Wikipedia:Reference desk/Archives/Science/2006 September 21

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September 21

Hurricanes and Tropical Storms in Europe

Here in Spain we are all watching the news with ex-Hurricane and now Tropical Storm Gordon about to arrive in Galicia (frankly this is seeming surreal, I believe it is heading for France/South England afterwards). 1) Is this a serious indication that something is going very wrong with our climate? 2) Is it possible that in the near future we will see major hurricanes hitting the coasts of Spain/Portugal/France/UK/Ireland and killing us? Thank you in advance for information even if worrying ==ALang==

Hey ALang - storms crossing the Atlantic is nothing new, the remnants of Hurricane Floyd created the Great Storm of 1987 (killed about 20 in the UK). They don't usually get this far with any intensity, but whenever there's a big storm we get the tail end of it, it just usually manifests itself in the form of a few clouds. The Atlantic would need to get significantly warmer in order for such storms to form over it with any reliability or regularity. We'll probably die due to the Azores falling into the Atlantic and creating a huge tidal wave long before hurricanes threaten us in a big way :) --Mnemeson 00:34, 21 September 2006 (UTC)

Oh, and it turns out we have an article on European windstorms - hopefully another like 1362 won't come along soon. Okay, much of my answer could be technically right, due to use of the word 'hurricane', which has a precise definition, but read the article on windstorms, it's a lot more helpful. I'm gonna go off and sing 'Captured in a windstorm'... --Mnemeson 00:40, 21 September 2006 (UTC)

Though, of course, it should be mentioned that it could be an indication of a changing climate, although not (by itself) a particular reliable one. There are still many people who argue that any irregularities in climate that have appeared recently could merely be signs of an active weather process that cycles over decades or centuries, though do you really want to risk letting them be wrong?  freshofftheufoΓΛĿЌ  00:55, 21 September 2006 (UTC)

Hurricane Florence almost hit Newfoundland the other day, that's pretty far north for a hurricane. User:Zoe|(talk) 02:48, 21 September 2006 (UTC)

A single event is no indication of climate change, unless it is something that could normally never have happened, and 'never' is a big word. It would take several events to draw such a conclusion, such as not one hot summer but several in rapid succession, as we are experiencing in the last decade or so (actually, almost every summer is a record breaker by pre-1990's standards - what more proof could one wish for?). As for your second question, hurricanes are being reported in places where there never were any before, such as off the Brazilian coast (or thereabouts - vague recollection). I'm no expert, but I believe hurricanes are caused by temperature differences between sea and air and with the weather becoming more erratic unexpected things might happen. Hurricanes in Europe is just one possibility. Droughts and floods, which are very likely to become more frequent are a much bigger threat. DirkvdM 09:31, 21 September 2006 (UTC)

Hurricanes are caused by the latent heat of condensation over warm sea waters, unlike polar lows, a.k.a cold fronts, which depend on thermal differences between air masses. Titoxd^(?!?) 03:20, 25 September 2006 (UTC)

Yeah, you are talking about Cyclone Catarina, which is the only observed tropical cyclone to reach hurricane intensity in the Saffir-Simpson Hurricane Scale to form in the South Atlantic (although hurricanes impacting South America aren't rare, we have a featured list about it). Hurricane Ioke hit Alaska the other day, albeit as an extratropical cyclone. About Europe, though: it seems we are forgetting Hurricane Vince, which is the only hurricane to impact the Iberic Peninsula in record; however, hurricanes hitting Great Britain after extratropical transition are not that rare. Just have a look at the 1985-2005 cumulative cyclone track map and you'll see that they aren't that rare. Titoxd^(?!?) 03:20, 25 September 2006 (UTC)

Rubbing Alcohol and Blindness?

