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[edit] Currency

Is the serial number of US currency machine readable yet? ...IMHO (Talk) 03:35, 20 June 2006 (UTC)

Is there any reason to suspect that the serial numbers are not readable by optical character recognition? I think the answer is obvious.
Should be. I saw a bit on the History Channel tonight noting the Fed having automated systems to detect superbills mixed in with legit $100 bills. — Lomn | Talk 04:49, 20 June 2006 (UTC)
Actually I am thinking more in terms of a device anyone might carry in their pocket similar to a battery powered credit card reader. ...IMHO (Talk) 08:00, 20 June 2006 (UTC)
Well, the technology certainly exists. You'd basically be doing OCR on a specific location with a roll-through scanner, and that can be done. I don't know that anybody has actually created a product, though. — Lomn | Talk 17:22, 20 June 2006 (UTC)
I don't believe such a machine would be effective in detecting forged notes. There are simple (and cheap) devices that help in that, the most common example being this ultraviolet light thing which shows small coloured strands in the note (I don't know if that applies to US currency). Compared to the other security features like this, the hologram, the metallic stripe in which you can read the minute text and the sign that fits perfectly if you hold it towards light, the watermark, etc, I believe the serial number wouldn't be too difficult to forge. Also, as new banknotes get printed all the time, to decide if the note is valid, the data in device would have to be updated frequently or have a continuous link to some central server. (Also, if you wanted a machine-readable serial number, it would probably better to use some kind of bar code.) – b_jonas 10:55, 23 June 2006 (UTC)

[edit] Stupid question

In what way is it justifiable to allow stupid people to vote, hold positions of power, etc.? By this I mean logically, as it's obvious that nearly every country's constitution gives them this right, and it is in every way illegal to exclude them of this right.  freshofftheufoΓΛĿЌ  04:15, 20 June 2006 (UTC)

Um... who decides who's "stupid"? —Keenan Pepper 04:30, 20 June 2006 (UTC)
Well that wasn't the question. In fact, I deliberately avoided that question.  freshofftheufoΓΛĿЌ  04:36, 20 June 2006 (UTC)
Assuming that "stupid" means they are not able to hold a position of power in a responsible manner, I don't believe they would be voted into that position. Appointed, perhaps. As for voting, I don't see why "stupid" people shouldn't be allowed to vote, unless they do not understand what a vote is or what the voting process means. --M1ss1ontomars2k4 (T | C | @) 04:48, 20 June 2006 (UTC)
Of course, "who is stupid" is the core question, avoided or not. Find an objective unambiguous means of defining "stupid" and you've then got a position to argue from (analagous to how many US states deny the right to vote to convicted criminals). Otherwise you've just got a regime masquerading as democracy. — Lomn | Talk 04:52, 20 June 2006 (UTC)
Intelligence is hardly the only criterion that makes somebody suitable for a leadership position. To take a simple example, the senior staff at Long Term Capital Management were extremely smart people. Didn't stop them losing an enormous pile of money through overconfidence in their own abilities. However, I think I'd expect my elected representatives to have a certain level of intelligence and intellectual curiosity. --Robert Merkel 05:09, 20 June 2006 (UTC)
People are not stupid; they are loyal to their politicians.
People are not gullible; they are ...
In a model two-party democracy, both parties offer capable and wise candidates. Even a moron can vote.
In the real world screwball democracy, ...
Anyway, democracy abhores disfranchising voters. Some countries allow criminals to be disfranchised. Some others are even afraid to do so. Making mistakes now is not the end of the world. There will be future generations to pay for our mistakes. This is democracy. -- Toytoy 07:19, 20 June 2006 (UTC)
Stupid people are idiots. The word idiot is derived from the greek idiotes meaning a private individual who doesn't participate in politics or public life. Given that in the UK almost half the people don't bother to vote, with similar figures in most other democracies, it is the case that stupid people don't vote (we can tell they're stupid because they don't vote). If they're not going to vote anyway it isn't really necessary (& could be counter productive) to actually legally prevent them from voting. AllanHainey 08:09, 20 June 2006 (UTC)

