygen levels lead to higher lung capacity? Also, I did the hyperventilation trick which the Apnea article strongly recommends against. If anyone happens to find a chart of averages, put a link up to satisfy my curiosity. Or perhaps no such chart exists because scientists have better things to do than to see how oxygen-deprived they can get their test subjects;) Sjmcfarland 08:09, 2 August 2007 (UTC)
 * Harry Houdini performed many of his tricks largely as a result of being able to hold his breath for an extraordinarily long period of time. This is usually stated as 'over three minutes', and is often regarded as being at the upper limits of human ability, though if I remember properly I think I have heard claims of around five minutes. I think for the average untrained person, they would struggle to do much better than a minute (as Vespine said you can train yourself to improve this). Also you are right, living at a high altitude certainly will improve the ability of the blood to hold and carry oxygen (it increases the red blood cell count). This is the reason athletes do altitude training, and is also the basis for blood doping and the reason for the use of the drug EPO, which as recently as the last week has seen two of the top competitors kicked out of the Tour de France. --jjron 08:42, 2 August 2007 (UTC)
 * David Blaine managed 7.5 minutes in "Drowned Alive", and the article also states that the world record is nearly 9 minutes. I don't know about average, though, he had special training for the stunt.Capuchin 09:36, 2 August 2007 (UTC)
 * When a magician does a breath holding demonstration, there is a very strong liklihood that it is a trick, because that is what magicians do. Houdini, for instance, would be out of the trunk before it was dropped in the river, whenever possible. I would assume that amazing feats of endurance are tricks when a magician does them, just like escaping from fake strait jackets or trick handcuffs, or surviving being sawn in half.Edison 14:30, 2 August 2007 (UTC)
 * I remember watching a documentary about some sort of divers who hold their breath so much, one guy could hold his breath for 5 minutes, and others 3+ minutes. So 3.5 isn't that impossible, but I'd still be a bit skeptical about op's 3.5 minutes, unless op has some other training other than the natural 10,000 ft thing. Swimming a lot? Lots of excersize? --Wirbelwind ヴィルヴェルヴィント (talk) 22:32, 2 August 2007 (UTC)
 * Its very plausible. I held my breath for 3 minutes 45 seconds when I was 20 years old. Its largely a matter of having large lung capacity, overbreathing and being able to tolerate the discomfort and impending loss of consciousness. I do not recommend anyone try it because it is obviously a strain on the body. To believe Blaines claim I would have to hold him under water myself. Edison 23:35, 2 August 2007 (UTC)
 * Yes, David Blaine also once took his heart right out of his chest, on live TV!!!11! Vespine 00:41, 3 August 2007 (UTC)


 * I'd guess it would be good to practise this within sight, or at least ear-shot, of other people if you're hyperventilating first. Otherwise nobody will hear you hit the ground when you pass out and fail to automatically breath. :D Skittle 01:12, 6 August 2007 (UTC)

MOLECULAR BIOLOGY
WHY THE NORMAL HUMAN DNA IS TERMED AS B-DNA NOT AS A-DNA


 * See DNA. The gene for TYPING IN ALL CAPITALS has not yet been discovered in B-DNA - so please stop doing it. SteveBaker 11:48, 2 August 2007 (UTC)


 * I think the questioner may be wondering why B-DNA – the predominant conformation of DNA in living systems – didn't get the first letter of the alphabet. I'd guess it's some sort of historical accident, but if someone could shed some light I'd like to know for sure.  TenOfAllTrades(talk) 12:45, 2 August 2007 (UTC)


 * I don't know the history, but I'll make a guess. According to the A-DNA article, you find A-DNA "... in dehydrated samples of DNA, such as those used in crystallographic experiments...".  Remember, the helical structure of DNA was determined by images produced by X-ray crystallography.  Most likely, A-DNA was what they were seeing. --  JSBillings  13:13, 2 August 2007 (UTC)