When I look at a bottle of rubbing alcohol it says: "Do not consume (no kidding!) Consumption may lead to blindness or death". I can accept without really understanding that doing such a stupid thing as drinking wood alcohol can, along with a whole bunch of other awful things, kill you. I've just always been curious as to why "blindness" in particular is singled out as a very possible result. What is the particular and to me, rather peculiar connection between consuming rubbing alcohol and blindness? Loomis 02:30, 21 September 2006 (UTC)

This is interesting. I typically associate rubbing alcohol with isopropyl alcohol (the Wikipedia article mentions ethanol preparations, as well). However, neither are classically associated with blindness. I associate blindness with methanol (wood alcohol) because exposure commonly results in blindness. So, I can't answer your question. However, if the bottle actually contained methanol, the warning would be apt because it commonly damages the optic nerve. InvictaHOG

Yeah IPA doesnt blind you but can cause other problems (even sniffing it is bad). I remember seeing or hearing the COSHH data on it. Is this the same thing as surgical spirit?--Light current 02:54, 21 September 2006 (UTC)

Ok, I hadn't realized that there were different kinds of rubbing alcohol. Apparently, I was wrongly using the terms "rubbing alcohol" and "wood alcohol" synonomously. In any case, I'm concerned with the type that is apparently connected to blindness, which would apparently be methanol, or wood alcohol. I'm still curious as to why blindness is a particularly specified danger. Loomis

blindness is one of the permenant non-fatal effects of consuming methanol, and takes very little. maybe thats why? and i remember reading about a study where they placed 'warning: fatal' and 'warning: causes permenant disfigurement' on bottles, and they found the latter a more effective deterrent. Xcomradex 04:19, 21 September 2006 (UTC)

The incidence of irreversible blindness seems to be high among survivors of methanol poisoning. Every year you can read about incidents worldwide caused by drinking home-made spirits with toxic amounts of methanol; many victims remain blind or partially blind for the rest of their lives. It's probably not methanol itself that is toxic, but one of its metabolites, specifically formaldehyde and formic acid. Blindness may result from accumulation of formic acid inside the retina.---Sluzzelin 09:30, 21 September 2006 (UTC)

To answer what I think is the actual question here ("What is it about methanol that causes blindness, and not, say, seizures, or skin discoloration, or burning of the esophagus, or any number of other possibly disfiguring or dangerous consequences?"), I'll point to our methanol article, and the "Health and Safety" section in particular, and this quote: "It is toxic by its breakdown by the enzyme alcohol dehydrogenase in the liver by forming formic acid and formaldehyde which cause blindness by destruction of the optic nerve." Note to self: Improve that sentence. It then links to an article in the DoE's "Ask a Scientist" archive with some better details. You can keep asking "yeah, but why?" all the way down, but hopefully this is a sufficiently substantive answer. An aside, one thing I've always found interesting is the treatment for methanol poisoning: getting the patient drunk on ethanol (although usually IV, not the fun way). -- Plutortalkcontribs 12:03, 21 September 2006 (UTC)

Thanks, Plutor, for finally identifying my actual question, in a way I was apparently unable to. Loomis 00:19, 22 September 2006 (UTC)

Of course, now that we have fomepizole, we don't have to worry about IV ethanol. InvictaHOG 17:28, 21 September 2006 (UTC)

Worry? Who was worried? I was looking forward to it, myself. -- Plutortalkcontribs 10:38, 22 September 2006 (UTC)

Shape and Finish of granite rocks in Texas Canyon in Arizona

Recently we drove through Texas Canyon on I-10 near Benson, AZ. The rocks in the canyon are very interesting and one can't help wondering how they were shaped. None of the rock have sharp edges; they rounded and smooth and give the appearance of being finished either by man or by nature. My sister-in-law says the rocks were rounded over the eons by rushing water. I'm not sure how they were finished so smoothly but suspect they where shaped by nature. They appear to have been formed as giant bubbles of lava or magma. Can anyone help us conclude how these beautiful rocks came to be??

Are the rocks attached to the ground or loose ? StuRat 11:55, 21 September 2006 (UTC)

Texas Canyon, AZ

well, 6000 years ago they magically appeared from the void ;-) more seriously, do they look like the Moeraki Boulders in New Zealand? Xcomradex 04:15, 21 September 2006 (UTC)

Granite is a volcanic rock, but it also sounds like they may have been ground to me. I can think of two likely ways:

• They might have been run over by glaciers (during an ice age) and dragged underneath them, being ground against other rocks in the process.

