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September 11

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But why the square head?

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The bizarre Tibetan fox, the pica's nemesis.

But why the square head? --Kjoonlee 00:28, 11 September 2008 (UTC)[reply]

In the article Tibetan Sand Fox, ""The Tibetan Sand Fox has a unique face that appears square; this is an illusion created by its large ruff." So there ya go. Julia Rossi (talk) 08:01, 11 September 2008 (UTC)[reply]

But why the large ruff? --Kjoonlee 19:49, 11 September 2008 (UTC)[reply]
The large ruff is necessary to maintain the illusion of a square head. Wanderer57 (talk) 20:09, 11 September 2008 (UTC)[reply]
A mission shared by Henrik Ibsen and Richard Wagner here[1] among others. Julia Rossi (talk) 22:46, 11 September 2008 (UTC)[reply]

Parrots - mistrustful of humans when nesting...

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Just something that came up in conversation with a friend today. Why is it that a tame female parrot might be perfectly happy to trust you with her life and safety as her owner/companion, yet completely refuse to trust you when it comes to the safety of her eggs and chicks? Yes, even tame hens generally hate it when you go near their nests (say to count eggs or periodically check on the wellbeing of the young) and go into full-on 'angry protective mom' mode... --Kurt Shaped Box (talk) 00:33, 11 September 2008 (UTC)[reply]

This is not confined to parrots. There are many instances of birds developing an extra protective attitude when nesting. Blackbirds, normally timid, can be very aggressive towards anyone who comes too close to their nest, especially when they have nestlings. And swans, while docile and amenable for the rest of the year, can turn into mean critters in the nesting season. Lapwings (green plover, peewit)develop distractive behaviour during nesting to lure away potential predators of its eggs or young. The latter behaviour, while not aggressive, indicates the ability of some birds to alter their behaviour according to the circumstances. This is presumably an instinctive behaviour to protect its progeny. 86.4.187.55 (talk) 06:20, 11 September 2008 (UTC)[reply]
A completely different hypothesis is that they are pretending when you think they trust you. And most of the time, you're anthropomorphizing, anyway, meaning that behaviour in presence of humans all is learned in order to get at food etc. --Ayacop (talk) 07:36, 11 September 2008 (UTC)[reply]
I think anthropomorphism is definitely a big part of the picture. These are birds, not humans, and they aren't very smart. They don't think, "oh, hey, that nice guy feeds me and pets me, so I can trust him with my eggs", because they aren't really thinking in logical chains like that. I mean, parrots are pretty smart birds, but they're only smart by bird standards -- that doesn't mean they're capable of abstract thought. -- Captain Disdain (talk) 08:35, 11 September 2008 (UTC)[reply]
I don't really think that it's anthropomorphizing too much to suggest that a psittacine which remains totally calm and placid when picked up by its owner and cuddled, or rolls over and allows its belly to be scratched, or willingly places its head inside a human mouth to pick food from its owner's teeth (note: don't do this - our mouth bacteria can make birds very ill), or chooses to sleep snuggled up against its owner's head at night 'trusts' (and perhaps even 'likes') that one certain human. Are they smart enough birds to fake all that for the sake of food? --Kurt Shaped Box (talk) 17:31, 11 September 2008 (UTC)[reply]
I'm not saying that they're faking it. That's kind of the point, actually! They just aren't smart enough to make the logical connection that would allow their trust for you to overcome the instinct that tells them to protect their eggs, even though they have genuine affection for you. That kind of thing would require pretty advanced capacity for abstract thought, and they don't have it -- either that, or pretty serious conditioning. -- Captain Disdain (talk) 22:43, 11 September 2008 (UTC)[reply]
I don't think it's confined to birds either. Many mammals are far more wary of others including humans when they are taking care of their young. Nil Einne (talk) 17:00, 11 September 2008 (UTC)[reply]
We (my friend and I) were discussing the differences in behaviour between pet parrots and pet cats/dogs, which don't really seem to mind when familiar humans interact with their young - even when they pick them up and play with them. On the other hand, something like a pet cockatoo or cockatiel (my friend has some) would go *absolutely fucking ballistic* if you tried the same thing with its chicks. --Kurt Shaped Box (talk) 17:31, 11 September 2008 (UTC)[reply]
I don't think that is entirely true. Many mother cats and dogs will be concerned if you try to handle their kittens/puppies particularly when they are very young. They may either react against you (snarl/hiss/try to bite/scratch) or may move them around to try and get away from you (or in extreme cases, may reject the young). Birds may perhaps be more protective then cats/dogs, but I definitely think all are quite protective of their young. (The obvious question is, how many mother cats/dogs and birds have you interacted with? In my case, none at all really but from what I've read I do think it's the case) It's worth bearing in mind that cats & dogs have both been domesticated for a while now whereas most birds haven't really been domesticated as far as I know so comparing the two isn't perhaps a fair comparison. From what I've seen in shows, you have to be very careful for example, with tigers when they've just given birth, even if you regularly handle the tiger normally. Also, I suspect it will have a fair bit to do with whether the animals in the wild are social animals. If it's normal for their young to interact with others at a fairly young age (as I presume it is for wolves) then they're less likely to have a problem with it. This is not the case for most birds (or tigers) so they're more likely to have a problem with it. P.S. What do chickens do? Nil Einne (talk) 18:09, 11 September 2008 (UTC)[reply]
In my experience, chickens just try to run off and lead the rest of their chicks away from you. They work on more of a numbers approach, rather than defend every single chick. Ducks on the other hand can be a little more aggressive. Franamax (talk) 08:48, 12 September 2008 (UTC)[reply]
Having spoken to my grandmother (who was raised on a farm), it's apparently the cockerel that tends to be the aggressive one when there are chicks wandering around. The hens (as Franamax says) just scuttle away with their chicks following behind. When it comes to collecting eggs, the hens will obviously bite if an attempt is made to remove eggs from beneath them, but they don't seem to even notice it happening if they're not actually on the nest. Again, the cockerel does, though - and gets very angry. --Kurt Shaped Box (talk) 22:59, 14 September 2008 (UTC)[reply]

Cat Induced Allergies

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About 2 and a half months ago we got a 5 year old white Persian cat. It has no ticks and flea infestation and we bathe it regularly about every week or 2 weeks as needed. Basically it is a healthy cat.

