Wikipedia:Reference desk/Archives/Science/2006 December 6

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[edit] December 6

[edit] Discworld's sun

This is a better question than my one about toothpaste... I think. This will involve making a bunch of assumptions. If the Discworld's sun is 80 miles in diameter, and the surface of the sun gives out as much light as our Sun does per square metre or what-have-you, and assuming you are observing the Discworld's surface at a point where the sun is directly above, how far would the sun have to be from the ground you're observing in order for it (the ground) to receive exactly the same amount of light a point directly below the Sun (pointing directly at the Sun?) on Earth gets? I'm confident there's a caveat somewhere that makes this unanswerable, and I'm kinda tired so my prose might be confusing, but it's worth asking, right? Vitriol 01:11, 6 December 2006 (UTC)

The sun has to have the same angular size in the sky, so take the radius of the earth's orbit and scale it down by the ratio of sum sun diameters. That ought to do it. Melchoir 01:25, 6 December 2006 (UTC)
I don't think I even know what that means. Vitriol 01:27, 6 December 2006 (UTC)
Which part? Maybe Angular diameter helps? Melchoir 01:30, 6 December 2006 (UTC)
There should be a sense of futility about trying to help a 15-year-old up at 1:35am with no formal maths education beyond year 8 (what's that in America? I'm English) figure it out himself. Save yourself! Vitriol 01:35, 6 December 2006 (UTC)
Translation: If Discworld's sun is a bazillion times smaller, it has to be a bazillion times closer. Clarityfiend 01:51, 6 December 2006 (UTC)
So I got to find the diameter of the Sun, and then... I guess I'll think about this tomorrow. Someone remind me. Vitriol 01:53, 6 December 2006 (UTC)
Cool. Don't worry, you already know all the maths you'll need. I, or someone else here, can help you with setting up the equation if you want. Melchoir 02:00, 6 December 2006 (UTC)
Let's see, assuming this sun is a G class main sequence star, 128.72 km is .00925 percent of the 1,392,000 km diameter of the Sun... 0.096176 AU or 14,387,860 kilometers. Roughly a tenth the distance that the Earth is at now.
I have a microsoft excel file that I used to figure this kind of stuff out. I don't remember all the equations necessary, but I'm sure the inverse square law factors in somewhere. Ƶ§œš¹ [aɪm ˈfɻɛ̃ⁿdˡi] 08:10, 6 December 2006 (UTC)
Unfotunately the answer is miles out.

ok Suns diameter is 139200 km (1mile=1.6093km) so suns diameter = 864972miles . Discworlds sun is 80miles there for sun is 10812 times wider - so the surface area is 10812x10812 times more = ~117x106 times more. There is an inverse square law to distance meaning the discworld sun will need to be 10812 times nearer.. Suns distance is 92.95 million miles so discworld sun will need to be 92,950,000/10812 = 8600miles away. Does that match what Terry Pratchett says?83.100.138.168 09:28, 6 December 2006 (UTC)

I don't think he's said. I tried to figure it out, but then I got stuck and confused because Excel and Google gave me things like 3.5475926*10^6 (that's just an example) which I couldn't remember how to figure out, so I gave up. Vitriol 13:45, 6 December 2006 (UTC)
I wouldn't be surprised if Pratchett has worked this stuff out. Have you ever seen the Science of Discworld book(s)? You can't find them in the US, because we hate science, but I believe they're printed everywhere else. Melchoir 18:58, 6 December 2006 (UTC)
I agree with 83.100.138.168; it should be 8600 miles. Aeusoes1: I think you meant 14 387.860 km instead of 14,387,860 km, right? --Bowlhover 01:45, 7 December 2006 (UTC)
I didn't, but my math could be wrong somehow. I'm only wrong by three places. Ƶ§œš¹ [aɪm ˈfɻɛ̃ⁿdˡi] 00:48, 8 December 2006 (UTC)
The Science of Discworld books don't have anything to do with this sort of thing. 80.169.64.22 17:05, 7 December 2006 (UTC)

[edit] protien

is milk protien broken during cooking tea?