Many smart people do not vote anyway. Why you ask? They know that elected officials are the go-betweens. Go-betweens are the people who represent the bureaucracy to the public and the public to the bureaucracy. For this reason the stupidity or lack thereof among elected officials is virtually nullified. ...IMHO (Talk) 08:08, 20 June 2006 (UTC)

The other reason why smart people don't vote is that they can not decide which stupid one to vote for. - Wikicheng 08:33, 20 June 2006 (UTC)
Depending on who you think are the stupid people, they are possibly the most likely type of people to vote.
Let me try something else: If I set the definition of stupid as a "person who has a low ability to make correct, logical decisions independently in a variety of situations" does that work better? I'm curious about M1ss1ontom's opinion. And as for Lomn's comment, I believe most certainly that it is possible to argue without a position on "stupid", just like you can argue about the existance of God whether you believe or not. You just have to allow some assumptions.  freshofftheufoΓΛĿЌ  09:58, 20 June 2006 (UTC)
It's not whether you believe or not -- I believe some people are stupid -- but whether you can create any meaningful basis for discussion. To use your example, most discussions as to whether God exists understand that they're discussing an omnipotent supernatural being, not just some lame superhero like Aquaman. A useful discussion about God is impractical if one of the parties is instead arguing the existence of his dog.
Therefore, without some standard, all you're asking the ref desk is whether or not we think it's a good idea for you to dictate who votes, and the core point is that when an arbitrary standard is sued to select voters, the actual power lies only with the people who set the standard. — Lomn | Talk 14:23, 20 June 2006 (UTC)
As an additional note, "stupid" is a particularly vague term. It's possible to debate political vagaries (say, is it right to tax the rich more than the poor) so long as at least an objective comparison is understood -- a rich person makes more money than a poor one, in tax terms -- even if the precise boundaries aren't defined (how much income constitutes "rich"). However, what's the measuring stick for "stupid" vs "smart"? — Lomn | Talk 14:27, 20 June 2006 (UTC)
Well, I don't know about stupid people, but if you want to exclude particular groups from democracy based on character traits, how about selfish, or lazy, or greedy, or racist, or not policitally correct? Would you rather your representative was stupid or greedy? Stupid or racist? Where does it stop? The particular problem with excluding people from democracy in large numbers is that they are likely to be upset; if you exclude enough you have the potential for unrest or revolution. The general problem in all these cases is making a definition, because in practical terms you couldn't propose a real action or estimate effects until you make a definition of the term. Notinasnaid 12:53, 20 June 2006 (UTC)
The thing is, I never suggested that they shouldn't be allowed. I was actually asking why they should be.  freshofftheufoΓΛĿЌ  16:53, 20 June 2006 (UTC)
Do you see how that's a loaded question suggesting that they shouldn't be, though? Anyway, to try to answer the original question: stupid people should be able to vote because no one has presented a coherent objective case as to why they shouldn't, and modern liberal democracies generally agree that elective rights are restricted primarily by age and citizenship. — Lomn | Talk 17:24, 20 June 2006 (UTC)
Women decided to prove they were no more idiots in the beginning of the last century. Before, only rich and educated people did vote - as in Athens.
Each time politicians allowed some groups to vote, thet did so because they hoped they would gain more votes than the other party. What if pets and IA machines were allowed to help us choosing ? --DLL 20:49, 20 June 2006 (UTC)
I suspect you're talking about the USA. Women have had the vote continuously since 1893 in New Zealand and 1894 in South Australia. JackofOz 09:25, 22 June 2006 (UTC)

In case you're interested, the kind of government you propose, where intelligence forms a primary criterion for voting/governence, is called a geniocracy. GeeJo (t)⁄(c) • 23:00, 20 June 2006 (UTC)

At elections, everyone hears from the television how many people have voted and more importantly, how many had the right to vote. Thus, if stupid people weren't allowed to vote, it would get out very soon that there are so many stupid pepole in the country or state. I believe this would have a bad impact on people's mood, especially if they started to compare figures from all the regions. People would be discriminated just because they come from a region where fewer people can vote. – b_jonas 10:48, 23 June 2006 (UTC)

[edit] =Do you suffer from short-term memory loss? - I don't remember

Hi, I've looked at Short term memory, working memory & amnesia but I can't find what I'm looking for. Does anyone know if there is a condition which renders someone unable, or makes it harder to, remember regular or irregularly recurring events once they've happened once. For example something that would make it harder for someone to remember to renew a monthly bus season ticket after she had bought the ticket the first time; or which made it harder to remember to pay regular council tax bills?