Recently about a week ago my Dad started complaining about allergy to the cat. But I believe that he is overacting. He is complaining of flu and throat complications. And I am of the opinion that this could very easily be due to viral or bacterial infection. My younger brother has allergic problems but throughout the 2 months stay of the cat he had no allergic reactions but about a week ago when his college opened he started having nose irritation etc. And that of course is because he now regularly breathes polluted (smoke, dust etc) air when traveling in the bus, at least that is what I believe.

On the basis of the above my Dad is insisting that we part with the cat. I am of course opposed to the idea. I have read somewhere that living with a pet cat can actually make your immune system resistant to cat allergies. Therefore I am of the view that the cat should stay.

I am not asking for medical advise but rather I would like to know if any of you have undergone a similar experience and the decisions that you made. Because a majority of people have pets or had them at some point in life. —Preceding unsigned comment added by 203.81.205.162 (talk) 00:50, 11 September 2008 (UTC)[reply]

You're trying to make a decision without data. An allergist would be able to perform a test that would tell whether your father is actually allergic to the cat, or not. It's unreasonable of him to insist you get rid of a pet if he doesn't take the test, just as it would be unreasonable of you to insist on keeping the pet if the test determines he's actually allergic. - Nunh-huh 04:25, 11 September 2008 (UTC)[reply]
An allergist could also explain more exactly the factor that triggers reaction in sensitive people. Mostly it's taken to the be fur, but there's a range of comment/information on Google about the effect of cat spit on the fur from grooming[2] among other things. Julia Rossi (talk) 07:57, 11 September 2008 (UTC)[reply]
Actually as far as I'm aware it's predominantly due to a? protein in the saliva which get onto the fur from the cat licking (and perhaps other means). This seems to be supported by Cat allergy. Nil Einne (talk) 16:57, 11 September 2008 (UTC)[reply]
Yeah, have them see an allergist to figure out for sure what is ailing them. But you should probably work out the terms ahead of time—if it turns out they aren't allergic to cats, keep the cat, but if they are, consider finding it another home. Don't give it to a shelter unless you are fine with the fact that it will probably be put to sleep. --98.217.8.46 (talk) 01:24, 12 September 2008 (UTC)[reply]
I used to believe that cat shelters meant that until I found out otherwise, and further OR is that while I had cats with short hair, it didn't affect the household, but a persian did with its excessive moltability. The cat had such a nice personality I got it a job in a pet store as the cusstomer service kitty, along with the tame parakeet etc. All true and a great itch relief for the rest, Julia Rossi (talk) 08:32, 12 September 2008 (UTC)[reply]
That's true, I found a Siamese to be the only breed of cat I could tolerate in a house. I like cats (and they like me) but a cat allergy is truly miserable. There is another way for all concerned to get along - get rid of the carpets, vacuum the floors and furniture every day, brush the cat every day and wash it regularly (nyuk - just try washing a cat), dust the shelves and tables every three days, and make sure Dad has an area where the cat is never allowed to go (den and bedroom, for instance). If you really want to, it can be done. Franamax (talk) 11:36, 12 September 2008 (UTC)[reply]

What is a Computer Scientist?

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My 10yr. son has to do research so a Computer Scientist. I really need some basic information so I can help him. What's involved in this person job? what type of equipment does this person need? Does this person need a uniform to do his/her job?

Thank You......Ms. Demetrius —Preceding unsigned comment added by 71.251.53.33 (talk) 00:56, 11 September 2008 (UTC)[reply]

Start with our article about computer science. It's a pretty diverse field, ranging from engineering to electronics to programming. One might sit at a desk, work in a clean room, etc. Depending on what one does, one might wear a suit, jeans, a uniform, some sort of safety gear or protective covering over "whatever" you want... DMacks (talk) 01:02, 11 September 2008 (UTC)[reply]
Some say that Edsger W. Dijkstra said "Computer Science is no more about computers than astronomy is about telescopes," giving a clue that computer scientists have been around longer than computers have. Computer scientists were around in the 1800s, as Ada Lovelace was the first computer programmer. --Kjoonlee 01:34, 11 September 2008 (UTC)[reply]
Also the first victim of vaporware. Clarityfiend (talk) 06:29, 11 September 2008 (UTC)[reply]
The article Computer scientist tries to explain it. Googling the term "What is a computer scientist?" (keeping the " ) will give you some other attempts at explaining it which are perhaps written better. EverGreg (talk) 09:36, 11 September 2008 (UTC)[reply]
He might try focusing on a small number of real computer scientists as an example. Donald Knuth comes to mind. Or Dijkstra. Or possibly compare a naive solution to a problem to a more advanced solution developed by computer scientists. (The obvious Bubble sort verses the unintuitive Quicksort for example) APL (talk) 18:17, 11 September 2008 (UTC)[reply]
Knuth may be a little above a 10 year old. Maybe try something your son would be more interested in, like game programmers. Paragon12321 03:22, 12 September 2008 (UTC)[reply]

Petrol pumps

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In an article in the London Times today, Matthew Parris complains of an incident when he drove up to a petrol pump on the wrong side. As he pulled the hose over the car's roof and attempted to fill up the tank that way, a loudspeaker voice bellowed at him that this was not allowed, and to drive to the other side or she would not switch on the pump.