There is some discussion of this at Rosalind Franklin and Maurice Wilkins. In his autobiography, Wilkins described his experience with the DNA sample he received from Rudolf Signer. This was the sample of DNA that was used for all of the experiments by Franklin, Wilkins and Raymond Gosling that led to recognition of the "B form" DNA. Wilkins found that when moist the Signer DNA was "snot-like" and that thin threads of hydrated DNA could be pulled out. By mounting groups of these DNA-containing threads in parallel to form a target for x-rays, Wilkins and Gosling got the best x-ray diffraction images ever obtained for DNA. They obtained their results with a stream of humidified hydrogen gas flowing over the DNA. Franklin was an expert in controlling the humidity of samples in x-ray diffraction experiments and spent her first efforts with Gosling completing a more compact device for obtaining x-ray diffraction images of DNA. With her experience and the new equipment, they were able to increase the humidity from 75% to 92%, allowing clear images of the "B form" DNA to be obtained for the first time. They started calling the first, less hydrated form the "A form" and the newly observed second form the "B form". --JWSchmidt 04:56, 6 August 2007 (UTC)

social studies
compare and contrast the means of livelihood of the early filipinos and the filipinos as of today.


 * Please check the guidelines at the top of the page: " Do your own homework. The reference desk won't give you answers for your homework, although we will try to help you out if there's a specific part of your homework you don't understand. Make an effort to show that you've tried solving it first." If this isn't an essay topic, I'll go he. --jjron 08:23, 2 August 2007 (UTC)


 * I'd start by looking at this link for the modern economy and this link find the period of history that corresponds to your teacher's definition of early Filipinos. Sjmcfarland 08:30, 2 August 2007 (UTC)


 * And it might be a better idea to take this type of question to the Humanities reference desk. Flyguy649 talk contribs 14:43, 2 August 2007 (UTC)
 * Yes, so the right contributors can tell you to do your own homework. Clarityfiend 16:09, 2 August 2007 (UTC)
 * Exactly ;) -- Flyguy649 talk contribs 21:34, 2 August 2007 (UTC)

Paralysis from spinal chord injuries
Hi, If you damage your spine can it ever happen that only one leg becomes paralysed while the other remains unaffected? What I mean is can someone end up with one leg working fine and the other one paralysed? --121.219.226.254 09:37, 2 August 2007 (UTC)


 * It is possible to damage only the motor neurons that enervate a specific limb, yes. This sort of specific injury is observed in some cases of poliomyelitis (polio); partial or complete paralysis of one or more limbs (in any combination) may occur depending on which motor neurons are affected and to what degree.
 * Mechanical trauma (gunshot wounds, etc.) or disease (tumour, blood clot) that affect only half of the spinal cord can also cause paralysis of one leg. See hemiplegia and Brown-Sequard syndrome for more information. TenOfAllTrades(talk) 12:39, 2 August 2007 (UTC)


 * I think you mean innervate not enervate! —Tamfang (talk) 02:59, 30 November 2007 (UTC)


 * Sure. When they're doing experiments on spinal injuries, in rats, they nick one side of the spinal cord only so that they can compare the two back legs, the injured one and the normal one. Gzuckier 14:36, 2 August 2007 (UTC)

the United Kingdom vs Great Britain
What is the geographical and political difference between the UK and GB? I am from England so why can't I be classified as English rather than from GB or the UK? For example when I purchase something online, normally my only option is to say I'm from the UK. England is a country in its own right why cannot I not be from England?


 * Well I too am English, and it is certainly a country in it's own right. However, it is governed along with the other constituent countries of Northern Ireland, Scotland and Wales, by the government of the United Kingdom and therefore that is how it will be referred to on international websites. This is a legal thing as a UK national, it's not denying your right to identify as English. As for the other question, Great Britain is the island consisting of England, Scotland and Wales. The United Kingdom is properly known as the United Kingdom of Great Britain and Northern Ireland. I hope the links give more details. Interestingly if asked for nationality on a form, with no given options I always put English. They can always turn it into GB or UK if they want. Cyta 11:47, 2 August 2007 (UTC)

