Wikipedia:Reference desk/Archives/Science/2007 April 8

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April 8

Understanding the Feline Way of Picking Food

I have three cats. Every day, I keep for them two bowls of dry food. I noticed that the food level in the two bowls, during the day, is decreasing at a similar rate. When I spy on them, it seems that they are purposedly picking food from the one bowl which has more food at that time. Why could that be? Why not finishing one bowl then attacking the other?--JLdesAlpins 00:39, 8 April 2007 (UTC)

In nature they need to protect their food or it could be stolen. Given the choice of two food morsels to protect, it would make sense to protect the biggest one, so perhaps that instinct is still with domestic cats. StuRat 01:38, 8 April 2007 (UTC)

I don't know about your cats, but mine will start to complain if I feed him the same brand of food more than once or twice in a row. Maybe yours just like some variety, too. —Ilmari Karonen (talk) 02:20, 8 April 2007 (UTC)

Alternatively, if the bowls both contain the same food, maybe they find it easier to eat from the larger pile. After all, they have no hands, and the feline mouth, while capable of it, isn't really adapted to fishing bits of dry kibble from the bottom of a bowl. Or maybe they just instinctively pick the pile that looks more appetizing, which might well be, in the absence of any other differences, the larger one. I doubt cats have the capability for the kind of abstract rationalization that would allow them to convince themselves that the piles really are homogenous and of identical consistency, even if one of them looks intuitively like a better meal than the other. And even if they did, why would they care — it's not like any other eating strategy is actually any better than the one they're actually using. —Ilmari Karonen (talk) 02:30, 8 April 2007 (UTC)

In most public restrooms, there are two rolls of toilet paper, so that if one runs out before an attendant can replace it, a hapless stall user will not be left high and dry (or something).

In many such restrooms, the second roll is concealed in a dispensing device and does not drop down until the first roll is consumed. In some restrooms, however, both rolls are equally accessible (i.e. on two simple dispensers, without any fancy, expensive cascade mechanisms).

When both rolls are equally accessible, you will notice that they are used up at a nearly equivalent rate, such that they run out at almost exactly the same time, thus negating most of the utility of the scheme.

I submit that the reason for this phenomenon is the same as for the two bowls of cat food. —Steve Summit (talk) 02:36, 8 April 2007 (UTC)

Another less likely possibility is that they can't find the food in a bowl that's almost empty. I don't believe cats have color vision, which makes it hard for them to find certain items that are the same shade as the background. I've been amazed at my cat's inability to find certain foods on the floor. It sniffs around the area, but can't seem to locate food that I can see as plainly as daylight. StuRat 04:12, 8 April 2007 (UTC)

Instead of believing, you could look it up. For example, here: www.straightdope.com/classics/a2_004.html Or even here. Cats do have color vision; it just isn't as good as ours. (So, yeah, they may have trouble picking out small objects by sight sometimes.) --Anon, April 4, 2007, 05:44 (UTC).

As I have read from a book of a Sahara explorer, some snail-eating foxes have the habit of picking only a few snails from a bush (so they can reproduce until the next meal) and traveling miles to visit other bushes. If they had eaten all the snails from a given bush, the snail population would have died out (and a little later, the foxes too because of starvation). Maybe there is some reason in the case of the cats too. In their natural habitat they eat live food, so they must spare some of it. --V. Szabolcs 12:06, 8 April 2007 (UTC)

Information entropy of the universe

What is the total quantity of information entropy in the universe? Is it increasing or decreasing? NeonMerlin 02:05, 8 April 2007 (UTC)

see Entropy#Entropy and cosmology. Jon513 13:55, 8 April 2007 (UTC)

Total Entropy is constantly increasing. Entropy is a measure of disorder - chaos - whatever. The tendancy for entropy to increase is very evident in daily life - things break - things that once worked stop working - tidy things get untidy. It's very rare for disorderly things to spontaneously get organised. It takes work - energy - to make something more organised than it was. Extracting energy disorganises things - so creating a little pocket of better organisation causes more disorder elsewhere...so whilst you can locally reverse the flow of entropy - on a global scale, it increases continually. SteveBaker 17:47, 8 April 2007 (UTC)

microbiology

why are eukaryote diseases more difficult to treat than prokaryote diseases? —The preceding unsigned comment was added by 4.152.24.220 (talk) 03:05, 8 April 2007 (UTC).