As flammable liquids are involved I'm tempted to give the cashier the benefit of the doubt. Is there, in fact, any danger in pulling the hose of a petrol pump over the roof of your car and filling up from the wrong side? 81.171.134.226 (talk) 12:01, 11 September 2008 (UTC)[reply]

When I lived in California, there were stations that had signs advertising that their hoses were long enough that you could fill from either side. -- Coneslayer (talk) 12:37, 11 September 2008 (UTC)[reply]
I suppose one might scratch the paintwork, but I can't see any other likely hazards. DuncanHill (talk) 13:32, 11 September 2008 (UTC)[reply]

Sounds like a classic jobsworth. At the worst it'd be a little bit extra wear and tear on the car. People do this all the time (at least in my experience) without concern, and i'm pretty certain if there were any meaningful additional danger that the petrol-station would have clear signs about it (after all the relative danger of being on your mobile phone in a petrol station is small but they still - for now - forbid it.) 194.221.133.226 (talk) 14:08, 11 September 2008 (UTC)[reply]

thank you for expanding my knowledge of British English by using jobsworth! --LarryMac | Talk 14:49, 11 September 2008 (UTC)[reply]
Ooh me too! --jpgordon∇∆∇∆ 15:54, 11 September 2008 (UTC) [reply]
There's no danger to the pump - it is designed to pump wherever the hose is pulled to. There is possible danger to the customer being on the side of the car that traffic drives past as opposed to being between the pump and the car. In all reality, it is most likely a dumb rule that was made after someone sued the station (or company) for scratches on his or her car. -- kainaw 14:19, 11 September 2008 (UTC)[reply]
I'm told the smart thing to do is look at the little fuel pump symbol on the dashboard before you get out of the car - many indicate which side the filler cap is. Bazza (talk) 14:41, 11 September 2008 (UTC)[reply]
Snopes disagrees. Fribbler (talk) 14:54, 11 September 2008 (UTC)[reply]
That's not what Bazza means. Many pump symbols include an explicit arrow pointing left or right (my MINI does, and so do most rental cars I rent). Here's an example on a Toyota (quickest one I could find). -- Coneslayer (talk) 15:07, 11 September 2008 (UTC)[reply]
It actually mentions that in the Snopes article. Whoops! :-) Fribbler (talk) 15:19, 11 September 2008 (UTC)[reply]
So that's what the little triangle on the dashboard of my Toyota is for! 81.174.226.229 (talk) 15:42, 11 September 2008 (UTC)[reply]
I didn't mean an arrow, I did mean the side the pipe is positioned, as described in the Snopes article. The car I drive (VW) does what I said and, from 81's comment above, so do others. Different makes may not. Both Snopes and I, therefore, can be considered correct, especially if I pedanticly change "many" to "some" in my note above. Bazza (talk) 15:46, 11 September 2008 (UTC)[reply]
But since it's basically a fifty-fifty chance of being right, that's not really significant. That you are correct for your car is nothing more than confirmation bias. — Lomn 16:20, 11 September 2008 (UTC)[reply]
(ec) On many cars one can tell which side the filler cap is on by looking at the car before getting into it. DuncanHill (talk) 15:49, 11 September 2008 (UTC)[reply]
Just go back in time maybe 25 years or so, when many cars had the fill-pipe centered in on the rear. The license plate, which was on the fixed frame not on the trunk-lid, was the cover. DMacks (talk) 15:56, 11 September 2008 (UTC)[reply]
Not in Britain they didn't! I had a "solve it yourself" mystery book when I was a boy. The vital clue in one of the stories was to do with Fords having the filler cap under the number plate - now we had a Cortina, and I knew damn well that the filler cap was on the side. Being unable to solve the mystery because the publishers had failed to adapt the book properly to the British market was a great disappointment to me. DuncanHill (talk) 16:00, 11 September 2008 (UTC)[reply]
That was Wikipedia Brown and the Global Perspective, right? I think I read that one. -- Coneslayer (talk) 16:20, 11 September 2008 (UTC)[reply]
I don't think there will be any danger but it sounds to me there might be some reasons why they won't want you doing it. Firstly if the hose isn't far enough to reach the tank, the person may try to stretch it to reach. This is unlikely to be dangerous but may increase wear and tear on the hose. Secondly if the person is extremely lazy, they may not bother to put the hose back properly and may just leave it lying across the road. Again I doubt there will be any danger but it may be ran over (again increasing wear and tear) and/or requires the attendant to go and put it back. Thirdly if someone knocks the hose it may be damaged and of course is likely to damage the car that hits it (again probably not dangerous but may liable to make problems for the petrol station). Nil Einne (talk) 16:49, 11 September 2008 (UTC)[reply]
Take a look at that picture of the gas pump up above. The hose is partly filled with gasoline from the last person who filled their car up. If you're trying to stretch the hose over to the other side of your car and you lift it the wrong way, isn't there a fairly good chance you'll spill gas all over your car (and yourself)? Franamax (talk) 08:41, 12 September 2008 (UTC)[reply]
Nahh, the shutoff valve in the handle is supposed to prevent that. There's possibly a small amount in the last 8 inches of nozzle, but only if the last person pulled it out REALLY quickly after refueling. --DaHorsesMouth (talk) 22:39, 12 September 2008 (UTC)[reply]
Perhaps the reason that it is unallowed is that if the customer is standing on the far side of the car, they won't be able to reach the shutoff lever on the pump in an emergency. I've stretched the hose over my car once (and mine's just a narrow Corolla hatchback) and I noticed that the extra twisting and manipulations I had to do to get the nozzle into the right position resulted in some spilled petrol when I removed it. I find it curious that the Snopes article thought that putting the fuel cap on the same side of all cars would be a good idea, given that it would make it mean you couldn't have a car on each side of one pump. Maelin (Talk | Contribs) 09:41, 15 September 2008 (UTC)[reply]