Overheard conversation: I tell you, he's a complete fool in the kitchen. He can't cook tea without braking the protein! ;-) —Bromskloss 14:21, 6 December 2006 (UTC)
This is only a partial answer; hopefully someone can clarify. I doubt they're broken, but the probably do undergo denaturation... although I suppose it depends on the specific protein and the heat of the tea. -- SCZenz 17:18, 6 December 2006 (UTC)
Peptide bonds will not hydrolyse to a significant extent with a short, aqueous boiling treatment at atmospheric pressure. ike9898 17:50, 6 December 2006 (UTC)
Even if peptide bonds did break, the amino acids are still intact and ready to be absorbed and put to good use, right?
Many conditions that are sufficient to hydrolyzed peptide bonds will simultaneously destroy certain amino acids to a greater or lesser degree (BTW this makes accurate amino acid analysis quite difficult). There are also other possible reasons to care whether or not a protein is broken down. For example, hydrolyzed protein can be very bitter; not something you'd want in your tea. Hydrolysis can also alter a protien's 'functional properties; for example, it's ability to stabilize an emulsion. ike9898 20:39, 6 December 2006 (UTC)
Thanks for this info. Username132 (talk) 23:29, 8 December 2006 (UTC)

[edit] Wikipedia

How many servers does wikipedia have? total? and how much CO2 is produced by the operation of each server? IE. How much electricity has to be produced via fossil fuels to power wikipedia for a period of 1 month? Should wikipedia be subject to some sort of "CO2 Tax"?13:47, 6 December 2006 (UTC)13:47, 6 December 2006 (UTC)172.145.152.76

Hehe, are you picking a fight? :-) How many servers and how much electrical energy? I don't know, probably somone else does. Even then, it might be difficult to say how much of it comes from fossil fuels. Tax? Probably not any more than for your own energy consumption (in proportion to how much you use, of course). —Bromskloss 14:14, 6 December 2006 (UTC)
Info on Wikimedia's servers is available here. --24.147.86.187 14:19, 6 December 2006 (UTC)
Many electric utilities have on their webpages a breakdown for the previous 12 months as to how much of their energy was produced by fossil fuels (oil, coal, natural gas), how much by nuclear, how much by hydro, and how much by solar, wind, etc. Some allow customers to pay extra to buy only green power. All the electricity is of course actually mixed together and fungible. The question is answerable. If the servers are separately metered, I could give an approximate answer if I knew the annual or monthly kilowatt hour usage. The air conditioning would need to be added, since they would overheat and shut down if not cooled, as well as the lighting and other necessary usage devoted to their operation. If they are in a dedicated facility, someone must be paying the electric bill. The nameplate rating on a computer is usually way above the actual usage, as it allows for startup load or worst case load. Edison 15:17, 6 December 2006 (UTC)
On the merits of a CO2 tax on Wikipedia, if such a tax were to be introduced, it would be most economically efficient to apply it to all CO2 emissions equally. That way, the lowest-cost ways to reduce CO2 emissions will be taken. Hypothetically, the Wikimedia Foundation might choose to switch to more expensive but more power-efficient servers, for instance, in response to higher power costs, or might choose to source their power from a non-emitting source. Or it might be cheaper to simply pay the tax - other people who can cut their emissions more cheaply will do so instead. --Robert Merkel 05:41, 7 December 2006 (UTC)
Wikipedia uses as much servers as users visits , if no users no servers / alot of users alot of servers . So taxes must go to users ? —The preceding unsigned comment was added by 62.38.241.148 (talk) 22:13, 19 December 2006 (UTC).

[edit] Old men with young hair

In Europe there are several politicians, like John Prescott, Silvio Berlusconi, and the german bloke whose name I cannot remember, who are quite old yet their hair has still not turned grey. John Prescott, for example, is 68 years old and yet he still has brown hair. The other two have black hair.