Many diseases, including infectious ones that you are asking about, rely on drugs exploiting the differences between human cells and cells of infectious organisms. For example, one of the first antibiotics, penicillin, worked well and was well tolerated because it inhibits the synthesis of bacterial cell walls, which human cells lack. In general, because humans are eukaryotic, there are fewer differences between humans and other eukaryotic organisms than there are between humans and prokaryotic organisms. The more differences between host and infectious organism, the easier to treat. I'm sure there are other good reasons, but this is a major one. --David Iberri (talk) 04:28, 8 April 2007 (UTC)

Evangelical christians with dilated eyes

I was just watching the movie Jesus Camp, and noticed something a bit strange. Many of the children (and some of the adults) have extremely dilated pupils, like they were on MDMA or something like that. One of my friends recently became a born again christian, and I noticed the same thing happening to him... huge dilated pupils. When people feel this way, I'm thinking it must be the body releasing endorphins that make them feel that way, which allows them to feel like jesus is inside of them, and that leads to the dilated pupils. Has anyone else noticed this, or have any thoughts on it? 67.142.130.20 03:12, 8 April 2007 (UTC) Anonymous

Its caused by the Jesus juice. Seriously, pupil dilation is a autonomic response and therefore if one could imagine that is there is such a thing as the Holy Spirit then it is not a huge leap of "faith" to imagine it could influence the release of neurotransmitters during spiritual possession. Of course, it could simply be a type of mass hysteria and resulting physiological effect. Alternatively they could be whacked out of their mind on alcohol or be brain dead. Rockpocket 05:47, 8 April 2007 (UTC)

Yellow moon?

As I was walking back home last night/this morning (~6:30 UTC), I noticed that the moon was yellow-orange. The lunar eclipse happened weeks ago, so what else could account for this?

Thanks. 137.99.165.83 06:08, 8 April 2007 (UTC)

When the moon is at a lower angle in the sky, its light has to pass through more atmosphere, which scatters the higher wavelength light (like the sun at sunset). Pollution makes this worse (more crap in the air to scatter light), and can be so bad that the moon appears oddly coloured even when at a pretty high angle. -- Consumed Crustacean (talk) 06:28, 8 April 2007 (UTC)

Human carry electric

A man carry electric which could be felt when we touch him like we feel mild electric shock. What is cause ? —The preceding unsigned comment was added by 89.148.17.212 (talk) 06:33, 8 April 2007 (UTC).

One way to generate that charge is by rubbing socks on some carpets, due to the triboelectric effect. Another way for a charge to build up is if a person maintains insulated above ground, such as riding in a car for a length of time. Then the person will get out and it'll discharge when he or she touches something like the car frame. I also get it wearing my dockers shoes and walk around in one specific store, and I have never figured out why. --Wirbelwindヴィルヴェルヴィント (talk) 07:11, 8 April 2007 (UTC)

The soles of your shoes and the carpet material in the store are widely spaced on the triboelectric series? —The preceding unsigned comment was added by 88.110.155.118 (talk) 18:50, 8 April 2007 (UTC).

Magic mushrooms - effect on non-humans

Does anyone know if magic mushrooms have a psychedelic effect on living creatures other than humans? On a more general note - do animals and birds ever actively seek out and consume naturally occurring psychedelic substances? --Kurt Shaped Box 07:34, 8 April 2007 (UTC)