polymers

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Under what condition does ethzlene gets converted into polyethylene?220.225.211.171 (talk) 12:33, 11 September 2008 (UTC)[reply]

Depends on if you mean LDPE or HDPE.--Stone (talk) 12:39, 11 September 2008 (UTC)[reply]

Is the LHC the coldest place in the universe?

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The temperature of intergalactic space is 2.73 K. The operating temperature of the LHC is 1.9 K, and its volume is around 80000 cubic metres. Is there any known region of the universe of this size that is colder than the collider? --Taejo|대조 13:20, 11 September 2008 (UTC)[reply]

According to our article, the Boomerang Nebula is at about 1K. It's the only thing known to astronomers that's colder than the microwave background. Algebraist 13:23, 11 September 2008 (UTC)[reply]
Do astronomers not know about the LHC? :) --Taejo|대조 13:34, 11 September 2008 (UTC)[reply]
Algebraist intelligently included "known to astronomers" because it is impossible to know the "coldest" or "hottest" or "largest" or "smallest" anything when referring to space. Most of it is unknown, so we can only answer with "coldest place in known space". And yes, astronomers know about the LHC. It is important to know about something that is guaranteed to suck up Earth in a black hole by this time next year. -- kainaw 14:16, 11 September 2008 (UTC)[reply]
Well, that's why I thought astronomers would know about the LHC. --Taejo|대조 16:01, 11 September 2008 (UTC)[reply]
Well, there are labs where they've got down to billionths of a degree above absolute zero, if memory serves. The Boomerang Nebula is the coldest known place that wasn't cooled down by man. --Tango (talk) 14:23, 11 September 2008 (UTC)[reply]

Population of the Philippines

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COULD YAH PLS. GIVE ME THE POPULATION OF THE PHILIPPINES, CAINTA & RIZAL.....TNX?Jjhg (talk) 13:53, 11 September 2008 (UTC)[reply]

Our article Philippines should contain the information you are looking for. By the way, this sort of question is probably better suited to the Humanities desk. Oh, and try not to use ALL CAPITALS when asking questions - it can look like you are shouting and may annoy some users. DuncanHill (talk) 13:58, 11 September 2008 (UTC)[reply]

Welding under water

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What are the processes taken to weld under water? Discuss the differences between welding on surface and under water? What is the trick behind under water welding? What are the equipments used? Are the equipments the same as surface welding? What are the side effects on welder? Which is stronger surface or under water welding? What is the meaning on the abbreviation written on surface electrode? Does the carbon light has effect on eyes as in under water welding? What are the conditions for a surface welder to become an under water welder? Lastly Every other things describe under water welding

Thanks —Preceding unsigned comment added by Advancepunche (talkcontribs) 14:21, 11 September 2008 (UTC)[reply]

Try reading underwater welding and ask if any of your questions are not answered. -- kainaw 14:25, 11 September 2008 (UTC)[reply]

Entropy and the Direction of Time

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In the dimension article, it states that "we perceive time as flowing in the direction of increasing entropy." Why is that true? Sappysap (talk) 14:55, 11 September 2008 (UTC)[reply]

As noted prior to that parenthetical expression, it's because physics models generally treat time in that fashion. In a closed system, entropy increases (per the second law of thermodynamics). This is a convenient shorthand for time with regard to otherwise time-symmetric equations. The statement should not be interpreted in isolation, however -- it is not an attempt to say that you and I examine the entropy around us to determine that time exists in the everyday. — Lomn 15:21, 11 September 2008 (UTC)[reply]
It's interesting to note that the 2nd law of thermodynamics, or at least the logic behind it, is time symmetric. Entropy ought to increase in both directions in time from any given point (which isn't actually possible, of course, so I guess it would all just cancel out and stay roughly constant), it's just because the big bang had extremely low entropy, so entropy in the past is fixed at a low point, that it can only increase towards the future. --Tango (talk) 17:20, 11 September 2008 (UTC)[reply]
Try this thought experiment. Suppose you and the whole universe suddenly start to move "backwards in time", all physical processes are exactly reversed, and your memories are erased as you go back. So when you get "back" to one hour ago you have exactly the same memories as you had the first time you went through the time-point "one hour ago", the only difference is that you (and the universe) are now moving in the opposite direction along the "time dimension". How would you know that time had reversed ? How could you tell ? Does this concept of "moving backwards in time" even make sense ? In The End of Time: The Next Revolution in Our Understanding of the Universe Julian Barbour argues in this way that time is an illusion, and that the only reason we peceive time as flowing in the direction of increasing entropy is that this is the only way in which memory can work, given the second law of thermodynamics. It is impossible to remember the future, not because "it hasn't happened yet", but because it is a state of higher entropy than the memory itself. Gandalf61 (talk) 15:25, 11 September 2008 (UTC)[reply]
We have some articles on arrow of time and entropy (arrow of time), although they can be kind of confusing. --Bennybp (talk) 16:36, 11 September 2008 (UTC)[reply]
Shouldn't the psychological arrow of time be pointed in the opposite direction? Being as objective as I possibly can, I'd like to state that my thoughts are far more ordered now than they were when I was 13. Sappysap (talk) 23:36, 11 September 2008 (UTC)[reply]
I don't think you can apply your thoughts in terms of entropy. Anyway your brain isn't a closed system. --Mark PEA (talk) 12:08, 12 September 2008 (UTC)[reply]
Indeed - it's not a closed system, and that's the key detail. In order to store a memory you need to use energy and that's going to increase entropy somewhere (heating the air around you, turning food into carbon dioxide and water, etc). --Tango (talk) 21:27, 12 September 2008 (UTC)[reply]

Are all alleles genes?