NB There are also 14 British Overseas Territories, which the United Kingdom considers to be under its sovereignty, but not as part of the United Kingdom itself. None of them are in Great Britain. --Dweller 13:19, 2 August 2007 (UTC)


 * In summary ... the United Kingdom is a legal and political construction - it is what appears on your passport. Great Britain is a geographical entity - it is the name of an island. England is a country and English is a nationality. So your full description would be "an English citizen of the United Kingdom, resident in Great Britain". Gandalf61 13:39, 2 August 2007 (UTC)


 * The nomenclature has always been a bit of a mystery to United Stateans. If I understand correctly, from the above, if Ireland were given back to the Irish, then the enterprise could correctly be called Great Britain, but freeing Scotland would still not let the diminished kingdom be called "England" because of Wales? Edison 14:25, 2 August 2007 (UTC)


 * Yes - it's a bit of a mess. If Northern Ireland were to become a part of Eire (Ireland) - then the United Kingdom would cease to exist because it refers to the uniting of Britain (Scotland+England+Wales) and Nothern Ireland.  So if that happened we would presumably go back to talking about "Great Britain" (that being Scotland+England+Wales).  If Scotland were ever to gain total independence - we'd need a new name, but if that happened, I doubt it would be long before Wales would demand (and get) the same thing - so we could have England, Scotland and Wales as a true countries, each with its own government and so forth.  But that is pretty unlikely - the three countries are each too small to stand up in the international scene.  Giving Northern Ireland back to Eire is much more likely to happen now that doing so is not "Giving in to the demands of terrorists" - and it does make a certain amount of geographical and cultural sense - except that a majority of the people living there didn't want it to happen the last time we asked them.  But with an end to the violence, we can at least discuss it like rational human beings - and if we do it - it'll be in an orderly, peaceful manner...because, in the end, we're British dammit! SteveBaker 15:08, 2 August 2007 (UTC)
 * Although UK minus Northern Ireland would still contain a united kingdom of England and Scotland, since the two kingdoms have a single crown now. (I believe Wales was a principality (or group of principalities).) So the United Kingdom tag might still fit, technically speaking. Flyguy649 talk contribs 15:13, 2 August 2007 (UTC)
 * Moreover, take Northern Ireland out of the equation and you are still left with the Isle of Man and the Channel Islands, both of which are part of the UK, but not part of Great Britain. Rockpock  e  t  05:35, 3 August 2007 (UTC)
 * No they're not. —Tamfang 18:50, 6 August 2007 (UTC)

There is a difference between state, country and nation. For a lot of purposes (often monetary/trade) the state is the relavent construct since it is the state (the UK) that controls the currency. For the purposes of buting online it's irrelevant if you are english, welsh or scottish etc since you will be paying in the same currency UK pounds.87.102.67.227 17:04, 2 August 2007 (UTC)


 * Careful. You will only drag us into a lengthy discussion on whether you pay with the English Pound or the Great Britain Pound. Simon A. 18:20, 2 August 2007 (UTC)
 * (Or why you get them from the Bank of England). SteveBaker 01:17, 3 August 2007 (UTC)
 * A Pint is a Pound the World around. --Tbeatty 03:12, 3 August 2007 (UTC)
 * I suspect it's more than that, now. Last time I was in England it was only about 90p but that was some time ago. --Trovatore 06:04, 3 August 2007 (UTC)
 * Sixteen years ago we called pound coins "Beer Tokens" since our local pub charged one pound for a pint of their preferred brew - but by about fifteen years ago the price went over a pound - so by now, a pint must be costing considerably more. SteveBaker 11:02, 3 August 2007 (UTC)


 * Pints generally cost between £2-£3.50 depending on which area of England you are in. Going back to earlier comment about the unification through crown. If we were to release N. Ireland from the UK and Scotland were to fully govern itself (though still be Royally attached) where would that leave us? EMMA 14:36, 3 August 2007 (UTC)
 * Who is "us"? Wikipedians? If you are referring to England, then it would still be in union with Wales. Rockpock  e  t  17:25, 3 August 2007 (UTC)