According to Animals and Psychedelics: The Natural World and the Instinct to Alter Consciousness, Giorgio Samorini, Park Street Press, (ISBN 0892819863), literally hundreds of animals seek out hallucinogenic substances (and plenty more get wasted by accident, ruffied by Mother Nature, or by nasty men in white coats). A few examples: a type of ant will suck a hallucinogen from the abdomen of a lomechusa beetle. Male mandrills will get high on the root of a iboga root then hang around until the are tripping nicely before before fighting it out without another male over territory. Of course, in addition to experimenting on themselves those crazy scientists in the 60s tried out lots of drugs on animals. It appears elephants and LSD don't mix too well [1], but cats get a groove on (note: if you are of a sensitive nature, don't click here) and dogs that ingest magic mushrooms "frequently snap at invisible flies, may be extremely depressed, stagger when walking and become comatose." [2] Not unlike a trip I once had. Rockpocket 09:09, 8 April 2007 (UTC)

A friend of mine had a cat who ate some of his mushrooms. This was a few years ago, but the cat was acting strangely, with a wobbly walk. − Twas Now ( talk • contribs • e-mail ) 15:17, 8 April 2007 (UTC)

A friend of mine had left some LSD tabs lying around and his cockatiel chewed some of it. The poor thing spent the rest of the day wandering in circles on the floor, occasionally fluttering a couple of feet into the air and squawking and spending a long time staring intently into the middle distance. He couldn't get near the bird to put it back in its cage - it absolutely freaked when he approached it. --Kurt Shaped Box 19:06, 8 April 2007 (UTC)

What a sad waste of acid [Mαc Δαvιs] (How's my driving?) ❖ 02:45, 9 April 2007 (UTC)

A waste, definitely, but I would call it a funny waste of acid. − Twas Now ( talk • contribs • e-mail ) 17:33, 9 April 2007 (UTC)

Reminds me of a Wild Party from my well-spent youth! I was helping my friend G--- get ready for the party... We had two bowls of cleaned marijuana set out with the chips and dip in the living room... Well, her dog ate most of one of them. About a whole ounce of weed. And he was a little guy, maybe 35 pounds... He was SO stoned. He laid in his dog bed all through the party and for most of the next day just looking at things like his paws and the light... And he could NOT stand up on the waxed kitchen floor. His legs would just slip out from under him. Poor thing! But he was fine after a day. --BenBurch 15:32, 11 April 2007 (UTC)

Does it help to be fat to play the tuba?

(following on from the question above) This may just be a TV/movie/cartoon stereotype but generally, whenever I see guys playing the tuba on TV, more often than not, they are the fattest guys in the orchestra. So, is there any real advantage to being fat when playing this instrument? --Kurt Shaped Box 07:44, 8 April 2007 (UTC)

You can lay it on your stomach? PitchBlack 07:58, 8 April 2007 (UTC)

I think it's just for the comedic effect. Tuba is often used in "funny" songs and a fat guy playing it makes it look even more ridiculous. Even if it's not a comedy in question, fat guy + tuba may have become such a strong stereotype that directors use it anyhow. --Nitku 17:24, 8 April 2007 (UTC)

That's the great unmade Jackass skit, isn't it? Johnny Knoxville hiding in some bushes and going 'Ooompah! Ooompah!' on a tuba whenever a fat guy walks past, in time with his steps, until someone punches him... ;) --Kurt Shaped Box 22:46, 8 April 2007 (UTC)

The first page of a Google Image Search for "tuba player" does not support a hypothesis that they are fatter than average. --TotoBaggins 17:34, 8 April 2007 (UTC)

Brainiac:_Science_Abuse had a section in one of their series to see if a obese or a underweight person would survive longest in given situations (heat, cold, wind, water, etc). I'd love to have seen which was best at surviving a tuba audition, although i suppose it would come more down to talent :p 80.229.228.229 19:36, 8 April 2007 (UTC)

It would be interesting to find out if the 'fat tuba guy' idea has become so universally accepted that they'd choose a fat guy over an equally skilled skinny guy at a tuba audition just 'because'... --Kurt Shaped Box 22:42, 8 April 2007 (UTC)