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Are alleles genes or do they just determine how the gene turns out? Thanks Kim —Preceding unsigned comment added by 71.176.185.204 (talk) 15:08, 11 September 2008 (UTC)[reply]

All Alleles are genes. And all Genes are made of DNA. "How the gene turns out" is referred to as the phenotype. The genes themselves are physical DNA sequences and don't "turn out" to be anything else. Fribbler (talk) 15:16, 11 September 2008 (UTC)[reply]

Disadvantages of needleguns

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I added a second question below on September 14. It's been two days, and no one's taken a stab at it, so I've boldfaced it. I will de-boldface it once someone answers.Lowellian (reply) 07:12, 16 September 2008 (UTC)[reply]

In Wikipedia's article on needleguns, there is a section heading entitled "Advantages" which gives a whole bunch of advantages of needleguns. There is no section heading called "Disadvantages", and no discussion of disadvantages in the article. Yet, clearly, there must be significant disadvantages, because if there weren't, then everybody who uses guns would be using needleguns — while in reality, the opposite is true: needleguns are extremely rare in comparison to other types of firearms. So, what are the disadvantages of needleguns, and could someone please add them to the article? —Lowellian (reply) 16:21, 11 September 2008 (UTC)[reply]

I've heard of flechettes, but didn't know people used the term "needlegun" to refer to such things. I'd assumed "needleguns" were sci-fi only. High-velocity, high sectional density projectiles would tend to overpenetrate, which is a disadvantage. But, this is just me speculating, and I'm not a reliable source, so I don't think I'd want to stick this into the article. Friday (talk) 16:35, 11 September 2008 (UTC)[reply]
Well, I would guess the major disadvantage is that they are mostly hypothetical. I'm not aware of an existing system. Talking about handguns, hypothetically of course, the major disadvantage would be the low stopping power. Needles penetrate well, but do little damage. The overall energy of the projectiles would also be rather low, implying low range. Also, it's unclear of how to power such a gun. Chemical with a sabot would eliminate most advantages (rate of fire, ammunition size) while adding complexity and inaccuracy (the sabot needs to be accelerated and drops away in flight). For more Sci-Fi approaches, you would need a portable power plant, which might not be reasonable. --Stephan Schulz (talk) 16:42, 11 September 2008 (UTC)[reply]
Why are they hypothetical? Why couldn't you just replace a bullet with a flechette in a normal firearm and get a flechette rifle?Lowellian (reply) 16:04, 14 September 2008 (UTC)[reply]
A "needle" gun actually doesn't make a very effective weapon, as the small mass of a needle slows down much more rapidly in flight than a bullet and hence has limited range and accuracy. Most flechettes actually look more like nails than needles, and that's largely to provide them enough mass to be practical. Dragons flight (talk) 21:03, 11 September 2008 (UTC)[reply]

Was there German Genetic Engineering using X-rays in 1945?

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After World War II, in the years 1945 to 1947 the U.S. took besides many factories all intellectual property that they could from Germany, all patents, the industrial processes etc. (good book on the topic) A U.S. agricultural officer (colonel) in occupied Germany wrote a book about his experiences in occupied Germany, it is available online. This is a quote about one of the things they took in 1945.

"Members of our agricultural staff were in time to discover some rather interesting and intriguing developments in plant science, especially about the production of higher-yielding plants by breaking up certain chromosomes through radiation. Some of this got to the United States and is widely applied in areas of grain production and horticultural research today."[3]
  • Is he speaking about a form of Genetic Engineering by inducing mutation using x-rays, or is it be something more advanced?
  • What is this method/technology that the Americans copied from the Germans called?

--Stor stark7 Speak 17:01, 11 September 2008 (UTC)[reply]

The use of a large variety of mutagens [4] to help generate varieties is extremely common place in modern day plant breeding (check the article) and has been since around the end of WW2. Take a look at this image for example [5]. No, it's not usually considered genetic engineering. However it is rather different from what many people seem to have in their minds (particularly those nuts about organic farming who hate anything involving GE) about someone breeding different varieties they find until they get a plant they want. Nil Einne (talk) 17:50, 11 September 2008 (UTC)[reply]
The systematic use of radiation to induce mutation was done far earlier than World War II. Thomas Hunt Morgan was experimenting with radiation as a way of producing different varieties of fruit fly as early as the 1910s. I don't know precisely who started using it for specifically agricultural purposes but the fact that mutations in large populations could be increased with radiation doses had been figured out pretty early on, and I would not be surprised if it was one of the many approaches taken at agricultural stations in the US pre-WWII, but that's just my own speculation. It's not necessarily the best way to get new varieties, though. --98.217.8.46 (talk) 23:28, 11 September 2008 (UTC)[reply]