I realise that there may not be a name for this other than "forgetfullness" or "disorganised" but if there is a specific condition or conditions which could have this effect could you please let me know.

Thanks AllanHainey 07:55, 20 June 2006 (UTC)

I guess we would have to know the rest of the person's story. Many different things, from anterograde amnesia to dementia/delirium to depression can all cause the symptoms you describe. The key is to know what else is going on and what the rest of the brain is capable of doing! InvictaHOG 10:45, 20 June 2006 (UTC)
I hope this doesn't come over as flippant, but it just sounds like a perfectly normal pattern. At least in my experience. The first time you have to pay that bill, it will pray on my mind until it is done. After that, it's impossible for me to hold in my head that it needs doing over and over. What you need is not a better memory, but better organisation. It's hard, and I'm bad at it, but a key thing is not to have lots of places to check: just one master list of things to do. Then you only have to remember to check the list once a week, and have the discipline to both check and act. Notinasnaid 10:53, 20 June 2006 (UTC)
What was the question ? --DLL 20:50, 20 June 2006 (UTC)

[edit] Medicine

What does the "C" stand for in vitamin C?

Apparently nothing. I thought it might be citrus but it appears to have been used because it's the letter after B (or possibly because it simply wasn't taken yet).  freshofftheufoΓΛĿЌ  10:05, 20 June 2006 (UTC)
  • Like many things in science, I think this was just convenient naming. A, B, C, D.... - Mgm|(talk) 12:50, 20 June 2006 (UTC)
What about Vitamin K? Why was it named so? (Assuming that vitamin K actually exists, I am not too good in biology) Jayant,17 Years, India • contribs 13:09, 20 June 2006 (UTC)
K = koagulation. The MadSci Network has answered this. –Mysid(t) 13:12, 20 June 2006 (UTC)
It is named because it was derived from and added features to B. C++ added classes, templates, etc, by Bjerne Stroupguard. (Object oriented, etc). There's no "D" derived from "C", though, to whoever said thait.
He was talking about vitamins not Object oriented programming languages.;-) Jayant,17 Years, India • contribs 20:23, 20 June 2006 (UTC)
Maybe some emoticons are just to be supposed in most part of these pages ;-). --DLL 20:42, 20 June 2006 (UTC)
I wonder why nobody pointed to vitamin. This has some info -- Wikicheng 09:35, 21 June 2006 (UTC)
Vitamin S makes you sick, and Vitamin H makes you grow horns on the top of your head. -- Chuq 03:11, 26 June 2006 (UTC)

[edit] electricity in sea water

Hi, Its simple but i have this in mind for long time.. In rainy season,in road side some transformer may get burst and the wires get fallen in rain water,so the people who are all walking in settled rain water get shocked. My question is like the same thing, if some transformer or current giving thing get fallen in sea water,what about the flow of current in the water?Is the whole water get current?If people swim in sea hat happende to them?

  • They get electrocuted if they touch conducting material or are swimming closely to the source of the shock. But the farther away they are the less likely they are to get a shock because the available current would either spread or go through to the ground. The first would spread it over such a large area it's no longer dangerous, the second would mean it's gone in seconds. - Mgm|(talk) 12:48, 20 June 2006 (UTC)
  • It's an issue even when an electric power transmission cable is torn and falls to the ground. Ground is also a conductor, so the current spreads from the cable in all directions. If you happen to be near you are advised not to make long steps (so that the potential between your feet is not too high) or even to jump on one foot. Conscious 04:38, 21 June 2006 (UTC)