Could this be natural, or must it be the case that they dye it? What are the oldest, youngest, and average ages at which men's hair turns grey please? 81.104.12.23 15:44, 6 December 2006 (UTC)

I'd guess Grecian Formula. Politicians often have rather large sense of personal vanity.
Atlant 17:07, 6 December 2006 (UTC)

Helmut Schröder sued a newspaper, because they said things like dye or unnatural! So be careful!--Stone 17:18, 6 December 2006 (UTC)

You mean Gerhard Schröder :) Jack Daw 22:07, 7 December 2006 (UTC)

It's something to do with good food and fresh air and healthy relationships. Theavatar3 18:23, 6 December 2006 (UTC)

Prescott certainly enjoys a lot of good food. A lot of food in general, really. GeeJo (t)(c) • 18:31, 6 December 2006 (UTC)
Berlusconi is often mocked in Italian TV shows etc. as wearing a toupee or (more plausibly) for undergoing hair transplantation. Who knows… In a recent TV debate with Diliberto (http://www.repubblica.it/2006/c/sezioni/politica/versoelezioni35/berludili/berludili.html) there was the following brief dialog:
- host (E. Mentana): Ten years later [alluding to the 1996 Berlusconi-Prodi debate] I'm the only one with grey hair
- Berlusconi: I'll give you a good address, the more so because it's your duty to do something about it
- Diliberto: If we are going to talk about hair…
Not only. My great-grandmother was over 70 and she still had natural dark brown hair. And she wasn't living in very bright conditions for most of her life. --V. Szabolcs 15:44, 11 December 2006 (UTC)

Ronald Reagan also had dark hair far enough into old age for it to be unlikely to have been natural. StuRat 12:54, 7 December 2006 (UTC)

[edit] Optional body parts

Last year, I ended up having my gallbladder removed. When I talked to my brother about it afterwards, he joked, "Are you planning on having any other non-essential body parts taken out?" This made me think that there are some organs that people have removed quite regularly and don't seem to have much of a negative affect on them afterwards. Besides the gallbladder, examples include tonsils and the appendix. I know that all of these organs have functions, but apparently, the body can get by just fine without them. So, what other bodily organs can be removed without much of a noticeable effect on a person's body? By this, I mean that the person must not usually be dependent upon drugs or other regular medical treatment after the organ is removed, and the person must not usually experience any significant negative effects from losing the organ after the surgery heals. —Cswrye 15:49, 6 December 2006 (UTC)

You can live without your Spleen and all organs you have two of, like one kidney, or one half of your lung. The rest you you should keep! Your gallbladder is used as storage for gall liquide which is important for digestion, without it fatty meals can give you some trouble. --Stone 15:57, 6 December 2006 (UTC)
Don't forget eyes, ears, tongue, nose, larynx, genitalia and tonsils. Each can be removed without requiring regular treatment after recovery, and your body would continue functioning perceftly adequately, though quality of life would be significantly impaired if they were all removed. GeeJo (t)(c) • 16:19, 6 December 2006 (UTC)
Remembering monty pythons movie, legs and arms are also disposable. Some of yor bones can go too!--Stone 16:47, 6 December 2006 (UTC)
A lot of things can go if you consider death to be only when your brain is shat on. —The preceding unsigned comment was added by 216.164.192.159 (talk • contribs).
Keep in mind that one of my qualifications was "person must not usually experience any significant negative effects from losing the organ after the surgery heals." I would say that most of the things mentioned above would definitely provide some significant negative effects! The spleen and one kidney make sense, although I'm not sure about the lung. From what I've heard, it's possible to live with only one lung, but doing so can lead to some major impairments. —Cswrye 17:32, 6 December 2006 (UTC)
You mentioned "no drugs or treatment". What about replacements, such as a knee or hip replacement? Commonly, those remove part of the body and improve things afterward. --Kainaw (talk) 17:41, 6 December 2006 (UTC)
Hmm...I hadn't thought about that, but I guess that if you need a replacement, the body part wasn't really "optional" in the first place. So for the purposes of my question, replacements don't qualify. Teeth (mentioned below) is also a good one since it is fairly common to remove wisdom teeth, although you could only remove a few teeth before it began having a negative affect on your comfort and ability to chew food. —Cswrye 21:13, 6 December 2006 (UTC)

In my experience, teeth can be optional body parts. The more you lose, though, the less optional they become.

"The thing about control Ari, is that you don't realize how little of it you have until you have none of it at all." -- Malcom McDowell, Entourage.