Over my head

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I have a teacher who has a habit of looking over everyone's head while he's teaching class. He looks somewhere above the windows in the back of the room. I used to know a guy that did this whenever he was talking to someone. He'd never look you in the eye while talking. Is there a term for this? Dismas|(talk) 17:44, 11 September 2008 (UTC)[reply]

I don't think there's a term for it, since it could be any of several unrelated reasons someone may appear to do this. Two social issues come to mind are nervousness (feeling awkward making eye contact) and some sort of aloofness/snootiness (looking down at someone while talking). OTOH, could be a vision problem: a co-worker years ago always looked like he was looking a few feet to the left of where he actually was looking, which if you didn't know it, you'd always think he was ignoring you and listening/talking to the person two chairs over. DMacks (talk) 17:58, 11 September 2008 (UTC)[reply]
I typically don't make eye contact when I talk (and teach as a TA). It's something I'm working on, but never felt like doing. For me, I believe it's because I'm a strong auditory learner - I'm not actually "looking" at or even "focusing" on anything, I'm just devoting more of my brain to hearing than seeing and more or less "shutting down" my eyes for a bit. I don't really need to look at faces/body language - I get almost all of my cues from the tone, inflection, etc of voices. I know it's distracting to some people, but it's who I am. If you force me to look at you, I'll probably forget what you said. Actually, that might even be some very mild autism, but I've never been tested. (I know that didn't actually answer your question for a term, just something I'd like people to know :) --Bennybp (talk) 19:12, 11 September 2008 (UTC)[reply]
Thanks, now I'll know in case I'm in one of your classes.  ;) Dismas|(talk) 20:45, 11 September 2008 (UTC)[reply]
Actually, I think the term(s) you are looking for are eye aversion or gaze aversion. See Eye_contact#Eye_aversion_and_mental_processing and a kind of interesting paper (although maybe unpublished) here. Warning: PDF --Bennybp (talk) 19:19, 11 September 2008 (UTC)[reply]
I always avoid eye contact. Not out of rudeness, but due to poor vision, as mentioned by user:DMacks. Because of my vision I find facial expressions hard to interpret, so avoiding eye contact allows people to know that I don't register their expressions. Fribbler (talk) 22:49, 11 September 2008 (UTC)[reply]
Asperger syndrome may be of interest. —Preceding unsigned comment added by 98.169.163.20 (talk) 00:12, 12 September 2008 (UTC)[reply]

Facts that oppose evidence for evolution

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No, this is not a question about intelligent design. I just want to know if some facts seems paradoxal confronted with the idea of evolution. Something that cannot be easily explained considering evolution. Mr.K. (talk) 18:37, 11 September 2008 (UTC)[reply]