I played tuba when I was in high school (a few years ago). I don't believe we were more overweight than any other representative sample of the band (although we did have one HUGE kid). Actually, we tended to be a little more in shape in marching band (or so I like to think) since we had to lug that thing around. I suppose being LARGER (not necessarily fatter) could facilitate carrying it. It is possible that fatter kids may better play the tuba than other brass instruments due to the size of the mouthpiece; I had trouble playing anything with a mouthpiece smaller than a trombone/baritone mouthpiece, and I didn't even have a fat face. :) --Bennybp 21:01, 8 April 2007 (UTC)

Anecdotal, but one of the finest tuba players I know is a rather short ~90 lb woman. -- mattb @ 2007-04-08T22:50Z

I concur with Bennybp's assessment that it probably helps to be larger/stronger as far as transport goes, particularly when marching with a sousaphone. That's not to say that mattb's 90 lb. female tuba player couldn't carry a sousaphone, but on average you'd expect it'd be easier for someone with a large base and a few extra pounds of muscle and/or fat to not be overwhelmed by the 25+ pounds of instrument on their shoulder. As far as actual playing goes, I don't know enough about anatomy to say whether lung capacity has any real correlation to body size. I suspect not (at least as far as fat goes), but does anyone care to comment on that? Eric (EWS23) 12:35, 9 April 2007 (UTC)

I haven't seen it on TV, but at every high school and middle school band concert I've seen it's always the fat kids on the baritone and tuba. [Mαc Δαvιs] (How's my driving?) ❖ 02:43, 9 April 2007 (UTC)

Extinction

I saw the original 60's film "Planet of the Apes" tonight on TV, and got me thinking about extinction. And I thought:

1) Is there a reason why we should preserve species and not just let them die out?

2) Would it be possible to get DNA from living species now, and be able to create living copies of it in the future, incase they ever became extinct? (WHEN they become extinct)

If number 2 is possible, there should be a place/laboratory/museum where they have multiple DNA's from each species they were ever able to get DNA from (that is, if they haven't already). Any views for or against this idea? PitchBlack 07:57, 8 April 2007 (UTC)

1) That is a matter of opinion. Many people consider there to be an inherent value in biodiversity, others don't. However, ecosystems tend to be pretty finely balanced. So there remains the possibility that if we permit a certain species to die, its absence from the ecosystem could cause a chain reaction which could severely effect us humans. See, for example, the concern over the mysterious disappearing bees in the USA. [3]

Note: also see here: Colony Collapse Disorder. zafiroblue05 | Talk 00:27, 9 April 2007 (UTC)

2) We could try to clone some animal species by nuclear transfer, but would need a host egg and a mother in which to gestate the embryo. See here and here for info about current attempts at this and the problems they face. The Svalbard Global Seed Vault is being built at the moment to house seeds in case of a doomsday scenario and a similar Frozen Ark project has been launched in the UK for endangered animals. Rockpocket 09:30, 8 April 2007 (UTC)

You also need to take into account probably technical difficulties, consider the pandas, there aren't any physical barriers but it still is very hard to make them get it on.Bastard Soap 10:48, 8 April 2007 (UTC)

1) I can think of a number of reasons to keep non-competitive species around. For example, if a plant provides some sort of medicinal value, keeping it around might be very advantageous. However, realizing that a species is non-competitive pretty much means that it can never survive naturally.

2) We already pin hopes on this with the collection of cord blood. --Tbeatty 11:02, 8 April 2007 (UTC)

I don't think there is any reason to conserve organisms to keep them alive if they deserve to die and can't adapt, unless of course we need it. How much "reason" there is in the world is a matter of philosophy. [Mαc Δαvιs] (How's my driving?) ❖ 02:41, 9 April 2007 (UTC)

The problem with that, of course, is that when we realise that infact we did need a particular extinct species it will be too late. Rockpocket 04:16, 9 April 2007 (UTC)

If we didn't want to change nature we'd let whatever was set to die out, die out. [Mαc Δαvιs] (How's my driving?) ❖ 14:36, 9 April 2007 (UTC)

Emotional Crying

Why do we produce tears when we're in a strong state of emotion? (sadness, happiness, anger) I looked at the article on "tears" but all I see is that it's because of a "different chemical makeup" but it doesn't actually explain how or why it happens.