Theavatar3 18:26, 6 December 2006 (UTC)

How about body fat, not really and organ but still! --Cody.Pope 19:28, 6 December 2006 (UTC)

You can live without a stomach, if you don't mind losing the ability to eat large meals. Laïka 19:47, 6 December 2006 (UTC)
I've read that the two big toes are the only ones that play a significant role in walking, so it's not too bad to lose the other eight. And then of course there's the hair! --Anonymous, 07:19 UTC, December 7. —The preceding unsigned comment was added by 66.96.28.244 (talk) 07:19, 7 December 2006 (UTC).

[edit] value of voltage in power supply

why the value of voltage of the power supply is always a multiple of 11? ex.-110v,220,440v,1100v.

Edison wanted 100v DC for home use. He allowed a 10% variance of 100-110v. Later, when he was able to better control line loss, he standardized it to 110v so you could be sure to get at least 100v. That was all DC. Tesla pushed AC and, apparently, the concept of 110v stuck. Of course, you can't send 110v very far down a line. So, it was stepped up. It is easy to step up/down in multiples, such as a 1-2 step up that changes 110v to 220v, or a 1000-1 step down that changes 110Kv to 110v. So, the reason for multiple is the coils in the step up/down transformers. I don't really know why the 110v standard stuck. --Kainaw (talk) 17:49, 6 December 2006 (UTC)
Thomas Edison used approximately 100 or 110 volts because wire could be insulated to that level easier than at 240, and because fatalities from accidental contact were much less likely at 110 than at over 200. He wanted to avoid low voltage bulbs, because the cost of the enormous copper conductors would have made it financially non-competitive with gas lighting. (Matthew Josephson, "Edison: a biography." McGraw Hill. New York, 1959, p194). Earlier inventors had been content to make a wire glow with large current (say 10 amperes) from a low voltage battery (say 10 volts), without looking at utility scale implementation. 110 is now a standard U.S. voltage at the point of use, that is, at the appliance, but not for the utility. A utility is required by its state commerce commission to provide typically 120v plus or minus 5 % for residential use at the point of interconnection, which is typically the utility meter. To be a low voltage violation, the utility supply would have to be below 114 volts for over 1 minute, to allow for motor startup current and to allow the utility's automatic voltage regulation equipment to respond to changes in load on a line. There is voltage drop within a residence, so 120 volts at the meter may drop to 110 by the time it gets to an air conditioner in the third floor bedroom at the opposite end of the house. When the voltage drops much below 110, there may be problems such as an air conditioner stalling and failing to come on, or a gas range failing to light, or a microwave not working, or a TV picture pulling in from the sides. Utilities may institute brownouts, in which the line voltage is intentionally decreased by several percent, on days when the supply of electricity is inadequate. At the decreased voltage, a resistive load such as a heater or incandescent bulb will automatically draw less energy. A motor load will typically draw more current at reduced voltage, but at an extreme low voltage it will stall and trip the circuit breaker or its own thermal relay, which also reduces the load on the utility. Sometimes increasing the size of the wire from the main panel to an airconditioner, or other motor load is all that is needed to keep it running on low voltage days. For power or other commercial load, 480 volts is a U.S. standard from the utility viewpoint, and typically allows a 10% variation. Various other voltages are standards from a delta-wye supply basis (208 volts phase to phase in a 3 phase system equals 120 volts phase to ground). Appliances or relay coils are sometimes sold on a "one size fits all" basis" so that one device is supposed to work on any voltage from 208 through 240 volts. If it is a range heating element, for instance, it may take an unacceptably long time to heat up at 208 and provide better service at 240 volts. Or a motor or other device it may work even in a 5% brownout if the source is normally 240, but fail to operate on a 5% brownout when the source voltage starts at 208. By being "early adopters" the U.S. was stuck with a voltage which requires more copper in every appliance cord and in wiring, and which does not allow a small kettle to boil the tea water as quickly as in the U.K or other 240 volt countries.Edison 18:33, 6 December 2006 (UTC)

[edit] glassified nuclear waste

Can glassified nuclear waste provide enough thermal energy to be used as a source of heat for distilling water and if so what is the ratio of distilled water to waste? Adaptron 19:13, 6 December 2006 (UTC)