The primary argument against evolution is the complexity of life. Here are a few ways of putting it:
  • How could the human eye just 'evolve'?
  • Flight would be incredibly useful. Why can't humans fly?
  • Shouldn't there only be one super-evolved creature instead of all different kinds?
Those seem paradoxical, but are actually based on ignorance. -- kainaw 18:42, 11 September 2008 (UTC)[reply]
Emotions and the concept of good and evil are also popular ones to point to. -- MacAddct  1984 (talk &#149; contribs) 19:30, 11 September 2008 (UTC)[reply]
How come there are so few transitional fossils? Also note that in many cases when pro-evolutionists say "we know the answer to that" it often means that they have come up with a suggestion which they think is plausible - not that they have found evidence that it happened that way. DJ Clayworth (talk) 20:38, 11 September 2008 (UTC)[reply]
Actually, there are quite a lot of transitional fossils. I remember scaring off a Jehovah's Witness when I was a university student by offering to show him some of my palæontology textbooks, after he had made a similar "point". DuncanHill (talk) 20:44, 11 September 2008 (UTC)[reply]
Claiming lack of evidence for evolution is evidence against it is just as wrong as claiming that lack of evidence against it is evidence for it. It doesn't matter if anyone has clear proof of transitional fossils or if anyone can show clear proof of anything. Evidence against evolution must be real evidence, not a claim about lack of evidence. -- kainaw 23:46, 11 September 2008 (UTC)[reply]
That's not entirely true - if you can show that a theory would produce a certain type of evidence with a high probability and you can't find that evidence, that would suggest the theory is false. For example, I theorise that no humans can fly since if any could fly I would almost certainly have heard about it. --Tango (talk) 23:52, 11 September 2008 (UTC)[reply]
A failed test of a hypothesis is evidence against the hypothesis. That is evidence. Claiming that a hypothesis has not been tested is evidence against the hypothesis is not evidence against the hypothesis. On this specific topic, there are claims such as "Evolutionists cannot show me a half-monkey/half-human, so that means there is no such thing as evolution." There is no hypothesis in evolution that there exists half-monkey/half-humans. So, the lack of proof that there are half-monkey/half-humans is not evidence against evolution. Similarly, evolution doesn't claim that each and every fossil will survive through all time and be found. So, lack of evidence of fossils is not evidence against evolution. I have a problem with both sides of this argument. Evolutionist for evolutionst sake do not have a clue what they are talking about. Anti-evolutionists (all lumped together) for anti-evolutionist sake do not have a clue what they are talking about. -- kainaw 00:00, 12 September 2008 (UTC)[reply]
Ah, now you're describing the straw man fallacy. However, I disagree with the statement "There is no hypothesis in evolution that there exists half-monkey/half-humans.", given a sufficiently incorrect definition of "monkey" (you have to interpret words in the way the people saying them mean, rather than what they actually mean) there should be some creature inbetween "monkeys" (proto-hominids, I think would be a more accurate term) and humans. Scientists looking for such a link and not finding on is evidence against evolution (it's not very strong evidence, though, given the fact that most creatures don't end up fossilised so you have to get pretty lucky to find one and there are plenty of places we still haven't looked). --Tango (talk) 17:55, 12 September 2008 (UTC)[reply]
One thing that's always bugged me, not necessarily about evolution per se but our understandings of it, is why humans are so vastly overpowered in terms of cognitive ability compared to other primates. I mean, a human being that was half as intelligence as our species potential maximum is still capable of surviving just fine even in a hostile environment. (I suspect the answer has to do with the fact that there were multiple smart-primate species competing with one another, because if it is just humans against other animals, I doubt we'd have gotten this smart, but humans against other smart things, well, then you've got an arms race.) I've never really seen this fleshed out well, in part because our understanding of the nuts and bolts of human evolution is pretty speculative (a fossil here, a grave there). --98.217.8.46 (talk) 23:20, 11 September 2008 (UTC)[reply]
Are you familiar with Neanderthals? Exactly how they ended up extinct and we ended up thriving is still an open question, as far as I know (although I remember reading recently about some evidence that they were just as intelligent as early Homo Sapiens). --Tango (talk) 23:24, 11 September 2008 (UTC)[reply]
Of course I'm familiar with Neanderthals, but it doesn't really solve it for me. The existence of one other somewhat intelligent primate species doesn't really explain why we're so overpowered. This isn't an anti-evolutionary complaint, just a "boy we really don't understand this" complaint. My deeper suspicion is that the human propensity for intra-species violence—far more than most other animals—is somewhat related to this. (Of course Darwin thought it was probably sexual selection, which is fairly similar.) But it'd be nice to have a better understanding, or at least a better model, of how you get to such a point. --98.217.8.46 (talk) 12:47, 12 September 2008 (UTC)[reply]
You're absolutely right, I didn't mean to suggest Neanderthals would give you the answer, just that they're an interesting topic closely related to that question. It's still an open question, as far as I know. --Tango (talk) 17:48, 12 September 2008 (UTC)[reply]
I read that, apparently, there's evidence to suggest that humans committed mass genocide against the Neanderthals. —Preceding unsigned comment added by 65.92.231.82 (talk) 00:25, 14 September 2008 (UTC)[reply]
Intelligence is not, prima facie, a superior evolutionary trait - and this is something that a lot of people who argue about evolution get hung up on. From an intelligent level, we can look and say, hey, great - with science we can increase fertility, defeat the elements, and hunt to extinction anything vaguely resembling a predator, sure. But that's the conclusion begging the premise. I think a useful read is called "The Sickness Gene" or something along those lines - the trifecta of surviving to breed, breeding "most", and having offspring that hit A+B is all there is. In that respect, humans are a vastly inferior form of life to bacteria and cockroaches (and, from a health perspective, a viral epidemic could effectively obliterate the human population... extremophiles would require an astronomical event to be substantively impacted). I believe Mike Judge's movie Idiocracy was another illustration of the principle of evolution - the most fit to breed is not the qualifier we tend to think it is. Sorry, but there's really no counter-evolutionary evidence - Darwin's finches and micro-evolution are difficult to argue with. The best that can be done is circumstantial arguments - OH, HA HA, it turns out that the velociraptor didn't, actually, evolve into turkeys, take that Science! All your precious THEORIES are now rebuffed! ... no, sorry, it doesn't work that way. No more then forgetting to carry a one, one time when you're doing times tables means you're a fundamental failure when it comes to multiplication. 98.169.163.20 (talk) 00:08, 12 September 2008 (UTC)[reply]
The best explanation that I'm aware of (admittedly, I have no evidence to support it, but it sounds plausible) is that human intelligence reached a sort of critical mass, where we developed sufficient cultural complexity that we bootstrapped the intelligence evolution process. In the ancestral environment, humans weren't just using their intellects to compete against other species, they were also competing against each other - for food, mating rights, social status, etc. The increase of intelligence may have accelerated as intelligence became more important in human societies. Don't forget, also, that our methods of developing and fostering intelligence in each other (i.e. education) have also had thousands of years of evolution. Maelin (Talk | Contribs) 09:54, 15 September 2008 (UTC)[reply]

There is a very useful and easily-searchable web site that makes an effort to respond to all criticisms of the Theory of Evolution. It is called "An Index to Creationist Claims". Saukkomies 09:26, 13 September 2008 (UTC)[reply]

The reason why humans cant fly is they can survive without it as it already is humans are dominant so they did not evolve to have wings becuase evolution isnt about making things easy is making it so you can survive another opinion in why only the humans where dominant and not other things is that humans are almost all the animals and alien animals in the world it is infact possible that we are aliens to this planet becuase there was evidence of life on mars and there are piecies of rock from mars that still have live alien cells and could have mixed into the water since if a meteor hit and when fish where evolving and land animals they where exposed to it so that then they would be very smart have emotions and other worldy things. dont believe what churches tell you science is not leading to religion or anything else to do with it...