Like when our eyes get too dry, our brain notices and does doody-dah-bahbooloo and releases tears to lubricate them. So, when we're emotional, how is our brain reacting, and why does it ultimately react by making us tear?

Another question I think of when thinking of this is how can people focus and force themselves to cry? I'm occasionally able to do it, but me knowing that I, or others are capable of doing it does not let me know why it's possible, or why it's allowed to be done. PitchBlack 08:24, 8 April 2007 (UTC)

Not completely sure, but simply, such states of emotions activate the parasympathetic nervous system inducing secretion by the lacrimal glands.

Actors often "force themselves" to cry. I believe they do it by either getting sufficiently emotionally in tune with the script that they get affected by it, or by remembering something similar in their own lives that caused them to cry and letting that do the work. JackofOz 01:15, 9 April 2007 (UTC)

Just like how we have facial expressions, body language, and changes in speech, it is to let others know how we feel. That's what I've always thought. [Mαc Δαvιs] (How's my driving?) ❖ 02:39, 9 April 2007 (UTC)

Exactly right. We feel the emotions in our bodies, and express them (ie. communicate them to others) in various ways. JackofOz 03:58, 9 April 2007 (UTC)

Weird cause I just read an article that mentioned something related today. The relevant part is: "Crying is difficult to fake. Even actors have to generate some feeling before they cry. The Israeli evolutionary biologist Amotz Zahavi proposed that you can infer the honesty of a social signal by measuring the cost of the expression. Harvard's Marc Hauser, applying this principle to the eye, regards tears as the human equivalent of a dog rolling belly-up to show submission. "Unlike all of the other emotional expressions, tearing is the only one that leaves a physical trace," he says. "It blurs one's vision, therefore it's costly." Here. Recury 20:19, 10 April 2007 (UTC)

could electrons be splitted ?

is it possible to split an electron. if possible then how and what is emitted while electron splits up ? —The preceding unsigned comment was added by 202.56.7.139 (talk) 11:39, 8 April 2007 (UTC).

Good question. The answer is no, we have no evidence that it is ever possible to split an electron, and we have some good theoretical reasons to believe that an electron is indivisible. Our article on the electron says "The electron is in the class of subatomic particles called leptons, which are believed to be fundamental particles (that is, they cannot be broken down into smaller constituent parts)." Gandalf61 12:13, 8 April 2007 (UTC)

From experiments in particle accelerators it is known that electrons show no internal structure down to a size of 10^-18 meters. Icek 18:10, 8 April 2007 (UTC)

Also known as 1 attometer --172.130.96.204 22:24, 8 April 2007 (UTC)

    Thanks for answers . but as far as i know high energy photon shows
    pair production characteristics when they collide with any   
    particle .
    This characterastics proves that electron can be formed, then it 
    should be possible to split electron .

I don't follow your logic.. Capuchin 13:27, 11 April 2007 (UTC)

NOx Production

How many tonnes of NOx are produced daily by human activity? Tobes ^(talk) 13:26, 8 April 2007 (UTC)

[Nitrogen oxide] has some information on the subject but not number of that sort. Perhaps some of the links at the bottom can help you. Jon513 13:49, 8 April 2007 (UTC)

Atmospheric NO_x is at least sometimes measured in terms of just the mass of the nitrogen involved. The NO_x produced by human activity amounts to about 33 Tg of nitrogen per year,[4] which is equivalent to about 90,000 tonnes per day. MrRedact 16:41, 8 April 2007 (UTC)

DVD/CD Writing

Do CDs/DVDs write better if they are hot or cold? Becuase when i take them out i find they are always hot, but then again after extensive game playing they are also hot... —The preceding unsigned comment was added by 85.210.157.80 (talk) 15:26, 8 April 2007 (UTC).