[edit] Another quantum mechanics question

Using the wavefunction derived on Hydrogen-like atom can anyone point me to a page that shows or describes how to calculate (using a quantum mechanical method) the energy of (or energy difference between) quantum states. I was thinking for simplicity of taking the energy when the quantum number (n) tends to infinity as being 'zero' as this seems to approximate totally separate electron and proton. Does this energy correspond to using a semi classical method of using the wavefunction to give propabilty density and using that probabilty density function combined with coloumb potential integrated over all space to give the 'average energy' of a wave-like electron?HappyVR 11:46, 20 June 2006 (UTC)

The purely quantum method is to solve the Schrodinger equation HΨ = E·Ψ, where the resulting eigenvalues E are the energy levels of each orbital. For some reason, we have the solutions for Ψ but not for E in the hydrogen-like atom article. Instead, the solution for E is in hydrogen atom. Hope that helps, anyway. (And yes, as you can see, as n goes to infinity, you get to zero potential energy.) To be honest, I haven't tried integrating the probability-weighted potential...I suspect that it ought to give you the right total potential energy, and I'd be concerned if it didn't. TenOfAllTrades(talk) 15:15, 20 June 2006 (UTC)
If you know the wave function, energy is just HΨ/Ψ, indeed (and it's constant if you have the right wavefunction). For your second question, quasiclassical approximation is applicable when n >> 1. (Either I don't know the correct English term or we should have an article on this.) Conscious 04:34, 21 June 2006 (UTC)

[edit] Cutting animals in half?

Could someone be kind enough to satisfy my curiosity and post a list of animals which can be cut into two (or more) pieces and survive, with each piece growing into a separate creature? Cheers. --Kurt Shaped Box 11:54, 20 June 2006 (UTC)

Are you planning to cut animals in half? That said, the planarian would work nicely. --Zemylat 12:39, 20 June 2006 (UTC)
  • The story that earthworms can regenerate in such a way they form two worms afterwards is an urban legend as this link and various others show. Given the fact such animals would require duplicate organs, I actually doubt any animals can do this. The living part of some animals can regenerate limbs and/or tails, but the cut-off part will never grow into a full animal itself. - Mgm|(talk) 12:44, 20 June 2006 (UTC)

Colonial animals such as sponges and corals. Gdr 12:53, 20 June 2006 (UTC)

... and a species of starfish called Linckia laevigata can grow a new individual from a single severed arm. Gandalf61 12:56, 20 June 2006 (UTC)
(edit conflict) What about starfish? I heard that if you chop off one of their arms, it'll becoming a new starfish. But it could just be an urban myth. Jayant,17 Years, India • contribs 13:02, 20 June 2006 (UTC)
It is true. The starfish has an extraordinary ability to regererate. But for a chopped-off arm to grow a complete new starfish, the arm must be of sufficient size – and, as I've heard, the arm should include at least part of the central disc, too. –Mysid(t) 13:10, 20 June 2006 (UTC)
Then if people can give examples of animals that can regenerate, there must be a full list. --Proficient 22:01, 20 June 2006 (UTC)

I do know that there are certain lizards, that if you grab them by the tail, as a last resort, they'll simply let their tail detach, and grow a new one later. However that's not to say that the tail itself will grow a new lizard! Loomis 22:24, 25 June 2006 (UTC)

...I've heard a sponge can be passed through a sieve and reform, but it is probably not a true 'animal'.

[edit] how does biology affects our life?

how does biology affects our life?

Without it we wouldn't be alive. Perhaps you should read biology and come back with specific questions that you need help with. Dismas|(talk) 13:35, 20 June 2006 (UTC)
Do your own homework, kid.  :-) -Quasipalm 16:01, 20 June 2006 (UTC)

[edit] Jumping from a height?

Is it possible for a human to fall from a height of about 1-5 stories without injury reliably? I'm getting tired of taking the stairs... --Zemylat 13:57, 20 June 2006 (UTC)

That's quite a range... I would think it has a lot to do with the physical condition of the person as well as what they are landing on. Concrete would be much harder than grass, sand, or gravel. I used to jump from a height of about 12-15 feet when I was a kid to escape being beat up by the bigger kids on the playground (they'd chase me to the top of a slide, I'd jump, that would give me a few seconds to get away) but I doubt I could do it very often now without straining something. Dismas|(talk) 14:13, 20 June 2006 (UTC)