Plastic bullet for handgun

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Why cops and the like don´t use plastic bullet in their handgun? —Preceding unsigned comment added by Mr.K. (talkcontribs) 18:39, 11 September 2008 (UTC)[reply]

By plastic, you probably mean ceramic since plastics that we experience in everyday use could not sustain the acceleration of being fired from a gun. As far as ceramics, there are some that could easily withstand being fired from a gun better than lead/metal, but they cost much more than lead/metal used in bullets. Since bullets are good enough as is, there is no need to spend more. -- kainaw 18:58, 11 September 2008 (UTC)[reply]
Or maybe the OP meant rubber bullets? -- MacAddct  1984 (talk &#149; contribs) 19:10, 11 September 2008 (UTC)[reply]
(edit conflict) I think Mr. K. actually means rubber. Rubber bullets and other types of nonlethal munitions are more range specific. Depending on the charge, rubber can be lethal or so harmless as to be ineffective. They sell them for different ranges but changing bullets on the spot is impractical for a last resort weapon. That's why they're mostly used for crowd control, when they can plan better on how to respond. There are arms manufacturers working on nonlethal guns where you can 'dial in' your range for rubber munitions (air power), but those aren't widespread yet. - Lambajan 19:14, 11 September 2008 (UTC)[reply]
I suspect the original questioner actually meant what he said, namely plastic bullets. DuncanHill (talk) 20:33, 11 September 2008 (UTC)[reply]
And just so Mr K understands, plastic bullets (or rubber bullets) are not simply a different kind of bullet fired from a normal gun - they are large projectiles fired from a special kind of gun: which explains why cops don't use them in their handguns. DJ Clayworth (talk) 20:35, 11 September 2008 (UTC)[reply]
Yow, plastic bullets are meant to be fired "below the waist" of the target. I don't like the sound of that... Franamax (talk) 08:29, 12 September 2008 (UTC)[reply]
I guess it boils down to whether you would you rather lose something below your waist or lose your life... Nil Einne (talk) 10:54, 12 September 2008 (UTC)[reply]
Some people might ask, is there a difference? Somehow "fill ya full of clay" doesn't have the same punch. Julia Rossi (talk) 11:56, 12 September 2008 (UTC)[reply]
I suspect only a small minority though, when they actually think about it Nil Einne (talk) 12:38, 13 September 2008 (UTC)[reply]

LHC as time after big bang

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Regarding the new LHC, how close to the big bang is an energy of 7 Tev per particule? Lerichard (talk) 21:01, 11 September 2008 (UTC)[reply]

It looks like somewhere in the Electroweak epoch, from 10-36 seconds to 10-12 seconds after the Big Bang. That's just based on my reading of the pages linked to from Timeline of the Big Bang, so could be wrong. --Tango (talk) 22:41, 11 September 2008 (UTC)[reply]
Agreed. It's sometime after the end of the inflationary epoch, which ended at about 10-32 seconds, but before the weak force separated from the electromagnetic force at about 10-12 seconds. For a ballpark figure, I think this was the typical energy per particle at about 10-13 or 10-14 seconds after the Big Bang. Gandalf61 (talk) 12:50, 12 September 2008 (UTC)[reply]
I was never happy with the inflationary epoch. "We don't see magnetic monopole, so maybe they are far away!" There was no attempt to apply the scientific method. Although now that I read Alan Guth's article it sounds as if WMAP confirmed some predictions of his theory? The article is vague and unsourced - can someone expand on that for me? Plasticup T/C 16:12, 12 September 2008 (UTC)[reply]

Fantastic Structure?

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Is this real? It's seems pretty authentic, but I can't find any other sources. PerfectProposal 21:49, 11 September 2008 (UTC)[reply]

It looks like a giant building proposal, but is probably beyond building technology if you read the comments lower down. Graeme Bartlett (talk) 22:15, 11 September 2008 (UTC)[reply]
It is very common for Architects/Civil Engineers to propose designs for currently unconstructable buildings. Like Frank Lloyd Wright's The Illinois. It is a "portfolio" piece, that is it won't be built but shows the designers abilities. Fribbler (talk) 22:57, 11 September 2008 (UTC)[reply]
I would think a key component of a designer's ability is their ability to design something within set limits - "possible to build" would be a limit I would set on any commission for design work. --Tango (talk) 23:21, 11 September 2008 (UTC)[reply]
What a crazy design. I thought Burj Dubai was pretty excessive but that thing is like three or four times taller. --98.217.8.46 (talk) 23:10, 11 September 2008 (UTC)[reply]
The same company was pitching this idea in Tokyo until there wasn't enough money there for it. Now, they are pitching it in Dubai - until that money dries up. My opinion - they increase their stock revenue by pitching these ideas and profit. Then, they invest elsewhere until they find a new area to pitch an idea to. They buy back their depleted stock, pitch the idea, drive up their stock value, and sell. -- kainaw 00:04, 12 September 2008 (UTC)[reply]
This is approaching the idea for a mini-arcology. It's not really practically feasible with the technology and costs of that technology that we have today. Also, attempting to insure this building would be a nightmare. —Lowellian (reply) 05:11, 12 September 2008 (UTC)[reply]
When an engineer scrutinizes the plans and tells me it's not possible then I'll believe it's not possible. If Kainaw's right and they're going around pitching this thing and the only problem is not enough money then it probably is possible. I'm sure that if Japan turned it down because their engineers gave it a 'thumbs down' then they wouldn't be able to pitch it anywhere else. - Lambajan 13:40, 12 September 2008 (UTC)[reply]
But would we necessarily know if the Japanese engineers gave it a thumbs down? Zain Ebrahim (talk) 13:48, 12 September 2008 (UTC)[reply]
It was never given a thumbs up in Japan. The only reason anyone really heard about it was because it was featured on a Discovery program about really big buildings and some other channel that had a show about really big things. The shows made every attempt to give the appearance that this building was going to built soon in Japan, but the truth is that there are no current plans to build. It is just a small group of guys pitching the idea here and there. I figure that when this idea runs out, they'll start pitching either cities in orbit or under-ocean cities. -- kainaw 14:05, 12 September 2008 (UTC)[reply]