 * Yes and England and Wales was called England, pre-act of union, but was renamed England and Wales (which still has it's own legal system) in 1967, so I assume we (England and Wales) would use that name. However we (UK) will probably all be absorbed into the United States of Europe before then (shame). Cyta 07:44, 6 August 2007 (UTC)

I love this question! to answer an earlier point, one's nationality is (i've always assumed) from what nation state you hail from. england is not a nation state so to say that you are english is not correct, you are a UK-er (!). obviously, this is linguistically nonsense (why isn't there a word?) no i just say i'm scottish (or european).195.195.248.252 10:08, 8 August 2007 (UTC)


 * The existence of a compound term nation-state ought to suggest that the nation and the state are not necessarily the same thing. The idea that the state (government) ought to match a nation (ethnic group) is relatively new, and the idea that the state defines the nation is even newer.  —Tamfang 17:51, 13 August 2007 (UTC)

spider pigs
what do spider pigs do? can I get one as a pet? where do they come from?
 * First you must be yellow, you must have four fingers at each hand, you must have only three hairs, you must have a pen in your brain and you must have consumed 106 cans of Duff in youd life, than and only than you can lift up a pig to the ceiling and it becomes a spider pig!--Stone 12:15, 2 August 2007 (UTC)


 * Doh!.--Shantavira|feed me 12:35, 2 August 2007 (UTC)
 * Actually a crayon in his brain, not a pen. Or at least if there's also a pen, we haven't heard about it yet. Hmm, can one say "actually" when talking about a cartoon-world thing? DMacks 15:17, 2 August 2007 (UTC)

I also would love to have a spider pig. I think the bigger question is what actually happened to Spider Pig at the end of the film?


 * Yeah - I was wondering the exact same thing - I was expecting him to somehow save the day and thereby justify Homer's instincts, which would have resulted in Homer being the hero still - but the little guy just kinda fell off the end of the plot. Weird. SteveBaker 14:56, 2 August 2007 (UTC)


 * The pig had to scoot off early to film the first episode of the Simpsons for next season. See He Loves to Fly and He D'oh's. -- Kainaw (what?) 16:47, 2 August 2007 (UTC)


 * He doesn't end up like Pinchy? --Tbeatty 03:13, 3 August 2007 (UTC)

Re:Solar flares, prominences, and sunspots
What phenomeneon happens on the photosphere and chromosphere of the Sun? Our class is having a heated argument about it. Our textbook says sunspots and prominences happen on the photosphere, and solar flares on the chromosphere. However, a Ministry-approved educational disc states everything happens on the photosphere. And the Wiki says so too. But there are several old books that say so-and-so happens on the photosphere while solar flares happens on the chromosphere. -- Zachary crimsonwolf  12:15, 2 August 2007 (UTC)


 * Well, according to wikipedia, sunspots are phenomena of the photosphere, solar prominences are 'anchored' to the photosphere but extend into the corona, while flares occur in the chromosphere and corona. What ministry is this, anyway? Algebraist 12:35, 2 August 2007 (UTC)

A Ministry of Education. I'm not really sure about the content of the disc, though. But my teacher said that everything happens on the photosphere. To top that off, I'm having a major public exam coming in the next 2 months (an equivalent of your A levels, or slightly lower). -- Zachary crimsonwolf  13:34, 2 August 2007 (UTC)

Pinhole_camera
With current CCD's or other electronic image capture devices is it possible to make a handheld pinhole camera that is easily useable under everyday conditions (eg shutter speed < 1/30sec)?