And the ground was designed to be fallen upon. Most buildings have wood or concrete floors covered with linoleum or carpeting and falling on them would be very different from falling on loose sand, rubber, or gravel. Emmett5 16:24, 20 June 2006 (UTC)

  • It happened. I even heard about a parachutist that survived a fall when his chute didn't open. But don't count on it being in any way reliable when it comes to not getting injured. - Mgm|(talk) 18:08, 20 June 2006 (UTC)
So I'd say it depends mostly on the material. The height and state of the person are also very important. I would not risk trying it though. --Proficient 22:04, 20 June 2006 (UTC)

If you use the same setup as stuntmen do, and jump into a giant airbag, then yes, you can jump from that height and survive. It is important to land back first, however, to distribute the force evenly. StuRat 00:02, 21 June 2006 (UTC)

The biggest danger in jumping from such heights is broken bones, twisted ankles, that sort of thing. One storey is definitely doable, although I wouldn't recommend it on a regular basis. Two storeys, you run a high risk of broken bones - soft, even ground helps some but not much (although, if you have to jump in an emergency, you probably will survive). Three and above, you run a high risk of death. This is all assuming that you're landing on 'ordinary' materials - a huge airbag (as StuRat said) is a very good surface to land on, even from great heights, but you need to land correctly. You can dive into water from 10-12 m without much danger, but make sure you land feet first and ensure the water is deep enough! — QuantumEleven 09:09, 21 June 2006 (UTC)

[edit] Falling in an elevator

Can we infer then, from StuRats reply, that the best thing to do if being trapped in an elevator which starts falling from the fifth floor, would be to lie down on your back? --62.16.189.71 06:02, 21 June 2006 (UTC)

Not sure about that... but it does suggestion I've wondered about for a while. Say you're trapped in something like an elevator and you can tell exactly when it will hit the ground. A split second before it hits, you jump up in the air. Assuming that the elevator survives intact, are you more likely to be uninjured than if you'd just stood in the elevator or braced yourself for impact? Grutness...wha? 06:19, 21 June 2006 (UTC)
No - this is a myth (see the book Worst Cast Scenario). The upward speed you can create by jumping isn't anywhere near enough to compensate for the speed of the falling elevator. Your best bet to survive in a falling elevator is to try and distribute the force as much as possible by lying on your back or on your stomach, trying not to damage your vital organs. Even then, it's dicey. — QuantumEleven 09:30, 21 June 2006 (UTC)
Guys, you have forgotten weightlessness in a falling elevator. The moment the elevator starts falling, you'll lose your footing and you will be floating in the air, falling along with the elevator. You will not be able to anything (turn / jump up etc), except to wait till the elevator hits the bottom. This is, not considering the shock and panic at that moment -- Wikicheng 10:16, 21 June 2006 (UTC)


I dont understand. You wouldnt be going that fast, so why would you die?


This is one of many of the questions discussed in the (frankly hilarious) book, "Why Girls Can't Throw: And Other Questions You Always Wanted Answered" by Mitchell Symons (ISBN: 0060835184 for the hardback) which is an excellent "toilet-reading" book. Symons comes to similar conclusions to those above, but argues (reasonably convincingly) that your best chances of survival lie in having travelled in a lift where you have fellow passengers who are (preferably) fat. --Dweller 10:21, 21 June 2006 (UTC)
If we assume the elevator isn't quite in free fall due to resistance from the walls of the elevator shaft, then you would have a choice of what to do. While lying on your back is best to reduce the risk of any injury in a mild impact, that's not the case in the elevator. Since you are certain to suffer major injuries, the goal is to just stay alive. I would suggest that standing upright, with the knees slightly bent, would be best. This would allow the legs to fold and then fracture on impact, hopefully protecting the vital organs in the abdomen and head from fatal forces. StuRat 12:32, 21 June 2006 (UTC)
Although, if you were nearly weightless, you could attempt to gather your body into a tight ball spinning at high-speed, and when you landed you would roll around distributing the shock of the fall to all parts of your body. It'd be funny to watch on the CCD after it all ended too.  freshofftheufoΓΛĿЌ  16:24, 21 June 2006 (UTC)
Actually, your best chance is to pinch yourself and wake up, because I don't think an elevator has ever fallen, at least not in the last 100 years. If you look down an elevator shaft, you'll see they have massive cables up the wazoo - way overkill, thankfully. (correct me if I'm wrong about elevators never crashing - i didn't actually research that)--Bmk 21:25, 21 June 2006 (UTC)
Elevators still fall, but due to emergency brakes, nowadays they are usually stopped (relatively) gently before they hit the bottom. But not always. A Google News search on elevator fall turned up this article from today. And here are two recent articles about elevator falls where the emergency brakes stopped the car before it hit bottom. Chuck 21:48, 21 June 2006 (UTC)