Not sure if it is even hot, but it is called vitrification. X [Mac Davis] (DESK|How's my driving?) 20:29, 6 December 2006 (UTC)
Stealing from the article Nuclear Waste
Long-term storage of radioactive waste requires the stabilization of the waste into a form which will not react, nor degrade, for extended periods of time. One way to do this is through vitrification. Currently at Sellafield, the high-level waste (PUREX first cycle raffinate) is mixed with sugar and then calcined. Calcination involves passing the waste through a heated, rotating tube. The purposes of calcination are to evaporate the water from the waste, and de-nitrate the fission products to assist the stability of the glass produced.
The 'Calcine' generated is fed continuously into an induction heated furnace with fragmented glass[6]. The resulting glass is a new subtance in which the waste products are bonded into the glass matrix when it solidifies. This product, as a molten fluid, is poured into stainless steel cylindrical containers ("cylinders") in a batch process. When cooled, the fluid solidifies ("vitrifies") into the glass. Such glass, after being formed, is very highly resistant to water. [7] According to the ITU, it will require about 1 million years for 10% of such glass to dissolve in water.
What I get from this is that even when it is vitrified, some of it will dissolve in water. You probably could not use any water in which vitrified waste has been dumped safely because of radioactive contamination. Since some radioactive decay products are volatile, even if you used the radioactive waste to boil the water, radioactive stuff would get into the air and then into your distilled water. This didn't answer any of you original questions because I don't know how hot radioactive waste gets but you could figure out on average how much glass would dissolve into the impurified water on average into a given period of time. Sifaka talk 21:04, 6 December 2006 (UTC)
What makes you think that water must be in direct contact with vitrified nuclear waste in order to extract the heat produced by the waste? Indirect thermal transfer can be accomplished by any number of inert solid, liquid or gaseous materials in much the same way as in a nuclear power plant where the water used to make the steam to drive the turbines is not the same water that is heated by fission of the nuclear fuel. Perhaps I should have asked what the temperature and enthalpy of the stainless steel containers is once they have been filled with nuclear waste? Adaptron 22:38, 6 December 2006 (UTC)
You are right about that, but you still need to find the answer to your original question about how much heat energy the radioactive material is putting out in order to begin to figure out how much heat energy would be transfered to the water. I afraid I have no idea in the least. Sifaka talk 23:04, 6 December 2006 (UTC)
I recall reading somewhere that the waste maintains a high temperature of around 800 deg. F (don't think it was deg. C) for a very long time. Adaptron 05:01, 7 December 2006 (UTC)
I can't find the initial temperature but it is supposed to be down to 100 C after oinly 1000 years.[1] Rmhermen 02:47, 8 December 2006 (UTC)

[edit] Salting the earth

Hi,

just curious about this: why salting the earth makes it infertile? —Gennaro Prota•Talk 20:00, 6 December 2006 (UTC)

Too high a salt concentration kills plants. If the soil is more salty than that toxic level...infertile. There's some info scattered in the text and footnote refs on this page I found by chasing a few wikilinks from your starting point. DMacks 20:09, 6 December 2006 (UTC)
And salt kills plants by sucking out water from their roots, dehydrating them. See osmosis; basically, since the concentration of water is less in salt water then in pure water, the water in the plant's cells will move out. --Bowlhover 20:31, 6 December 2006 (UTC)
Thank you very much to both of you! I had a feeling it had to do with water but wasn't sure exactly how. Incidentally, I'm glad to see that the article about osmosis is quite above the average level :-) —Gennaro Prota•Talk 23:22, 6 December 2006 (UTC)
It must have absorbed good info from the various editors. StuRat 12:44, 7 December 2006 (UTC)
... who are the salt of the earth :) JackofOz 01:25, 11 December 2006 (UTC)

[edit] Solar energy

What will happen when solar energy uses the sun up?

See Sun#Life cycle. —Keenan Pepper 22:06, 6 December 2006 (UTC)

[edit] The Sun

Will man ever walk on the sun?