 * In bright sunlight, sure. In any weaker lighting, you're not going to get good results without a lens, or long exposure times. —Keenan Pepper 20:26, 2 August 2007 (UTC)


 * For a pinhole camera to work well you need a very sensitive sensor and present day ccd's aren't more light sensitive than film. Less even, I believe. But the sensor is smaller, which might cause less distortion, although I'm not sure of that either. But this technology is still developing, and quite fast, so in ten years or so a digital pinhole camera might produce good results. Actually, as cameras will get cheaper and better, I think we're going to be completely surrounded by cameras in the future, and with the images put in the internet that would create some sort of Big Brother. Except that we are our own Big Brothers, so the effect would be the same, but the intentions different. DirkvdM 06:41, 3 August 2007 (UTC)
 * This is why I ask - according to the ccd article they are 70% photon efficient whereas film is only ~2% efficient - what I need is infomation on sensitivity of charge measuring devices, number of photons I can expect to be incedent on an element in an array etc can anyone help?87.102.36.154 20:38, 3 August 2007 (UTC)


 * Yes, a digital camera can take fast pinhole pictures. For example, in broad daylight, mine'll work with an exposure of 1/60 of a second.  However, there's a major problem: the small sensor size means that the camera will be heavily diffraction limited.  The depth of field is infinite, but that just means everything's equally blurry.  See  for an example. --Carnildo 22:32, 3 August 2007 (UTC)

Short term Memory
how can short term memory be erased without affecting the brain ? can this happen??


 * Memory is stored in the brain, so you can't erase memory without affecting the brain. Maybe you meant to say "...without risk of permanent brain damage?" or something like that? I still think the answer's definitely "no". —Keenan Pepper 20:22, 2 August 2007 (UTC)


 * Short-term memory gets 'erased' automatically&mdash;most theories of memory tend to hold that information in short-term memory lasts less than a minute. There are a number of disorders, injuries, and drugs that can affect the way that information is transferred from short-term memory to long-term memory for extended storage.  Are you interested in anterograde amnesia, in which a person has functional short-term memory but can no longer form new memories?  Our article lists a number of causes. TenOfAllTrades(talk) 21:13, 2 August 2007 (UTC)


 * (edit)Surgeons/anthesiologists often give a patient Versed, a drug which erases short term memory for the pre-operation period, before giving the patient a paralyzing agent of the curare family which prevents breathing, after which they stick a breathing tube in the windpipe. It is a convenient tool to prevent the patient remembering a most unpleasant experience. Versed, like Rohypnol, can be used as a "date rape" drug, but it is legal for physicians in the US to administer it. Some patients have complained of memory loss which interferes with their ability to do a technical job after the Versed use during surgery, and have complained that they were not told the drug would be used, and that they were just told it was "something to relax you" rather than an amnesiac drug, to which they would not have consented. There are drugs used in animal experiments which prevent the consolidation of short term memories into long term memories. The two memory systems are believed to have different modes of operation. Edison 23:28, 2 August 2007 (UTC)


 * I believe the best analogy (and how the brain actually works) is that short term memory is like the software in the memory of your computer - recirculating electrical charges - if you turn the computer off and on again - everything is wiped out. Long term memory is more like rewiring the brain - forming new, physical connections between neurons.  If you were to rewire your computer in order to make it do something new - then turning it off and on again wouldn't change that.  SteveBaker 00:07, 3 August 2007 (UTC)

Animala
Are being a vertebrate and carnivorous characteristics of animals? 172.142.215.130 20:55, 2 August 2007 (UTC)
 * See Animal. Vertebrates are a subphylum of chordates (a major grouping of animals). There are carnivorous animals throughout the animal kingdom, many of which (e.g. many insects) are not vertebrates. Flyguy649 talk contribs 21:02, 2 August 2007 (UTC)


 * And butterflies, for example, are not carnivorous. Plant eaters are herbivorous.  --Bowlhover 21:23, 2 August 2007 (UTC)


 * Well, yes, the question is poorly worded, the answer: YES, "vertebrate" and "carnivorous" are indeed characteristics of animas. Assuming also not exclusive of their antonyms "herbivore" and "invertebrate", as the above points out.. Vespine 22:49, 2 August 2007 (UTC)

All verterbrates are animals. but an organism can be carnivorous without being an animal. See Carnivorous plant and Carnivorous fungus. Depending on your definitions, there are also carnivores in the other three Kingdoms. -Arch dude 00:56, 3 August 2007 (UTC)

Copper Pipe
What is the difference between Type L and Type M copper pipe? Their uses, etc... LCecere 21:13, 2 August 2007 (UTC)


 * Type M (red stripe) is standard. Type L (blue stripe) is heavy-duty, with a substantially thicker wall.  There are also types DWV (yellow stripe) which is thinner and for unpressurized drainage use only, and type K (green stripe) which is even heavier duty than L.