Wikicheng, because of friction between the elevator and the tracks you would still have...god some physicist is going to stab me in the face for putting it this way..."some gravity". --mboverload@ 02:38, 22 June 2006 (UTC)

Yes. Agreed :-) -- Wikicheng 08:16, 26 June 2006 (UTC)

Actually, elevators still fall; in fact, I know firsthand what it feels like because I was hurt in a plummeting elevator last month. I'd like to think one could be resourceful enough to lie flat and what have you, but the truth is, it's so violently fast and bone-chillingly shocking that by the time you've remembered your name, you're already in excruciating pain at the bottom of the shaft. Have you imagined the scene in your mind? Well, it's worse than that. To be fair, I didn't fall that much; maybe with 5 or 6 floors you'd have time to scream for a second and a half, as opposed to just feeling your blood go cold before you can say anything. Maybe you could react if you were in a constant state of alert whenever you're in an elevator, but it's the sort of freak accident one never expects. Most people have an instinctive, Pavlovian response to these machines - enter the car, push the button, and up you go...so of course it's likely to catch you utterly unaware (even if you've read guides on how to survive the situation). And bear in mind, I had advance warning - a second or two before it fell, it shakily shuddered to a halt, which gave me time to think, "oh shit, this thing is going to fall", not ponder the physics versus my odds of survival. I don't know, maybe I'm a dim-witted dullard and others would react quickly and resourcefully, but that was my experience. My take on how to survive it is to either bend your knees, or if you have time, lock into a ball, hands over your head. Lying flat may distribute the blow, but the blow is so powerful to begin with that you'd just distribute a massive force that, even divided, would still be strong enough to shatter anything it touches. So if you're flat on your back, you may just end up with a broken spine, shoulders, hip, head, etc. Curling up into a ball might do, but is unlikely with the kind of time you have, coupled with the speed of the car. Look, if you have to break something, it may as well be your foot or leg, just bend your knees to minimize the damage some. It's better off to have plates & screws in there, maybe hobble around on crutches with serious fractures for several months (as in my case), or you may never walk properly again...but consider the alternatives. Brain damage? Quadraplegic? Death? Shattered hip? Take your chances with foot fractures instead...theyre generally easier to heal as well.

[edit] Hairyness and evolution

Male and female primates are both very hairy. What is the evolutionary reason for female humans being so hairless? What is the evolutionary reason for both sexes sprouting armpit hair, but not knee hair? Hairy Dweller 14:10, 20 June 2006 (UTC)