Your question is similar to "does water hydrate you better if it is warm or cool? Because after it is in your belly it is always warm". The CD's are hot, in both cases, because they have just been spinning at incredibly fast speeds. You should always keep your CD's around room temperature. − Twas Now ( talk • contribs • e-mail ) 15:56, 8 April 2007 (UTC)

It's warm inside your computer's case (that's why it has fans) and the drive's motors, when in operation, also generate heat. Even when I'm not doing anything, my computer's CPU is still at a fairly steady 45°C/113°F. So while the drives don't deliberately heat the discs – indeed, excessive heat will shorten their lifespan, and very high heat may warp the disc and make it unreadable – there's not a whole lot that you can do about the ambient 'waste' heat they pick up. TenOfAllTrades(talk) 15:56, 8 April 2007 (UTC)

They are also heating up because there is a pretty bright laser shining on them. But whether the peculiar light sensitive dyes in writable CD/DVD's work better at different temperatures - I don't know. The fact is that once it's inside the drive it's going to be warm come-what-may so you don't really have a choice. Store them on their sides at room temperature though - keep them out of the sun. SteveBaker 17:23, 8 April 2007 (UTC)

I believe I've also read to store burned cds and dvds horizontally, because the ink can run after several years. And don't store them with too much weight on them, so spindles are a pretty good bet, since they keep them horizontal and the casing is what holds up whatever you stack. --Wirbelwindヴィルヴェルヴィント (talk) 18:45, 8 April 2007 (UTC)

...what are you talking about? Ink? Spindles? Or is this a joke? [Mαc Δαvιs] (How's my driving?) ❖ 02:38, 9 April 2007 (UTC)

I wouldn't call it 'ink' - it's a dye. SteveBaker 05:13, 9 April 2007 (UTC)

Do a google image search for dvd spindle to see what spindle is. Personally I dont thing spindles are ideal as you are stacking lots of discs, one over another, and there are spindles for 100 discs (also most I have are for 50 discs) and I dont see how can weight of 99 discs be beneficial to the bottom disc. Shinhan 09:40, 11 April 2007 (UTC)

Genetic disorder transmission

In the movie X-Men 2 (possibly not the most realistic portrayal of genetics, but still), one of the characters claims that the "mutant gene" (stupid name for a gene, given that any gene be mutated) can only be passed on by males. Of course, if the gene was on the Y-chromosome, then this would be possible, but since females do not have a Y-chromosome, they could not become mutants. So, more generally, are there are genetic conditions which can only be passed on by one sex, but expressed by either? Laïka 19:58, 8 April 2007 (UTC)

There are a few diseases mentioned in the article on mitochondrial DNA. Mitochondrial DNA is inherited only from the mother because the mitochondria of the sperm cell are destroyed after they enter the ovum (sometimes a paternal mitochondrion can survive, but this is rare in humans). Icek 20:53, 8 April 2007 (UTC)

Outside mitochondrial DNA, no. Genotypically speaking, if it can be expressed by either sex it can "be passed" on by either sex (though there are some hypothetical scenarios involving sex-specific uniparental disomy though could confound that, I suppose). However, there are some phenotypes that could result in that sort of scenario. For example, a autosomal-dominant gene mutation that had a sole phenotype of extremely abnormal oocyte development would - in practice - only ever be passed down the male germline since females that expressed it would be infertile. Similarly, a dominant gene that had a phenotype resulting in abnormal semen composition might only be passed on by females, since males that expressed it would be infertile but the female phenotype might be rather inconsequential. There likely are such disorders, though I can't think of any specific examples off the top of my head. Come to think of it, any X-linked recessive disorder that resulted in death in males before puberty would essentially have the same result: both sexes express the allele (at least in some cells) but only females will pass it on. Rockpocket 22:02, 8 April 2007 (UTC)

Natural Environment

I regret that such an important concept received such a poor article (I myself don't have any knowledge to improve it). It seems that the expression "natural environment" has two different meanings in the article:

1. In the opening paragraph, "the natural environment" (with definite article) is described as all natural things on earth.
2. in the Terminology section, "a natural enivronment" (with indefinite article) is described as any region or landscape with little human intervention.