• They might be in an area subject to massive flooding on a regular basis at some point in the past. The boulders would bounce around on the ground underneath a torrent of water, and be ground down in that manner. StuRat 05:23, 21 September 2006 (UTC)

If the image we have of Texas Canyon is any indication of the rocks you're talking about, I'd say sandy wind (i.e. sandstorms) would do the trick.  freshofftheufoΓΛĿЌ  06:07, 21 September 2006 (UTC)

Some of those rocks have a rather erotic shape, maybe I should open a rock porno site, LOL. StuRat 11:53, 21 September 2006 (UTC)

There appears to be almost no geologic information on this. Since it is called a canyon, and they loosely use the term 'granite', I would assume that water was the main smoothing agent. --Zeizmic 12:02, 21 September 2006 (UTC)

It looks rather like a large lady reclining. THe rock at the top is the head.--Light current 15:12, 21 September 2006 (UTC)

According to this, it's not granite! Rather, it's quartz monzonite. Water does the trick quite well. --jpgordon^∇∆∇∆ 16:55, 21 September 2006 (UTC)

The easy answer is "erosion". The hard answer is what type of erosion (wind, water, ice?). --Fastfission 20:41, 21 September 2006 (UTC)

Much of the rounding is a result of exfoliation, a common development in granitic rocks (quartz monzonite is not really very different from granite). The final bits of smoothing probably result mostly from wind and some flash flood erosion, as suggested above. No glaciers in this area. The rocks in Texas Canyon are roughly 70 million years old (the time they were forced into pre-existing rocks as molten magma - Granite and quartz monzonite are not volcanic - meaning erupted onto the earth's surface; they solidify hundreds or thousands of feet below the surface, allowing their crystal grains to grow to visible sizes.). Cheers Geologyguy 17:59, 22 September 2006 (UTC)

• Well, it is actually quartz monzonite porphyry, broken up by spalling and sheeting. ^{Chronic, Halka (2002). Roadside Geology of Arizona. Missoula, Montana: Mountain Press Publishing Company. ISBN 0-87842-147-5.} Titoxd^(?!?) 04:06, 26 September 2006 (UTC)

Antimatter

I have read the article on antimatter and for some reason I still dont understand the process in which they make it. Please someone explain to me the process so I can understand it fully. Thanks in Advance for all your help.67.126.143.78 04:32, 21 September 2006 (UTC)

Looks to me like the antimatter article's main weakness is that it doesn't explain where the antiprotons come from. I don't know the details myself, but here are a few diagrams [1] [2] and a PDF of a review [3]. And here's a cool video showing what happens after the antiproton is created. --Allen 04:46, 21 September 2006 (UTC)

Antiproton describes one way of creating them. (Ain't Wikipedia wonderful?) It takes a lot of energy, while positrons (i.e. anti-electrons) are relatively easy to find, even occurring naturally. There are also antineutrons, if you're feeling ambitious. The big problem is keeping them around long enough to form antimatter atoms, since they have the annoying tendency to encounter their normal matter counterparts and vanish in a burst of energy. I believe they use magnetic fields and near vacuums to accomplish this feat. Clarityfiend 04:51, 21 September 2006 (UTC)

It is kind of confusing. The physicists do some particle physics equations to determine what happens when they break apart particles, and smash them together. They end up trying to do what is intheory experimentally and isolate the antiprotons from the mix with penning manipulation. — [Mac Davis](talk) (SUPERDESK|Help me improve)05:29, 21 September 2006 (UTC)

Do anti-matter fall upwards?

Do anti-matter have negative kinetic energy?

Ohanian 11:32, 21 September 2006 (UTC)

No to both of the above. You're maybe thinking of exotic matter.

Really it's all about conservation of energy and E=mc².