Here is something to consider:
For many decades, the most popular explanation of hairlessness was that humans lost their hair to keep cool. Too much hair made humans—very active apes—hot, like elephants. Elephants evolved huge floppy ears to radiate heat back into their surroundings. But when hominids moved out of the forests and into the savannah, the same task could be carried out by the entire body, thanks to hominids' upright posture (which exposed less skin to the sun) and their lack of hair.
Mark Pagel, at the University of Reading, and Sir Walter Bodmer, at the John Radcliffe Hospital in Oxford, have a new idea. They believe that parasites are the key to human hairlessness. Humans, they say, lost their hair in order to reduce the burden of parasites such as fleas and ticks, some of which would have transmitted disease. Early humans probably lived close together in hunter-gatherer groups, in which the rate of parasite transmission was high. Hairless skin was easier to keep clean. Cultural adaptations, such as the use of fire, shelter and clothing, allowed humans to become furless.
-Quasipalm 16:04, 20 June 2006 (UTC)
Really interesting, but to be harsh, it actually doesn't answer either of the questions I posed. a) why are women less hairy and b) why do we have armpit hair? --16:08, 20 June 2006 (UTC)
The fact that women are less hairy is probably a secondary sex characteristic, and armpit and pubic hair are believed to have remained for reasons of friction and pheromones.  freshofftheufoΓΛĿЌ  16:49, 20 June 2006 (UTC)
Nice. So women are hairless to appear different. Difficult to imagine an evolutionary mechanism for that though. Hairy 'pits reduce friction? Again, I think it would be difficult to demonstrate a survival advantage there. But as a non-scientist, my understanding of evolution is probably as childish as my sense of humour. --Dweller 17:49, 20 June 2006 (UTC)
For the former, many species have different appearances for genders. For the latter, reducing chafing and irritation would seem a clear (albeit minor) survival advantage. — Lomn | Talk 18:12, 20 June 2006 (UTC)
The Naked Ape: A Zoologist's Study of the Human Animal (ISBN 0385334303) by Desmond Morris. Read this, it's fun and sometimes more fun. --DLL 20:39, 20 June 2006 (UTC)
Just my 2 cents. Human Females have a layer of fat just under the skin which males normally do not have. This provides a measure of insulation against the cold which means less body hair is needed to keep warm.
Men have fat under their skin, too, although perhaps less than women. When I cut my arm on a piece of glass, I saw the little yellow fat globules myself. StuRat 23:58, 20 June 2006 (UTC)

Very cool answers. Thank you. Still unconvinced, but enjoying the banter. Also, thanks for proving that scientists can answer questions in plain English. Just wish your cousins on the Mathematics page were able to do so. (Mind you, I brought it on myself) --Dweller 21:19, 20 June 2006 (UTC)

Secondary sex characteristics don't only emerge as ways to differenciate the sexes. One of the only logical explanations why human breasts are so much larger than those of other mammals is that they evolved as an attractive trait. This makes sense because a healthier female (with better access to food) would more likely be able to sustain large breasts and it would be extremely easy for a male to recognize that. You could as well theorize that it is easier for hairless females to show off their health than patchy hairy ones, though that doesn't explain why other animals don't evolve in the same way. It's probably a much more complex combination of factors.  freshofftheufoΓΛĿЌ  05:22, 21 June 2006 (UTC)
  • The "science" is breast augmentation, hair removal, et cetera.Patchouli 05:36, 23 June 2006 (UTC)

Not sure how much this is really backed up by science, but supposedly humans lost hair after the domestication of fire. With an external means of keeping warm at night, hair wasn't necessary and, since hair hosted parasites, became a liability. Hair remained where sweat glands doubled as scent glands and the head, which had more stringent requirements for protection from cold or sun. However, that doesn't explain beards or male pattern baldness... Peter Grey 05:55, 21 June 2006 (UTC)

I have heard something similar, stating that hair disappeared after HS started wearing clothing, probably around the same time that they started using fire, and possibly for the same reasons. Facial hair could be a secondary sex characteristic too, or some similar visual feature.  freshofftheufoΓΛĿЌ  16:19, 21 June 2006 (UTC)
Women do have as much hair as men, it's just much finer. The coarseness of body hair has to do with the timing of introduction and the dosage of male hormones. Read up on Polycystic ovary syndrome, anabolic steroids, Hirsutism, and Sex hormones. A theory for the existence of underarm and groin hair is to trap body scent indicators, for the purpose of reproduction and scent recognition of relatives. Try reading up on Underarm hair and Pubic hair.--Anchoress 20:45, 21 June 2006 (UTC)

[Link causing problems in IE removed]  freshofftheufoΓΛĿЌ  06:47, 25 June 2006 (UTC)

[edit] Circumcision

I just read the circumcision article, but couldn't find any information on how the "string" that runs on the back of the penis is "dealt with". Isn't the "string" some kind of "tube" for urin and semen? How does one avoid not cutting it off when doing a circumcision? Jack Daw 14:46, 20 June 2006 (UTC)