These two meanings are quite different from one another. Do they really exist in parallel? If someone could improve the article and make things clearer, that would be great. Gidip 20:08, 8 April 2007 (UTC)

Is the problem with the use of "the" vs "a"? Or whether nature includes humans or not? Pfly 06:33, 9 April 2007 (UTC)

The problem is that two different meanings are described, but there is no clear distinction, and the article doesn't clearly mention that there are two different meanings. So, are there really two different meanings, or is it just a broad term, without any clear definiton? Or maybe I've misunderstood everything? Gidip 12:51, 9 April 2007 (UTC)

To me it sounds like the first definition is a general all-inclusive one, and the second is for specific cases, but otherwise essentially the same in meaning. Like, to take a different example, "the human population" meaning all people, while "a human population" being a specific subset. Either way it's still human populations, or natural environments. After all, the planet is an environment -- a region or landscape in a broad all-inclusive sense, no? Pfly 03:17, 10 April 2007 (UTC)

Vinageroon

Looking deadly is an over-rated survival strategy - this little guy is doing just fine with cuteness. Rockpocket 01:14, 9 April 2007 (UTC)

I am looking for info. on a Texas arachnid known as the "vinageroon". Can find nothing on them, but know they exist because have seen them. They exist in the desert areas along with the scorpions. The common name comes from their toxin made up of acetic acid.

Vinageroon Greglocock 21:18, 8 April 2007 (UTC)

That's a horrible-looking beast! You would think that after 4x10⁹ years of survival of the fittest everything would look that deadly. Thank God for koala bears. :) --TotoBaggins 01:07, 9 April 2007 (UTC)

They're not bears, but give them 4x10⁹ years and they may yet evolve into bears. But probably not. JackofOz 01:11, 9 April 2007 (UTC)

Wow, that is one awesome bug!! Yeah I know it's an arachnid, but I'm calling it a bug. Anchoress 03:52, 9 April 2007 (UTC)

Oh God, how'd you like to find that one in your bed when you wake up? Oh, and look, they spray acid! a combination of acetic acid and octanoic acid when they are bothered. The acetic acid gives this spray a vinegar-like smell, giving rise to the common name vinegaroon. Other species spray formic acid or chlorine. [Mαc Δαvιs] (How's my driving?) ❖ 14:35, 9 April 2007 (UTC)

A question on " self "

A little blurb came up in my mind a few years ago, and is still with me to this day.

If who I am, is formed (in simpel terms) by my neural net. And this neural net is constantly changing, adapting, reconnecting and restructuring itself. Then aren't I in a fact being reborn over and over again? Only with little changes in stead of large ones? Changes so small that nobody would doubt that PvT is still PvT? Countless of other PvT's have existed and died, are no longer here. Yet nobody mourns them.

So if I am in a constant state of flux then when am I me? And what then does it mean to die?

Are there any branches of science/philosophy that touch this subject? I've been trying to read the article on the philosphy of mind and such. But they are rather, bulky.PvT 21:36, 8 April 2007 (UTC)

Philosophy of the mind is all about questions on this — you are essentially asking questions about the nature of consciousness and its relation to the self. But yeah, it's bulky, if bulky you mean "full of specialized terminology and obscure concerns based on very old debates some of which are still relevant and some of which seem less so." As for branch of science, cognitive science is an interdisciplinary approach to questions like this, building on philosophy, linguistics, neuroscience, psychology, etc. You might try Steven Pinker's How the Mind Works, which is a readable popularization of cog sci and phil of the mind. --24.147.86.187 22:33, 8 April 2007 (UTC)

There's also Self (philosophy), which I haven't read fully but looks at first glance like it should probably be merged with Self (psychology). --Allen 02:40, 9 April 2007 (UTC)

Wow, and there's Self (sociology) too. I'm skeptical about whether we can or should separate these different senses of the word. --Allen 02:45, 9 April 2007 (UTC)

If who I am, is formed (in simple terms) by my neural net. --that's a mighty big if. Pfly 06:44, 9 April 2007 (UTC)

Really. Who I am is formed by my butterfly net. − Twas Now ( talk • contribs • e-mail ) 06:55, 9 April 2007 (UTC)