 * The outer diameters of all four types are the same, so you can use the same fittings for any type of pipe. (Though in the larger sizes, there are also lighter-duty, non-pressure-rated fittings for drainage use only).


 * Me, even though I'm usually one to spend extra money on "the best", I use type M for just about everything. It really is seems to me to be good enough for ordinary use, and it's substantially cheaper (2/3 or 1/2 the price of type L). I have used type L only (a) where there was some danger of freezing, and I hoped the heavier-duty tubing would be more resistant to bursting, and (b) where I wanted a more rigid, self-supporting installation that was more resistant to incidental mechanical stress.


 * (True story: I was doing some plumbing just last night, which involved reworking some existing work which happened to have been done using type L, and it was significantly harder to cut; in fact it was a royal pain. So maybe that's a factor to consider, too. )


 * I believe that type L (and presumably type K) is also intended to be used where the pressure of the fluid (or gas) being carried inside the pipe is substantially higher.


 * (Disclaimer: I am not a formally trained or professional plumber; most of this post has more than a whiff of the dread OR.) —Steve Summit (talk) 23:23, 2 August 2007 (UTC)


 * Steve, I think you may have a problem. I just chased through a whole bunch of overlapping and unorganized articles and found Domestic water system which has a sectin on copper pipes/tubes (same thing). It says you are not supposed to use type M for typical pressure applications. -Arch dude 00:46, 3 August 2007 (UTC)


 * Huh. Thanks for the pointer; I can't argue with that.  (One of the things I'm not trained on is the plumbing code.)  I don't know how widespread misuse of type M tubing is, but I suspect I'm not alone. —Steve Summit (talk) 01:20, 3 August 2007 (UTC)


 * Our article isn't correct on that point, or at least it lacks detail. Many (indeed, perhaps even most) North American jurisdictions permit Type M hard copper lines for aboveground residential applications.  (Just ask the Copper Development Association.)  Check your local building code for rules and regulations, and remember that your insurance company likely won't cover you for water damage caused by plumbing that's not up to code. TenOfAllTrades(talk) 03:21, 3 August 2007 (UTC)


 * Thanks for that link to http://www.copper.org/, Ten. There's a bunch of information in there I'd been meaning to look for.  And User:LCecere might well find some answers there, too. —Steve Summit (talk) 23:43, 3 August 2007 (UTC)

What is the name of the 'no money - binge reflex'?
Whenever I run out of money, ie I have say less than $10 until payday, I almost always have a strong urge to buy high fat / carbohydrate food (bread, cookies, fried food etc), even if I am not short of healthy food. What is the name of this reflex? I assume it's been documented. Mjm1964 22:36, 2 August 2007 (UTC)


 * I don't know if it has a name, but I guess the cause is your brain concluding "winter is coming" and decides you should be spending that money on cheeseburgers to store fat for the lean times ahead, rather than frittering it away on DVDs. If there's no term let's coin one : "psychological winter". -- Finlay McWalter | Talk 22:53, 2 August 2007 (UTC)


 * It reminds me of the film 1984, the young boy Winston is with his family and they are starving. They have some food (chocolate I think) to share.  He takes it all and runs off.  When he comes back later they are gone.  I think the reflex has evolved because in times of great starvation, someone steals the last of the food.  That person survives, and passes on the genes for that behaviour.  The rest die.  Mjm1964 23:04, 2 August 2007 (UTC)


 * Surely just old Darwinism? Survival of the fittest (or greediest/most indulgent) EMMA 15:13, 3 August 2007 (UTC)
 * Na! Its called survival of the fattest!--88.111.76.83 22:02, 3 August 2007 (UTC)