I think you're talking about the frenulum; it's a band of tissue that runs along the bottom of the foreskin...? It is not involved in the passage of urine or semen; all of that happens in the urethra. the frenulum is frequently trimmed or removed during circumcision without ill effect—it only contains some small blood vessels which heal rapidly. TenOfAllTrades(talk) 15:18, 20 June 2006 (UTC)
It's harmless to cut off. --Proficient 22:05, 20 June 2006 (UTC)
Though I wouldn't recommend trying this out for yourself... GeeJo (t)⁄(c) • 23:10, 20 June 2006 (UTC)
I wonder whether the word "harmless" is appropriate for this procedure. I think that it is more correct to say that the dissection of the frenulum is a normal part of cicumcision, which typically does not produce immediate or long-term physical harm.Tuckerekcut 23:44, 20 June 2006 (UTC)
Nota bene: There is a small but noisy contingent of people who have very strong opinions about circumcision, either pro or con. Be careful about circumcision info you find on the web. A lot of it is provided by such people, so stick to very reputable sources. --George 04:16, 21 June 2006 (UTC)
Interesting comment, George. Are you saying that someone with a very strong opinion one way or the other, about this or any other subject, is ipso facto out of contention as "very reputable"? Does your own post above count as a "strong opinion", and does that make your proferred advice not very reputable? JackofOz 09:12, 22 June 2006 (UTC)
Far more importantly, does a contribution from an editor named George mean that there are indeed two editors, one named "George" and the other named "Geogre"?
As for myself, I have a very strong opinion, "pro" circumcision, for cultural reasons. I suppose that makes me part of a small and noisy contingent, and also not very reputable. Oh well, I've been called worse. I see you've found a new toy, Jack. The very tiny writing thing. Have fun! Loomis 22:32, 26 June 2006 (UTC)

[edit] Texas Instruments subfamily abbreviations

Hi all. I'm trying to figure out what some Texas Instruments IC subfamily abbreviations stand for. For example, I know that LS stands for "Low power Schottky". I want to know what other abbreviations stand for, such as NE, SA and SE (specifically for the 555 timer). Thanks! ~MDD4696 16:19, 20 June 2006 (UTC)

Actually, I believe the NE, SA and SE abbreviations belong to Fairchild Semiconductor... but I still have no idea what they mean! Perhaps they're just random.... ~MDD4696 18:50, 20 June 2006 (UTC)
Signetics, according to 555 timer IC. Data sheets like this STM one say that those three prefixes refer to different temperature grades. I can't find out why those particular letters were chosen, though. --Heron 20:13, 20 June 2006 (UTC)

[edit] Ethanol

Do you have any information on how to make ethanol from paper

Thank you Richard--203.109.165.249 22:44, 20 June 2006 (UTC)

The most efficient route would be to add cellulase, typically from symbiotic bacteria from ruminants, which'd break the cellulose to glucose. From there, add yeast in anaerobic conditions to produce ethanol GeeJo (t)⁄(c) • 23:18, 20 June 2006 (UTC)

[edit] Microsoft Outlook Problem

When I type the word products in an Outlook e-mail message, pr appears on the first line and oducts jumps to the second line. How can I fix this?Patchouli 23:26, 20 June 2006 (UTC)

It could be an autocorrect problem. Try clicking the 'undo' button right after. If that fixes it (shows products correctly), someone's played a joke on you and added an autororrect to Word, which you can correct in word.--Anchoress 23:29, 20 June 2006 (UTC)
  • I sent the e-mail. Now when I look at the e-mail in the Sent Items folder, the word products is not disconnected and appears whole.
Use AutoCorrect when Word isn't the e-mail editor check box is currently selected. Should I deselect it?Patchouli 23:55, 20 June 2006 (UTC)
Well if the email looks fine now, it probably wasn't an autocorrect problem. Sometimes, either because of refresh problems, font size/paragraph alignment etc, words will appear to break across lines. Of paramount importance is whether or not it ever was apparant that the text was broken across lines in your unsent message? Did you check? Because if it was, you'll have to wait until it happens again and investigate further. If it wasn't, then it's just a failure of WYSIWYG and can be ignored. As for the Autocorrect, don't change anything unless or until you know for sure it's a problem.--Anchoress 12:48, 21 June 2006 (UTC)