You might be interested in Ship of Theseus, this is an old paradox... ^tucker/_rekcut 22:28, 9 April 2007 (UTC)

That is relevant to gradual replacement of parts of the physical body, until the original body is entirely replaced. However, who a person "is" is, imo, a considerably broader question than just their physical body. JackofOz 00:33, 11 April 2007 (UTC)

Buddhisim addresses this type of flux as well, the Sarvastivada sect in particular (http://en.wikipedia.org/wiki/Sarvastivada). You may also want to read "The Nature of Consciousness and the Chain of Causation" from Majjhima Nikaya or 'the Medium group' of Discourses found in the Tripitaka or 'the Three Baskets' (though I first read it in an Introductory Txt Book for an Asian Religons course). Most translations of this are kind to those of us without a background in Pali.AggieAnnieM 09:17, 11 April 2007 (UTC)

Intelligent, non-Terrestrial Life?

Does it exist somewhere in the universe?--172.131.75.193 22:25, 8 April 2007 (UTC)

Nobody knows. At the moment all we have are guesses, but there is no solid evidence of it as of yet, and no strong reason to think that intelligent life has existed simultaneously with the intelligent life on this planet (i.e., did not evolve sentience and then kill itself off as the human race has threatened to do at many points in its feeble and geologically-brief existence). --24.147.86.187 22:30, 8 April 2007 (UTC)

The International Space Station is manned isn't it? Vranak

Yeah, but I'm pretty sure life didn't evolve on it :). Splintercellguy 00:14, 9 April 2007 (UTC)

As 24 says, no one knows. There is no evidence that there is or has been intelligent life elsewhere in the universe. For that matter, there's no evidence for extraterrestrial life of any kind, aside some from some controversial, unconfirmed claims of Martian microbes. That being said, the universe is a huge place: with some 200 billion stars in our galaxy, and some 100 billion galaxies in the visible universe, many people the chances are very high that not only life, but intelligent life would evolve elsewhere in the universe. Of course, even if it did, the enormous distances might preclude any contact between our species. — Knowledge Seeker দ 03:37, 9 April 2007 (UTC)

Obviously - we don't know. I strongly suggest you read about the Drake equation. That is a rational effort to put together an estimate for the probability and number of intelligent races in the universe. The trouble is that this equation has an awful lot of unknown terms in it (eg What is the average number of earthlike planets orbiting each star? We don't know because our technology isn't good enough to detect earthlike planets orbiting other stars.) - depending on what semi-informed guesses you plug into that equation, you can get answers anywhere from it being very unlikely to there being tens of thousands of extraterrestrial civilisations out there. SteveBaker 05:10, 9 April 2007 (UTC)

Unknown Plant Picture

Can this photograph be identified? Thegreenj 22:42, 8 April 2007 (UTC)

No idea, but googling 'blue flower' sure turns up a lot of beautiful pictures. I'd thought it might be ragweed, but I guess not. Anchoress 00:08, 9 April 2007 (UTC)

Could it be lupin? The pic in the article doesn't look the same, but some of the internet pics do. Also check lobelia, spiderwort and pickerel weed. Anchoress 00:53, 9 April 2007 (UTC)

Looks to be in the family Boraginaceae; good chance of Echium genus. try those as search terms.Polypipe Wrangler 01:54, 9 April 2007 (UTC)

I have uploaded a new photograph just for identification purposes. Thegreenj 00:10, 10 April 2007 (UTC)

It really looks like pickerel weed, which I suggested above. Look at the similarity between the leaves (although the article has only a drawing). Anchoress 01:02, 11 April 2007 (UTC)

Morphological Crystallography,the Tschermak forms and the 48 simple forms in mineralogy

• Hi ,i have been astonished by this subject on my mineral science class last monday about this topic.
• What are the Tschermak forms? , are they related with Gustav Tschermak von Seysenegg? And what are them in the first place?. Does they only belong to the isometric form (crystal forms classes) system on morphological crystallography?--HappyApple 23:54, 8 April 2007 (UTC)