No its too hot--Light current 22:14, 6 December 2006 (UTC)
And because it is a huge ball of gas and plasma, it doesn't have a surface to walk on anyway - read Sun for more info. Gandalf61 22:58, 6 December 2006 (UTC)
Somewhere towards the middle it must be so dense that a human would be unable to break surface tension or whatever. But yeh, still its impossible. Philc TECI 23:07, 6 December 2006 (UTC)
There's no surface tension because there's no surface, just a gradual density gradient. If you tried to stand on the sun, all the elements of your body would be vaporized and mix with the sun, and then the heavy elements (everything other than hydrogen) would slowly sink all the way down to the core. —Keenan Pepper 01:13, 7 December 2006 (UTC)
A some time in the very distant future, won't the Sun burn out, shrink (possibly after initially expanding) and cool down? Perhaps it would be possible to walk on it then, although by that time humans will either be extinct or have elvolved into something else I imagine. 81.104.12.7 23:42, 6 December 2006 (UTC)
Sure, if you don't mind weighing 276 000 times heavier than you normally do! Something as massive as the Sun (a white dwarf) that's the same size as Earth has very strong gravity at its surface. --Bowlhover 01:34, 7 December 2006 (UTC)
This be from an Ali G watcher, I betcha --24.147.86.187 03:15, 7 December 2006 (UTC)
If the sun were a tad heavier (maybe 35% more), it could theoretically collapse to a Neutron star. Neutron stars have a solid crust, but most emit lethal doses of radiation, and even just lifting your little finger 1 centimetre would require as much energy as 72 climbs of Mount Everest. Laïka 17:45, 7 December 2006 (UTC)

[edit] P.O.E.R.K.W.I.U.

What does P.O.E.R.K.W.I.U. stand for?

Whatever it is it's not something often used. Google had no hits for either that or POERKWIU. Make sure it is spelled right, and if it is, it probably only has meaning to the person who created it. Sifaka talk 00:01, 7 December 2006 (UTC)

Context would help - where was it used? Confusing Manifestation 01:39, 7 December 2006 (UTC)

[edit] Silicon in Diode

Roughly what are the dimensions of the silicon crystal in a diode. Philc TECI 22:18, 6 December 2006 (UTC)

Well it does depend on the type and rating of the diode. See diode closeup--Light current 23:14, 6 December 2006 (UTC)
Would you say 1x1x5mm is a fair guess? Philc TECI 23:51, 6 December 2006 (UTC)
More like 1 * 1 * 0.5 mm and that could be a biggie. Depends on heatsinking etc--Light current 00:02, 7 December 2006 (UTC)
In glass diodes like 1N4148 or 1N34 you can see the semiconductor chunk. --Wjbeaty 08:03, 8 December 2006 (UTC)

[edit] Birth Control

Are the side effects of Necon 7/7/7 and NuvaRing approximately the same? (I've had prescriptions for both, so no worries about the doctor part. I'm just wondering.) 71.220.122.230 23:41, 6 December 2006 (UTC)

Sorry, we don't do medical advice. Try WebMD or ask a doctor. Friday (talk) 00:29, 7 December 2006 (UTC)
It's not advice I'm asking for, I'm just wondering. Your answering of this question affects nothing in my life except fulfilling my curiosity. 71.220.122.230 00:53, 7 December 2006 (UTC)
Not everyone here is a doctor, and therefore not everyone can give factual information. There is a chance that you can be misinformed, and regardless of the use of the knowledge we share, there are liability issues involved. Some times we let small things slip, but questions like yours are best left to qualified professionals. Sorry.--Russoc4 00:57, 7 December 2006 (UTC)
Fine. I just won't ever know. 71.220.122.230 01:00, 7 December 2006 (UTC)
Just ask a doctor, or a local pharmacy, as long as they have "real" pharmacists who know what they are doing. --Russoc4 01:03, 7 December 2006 (UTC)
Boy, are these medical disclaimers annoying. You might have better luck searching the Internet for their detailed patient labeling, which will contain risks and side effects of each. It might also be worthwhile to search Medline (or something similar) to see if they've been compared in a decent randomized controlled trial, which ought to give you a good idea of how they compare head-to-head. --David Iberri (talk) 01:27, 7 December 2006 (UTC)
Thank you, I didn't know about Medline. I'll look there. 71.220.122.230 02:16, 7 December 2006 (UTC)

The Food and Drug Administration website often has good information for drugs, particularly if there was a recent FDA-issued safety warning. Third on the list at this webpage is a 2005 safety labeling change for NuvaRing. The Department of Health and Human Services website is another good source of information; there is a page with some information for the hormone combination in brands such as Necon. --JWSchmidt 03:06, 7 December 2006 (UTC)

Try a PDR, you can find one at a bookstore or maybe a library, or maybe at www.PDR.net. 71.88.110.87 12:04, 7 December 2006 (UTC)

All I can say is that birth control is not a sustainable technique. If you're on it for a decade, say, you're going to notice some poor side effects, and you'd probably deem it best to go off it for at least a few years before going back on again. Mathiemood 06:19, 11 December 2006 (UTC)

[edit] What will humans look like in a billion years time?

Has anyone ever done any serious scientific thinking about what humans will look like in the distant future?

A cynical extrapolation of current trends would suggest that we turn into large balls of fat with vestigial legs but massive sexual characteristics. I hope that won't be true. 81.104.12.7 23:49, 6 December 2006 (UTC)

There is a good chance that humans won't exist anymore as we know ourselves. We could wipe ourselves out, or some natural event could wipe us out, natural selection pressures could have caused us to evolve, or humans could have tampered with their own genome enough so that we become completely unrecognizable. Or we could somehow stay the same... A billion years is a long time, and lots of stuff can happen in it. Sifaka talk 23:58, 6 December 2006 (UTC)

We'd probably just mind transfer ourselves into machines by then. So we could look like anything. ☢ Ҡiff 00:56, 7 December 2006 (UTC)
Oliver Curry says the race will split in two. —Keenan Pepper 01:17, 7 December 2006 (UTC)
Clearly the gnome-guys would be the future of humanity. Vitriol 01:26, 7 December 2006 (UTC)
For the record, lots of people said it before that dufus did. I'm not sure why he got so much attention? Lee Silver actually gave the question real serious thought in his best-selling book Remaking Eden many years ago now. Curry seems like a total moron when it comes to evolutionary thinking in comparison. --24.147.86.187 03:13, 7 December 2006 (UTC)
It would amuse me if that happened, then some natural disaster kills off the frail former upper-class leaving the robust former working-class to evolve and become small, furry, and quadrupedal before another intelligent species emerges and starts exterminating them as pests before keeping some of them as pets and laboratory animals. Vitriol 03:46, 7 December 2006 (UTC)
H.G. Wells came up with the "two species" idea in his 1895 novel The Time Machine - in the far future, the human race has split into the Eloi and the Morlocks. Gandalf61 10:33, 7 December 2006 (UTC)
I go with the BORG idea. There are some chemical and biological process which have taken billions of years to develop naturally that machines might never do as well whereas the ability to see images in every single wavelength of the spectrum including possibly extremely long wavelegths like sound are on the other hand abilities that only man made electronics seem to possess. Adaptron 05:08, 7 December 2006 (UTC)
The timescale you're talking about is just too vast to make any sensible predictions. It's very difficult to predict the advancement of technology a decade in advance. --Robert Merkel 05:32, 7 December 2006 (UTC)
My bet is extinct. After barely three centuries of modern science we've only barely managed to avoid killing ourselves and destroying all usable resources on the planet, and we show no real ability to manage ourselves in the long-term. It seems more likely that someone will come up with a new way and new rationale for killing everyone before then. --140.247.251.173 16:46, 7 December 2006 (UTC)
While I wish I were more optimistic, my guess is "dust" with a scattering of fossils in geologically stable parts of the world. The Fermi paradox is a haunting one: life may well kill itself off wherever it appears, but that's just my dark thought at present time.
There is a fine Arthur C. Clarke novel set a billion years in the future: Against the Fall of Night (wondering if that link will turn blue? I do like Wikipedia after all...) Antandrus (talk) 16:52, 7 December 2006 (UTC)

"What will humans look like in a billion years time?" Very old. —B00P 20:56, 7 December 2006 (UTC)

This question reminds me of a Star Trek Voyager episode in which Tom Paris achieves Warp 10 and as a result achieves infinite velocity (their particles appear at every point of the universe simultaneously). This somehow causes exponential evolution and Captain Janeway and Tom evolve untold billions of years into salamander-like creatures and mate, much to the chagrin of the captain when they 'return' from their paradox. Sandman30s 14:01, 8 December 2006 (UTC)