See http://math.ucr.edu/home/baez/physics/ParticleAndNuclear/antimatterFall.html "Does antimatter fall up or down?" "In theory, antimatter dropped over the surface of the Earth should fall down. However, the issue has never been successfully experimentally tested. ..." from the Physics FAQ --GangofOne 02:03, 22 September 2006 (UTC)

Do herons swim?

Do Grey Herons swim? My bird books (and Wikipedia) don't say they swim, but they don't deny it either. A friend of mine said he saw one swimming on our local pond, but I think it is more likely to have been wading, or else he saw something else.--Shantavira 09:59, 21 September 2006 (UTC)

I have no scientific information, just original research. For what it's worth: I frequently watch grey herons hunt in a river near where I live. On several occasions I've seen one of them gliding over the water, and then landing on top the water and floating for a few seconds before taking off again. It didn't look like it was wading, and the water seemed too deep and the current too strong for that. ---Sluzzelin 10:37, 21 September 2006 (UTC)

Do they swim? i would say the most likely answer is no. Animals swim mostly for food or to escape. Unless the Grey Heron needs to swim for food, it's very unlikely to swim since it is able to fly. And it can cool itself by wading - which it does, and has no need to swim. If the Grey Heron naturally swim for any other reason, it would be a behavioural oddity, and would most likely be well-noted.

a related question would be whether they can swim. In which case i'd say yes. Some animals that don't live in water can swim naturally, others can't at all. Most animals can to a certain degree --> that is, they're not good swimmers like a penguin, but they're not going to drown. Considering how swimming is quite common amoung birds - i'd say a bird that wades and eats fish will most likely have some ability to swim. So it's not going to kill it self if it accidentally slips while wading, or accidentally wades too far into deep water.

if you're really wanting to find a sure answer, i recommond doing some reading about Ciconiiformes, the order that the Grey Heron belongs to. There'll probably be information avaiable about Ciconiiforms behaviour in general. And if you find textbooks saying Ciconiiforms can/do swim in general, then i think you'll have your answer. Either that or do some general reading about bird behaviour. Simply because i doubt anyone's gone out to scientifically observe every species of bird and see whether they can/can't and do/don't swim, and Grey Heron's aren't anything particularly special. Yaksha 14:34, 21 September 2006 (UTC)

What about this picture?---Sluzzelin 14:42, 21 September 2006 (UTC)

As waders, their feet are not webbed. What your friend probably saw was the heron floating. It was probably not using its feet in any way, as they would be pretty useless in propulsion. Also, if it is a "pond", that sounds shallow enough to wade. --liquidGhoul 14:40, 21 September 2006 (UTC)

I think the picture clinches it. Thanks Sluzzelin. --Shantavira 17:44, 21 September 2006 (UTC)

There's a heron plague in Amsterdam and indeed I see them regularly around where I live, next to a canal. All sorts of birds swim in the water, but I've never seen a heron do that. They fly by or stand on houseboats, but never in the water, which is about 2 m deep. DirkvdM 09:00, 22 September 2006 (UTC)

Here's another picture, and the same picture magnified. I did some more research on hobby ornithologists' websites, and there are numerous reports of swimming grey herons. That being said, almost every mention is accompanied by the expression of surprise at seeing such a sight. So it's a common uncommon phenomenon. ---Sluzzelin 16:22, 22 September 2006 (UTC)

matter

what are the different changes that take place in matter? waht are the signs or evidences of a chemical changes? what are the examples of physical changes and chemical changes? why?

One example is the change in synaptic strength that takes place in your brain matter when you actually try to answer these questions by reading textbooks and the like. This particular change is also called learning. Not much changes on the level of synaptic strength when you merely copy any answers that might be posted here. ---Sluzzelin 11:22, 21 September 2006 (UTC)

That was both scathing and clever. Hyenaste ^(tell) 18:34, 22 September 2006 (UTC)

Copper sulfate

As a crystal of copper sulfate is heated, does its weight increase or decrease ?

The mass of it would not change. The weight of it would not change. See conservation of mass, and next time do your own homework. — X [Mac Davis] (SUPERDESK|Help me improve)18:25, 21 September 2006 (UTC)

Not to sound stupid but doesn't copper sulfate crystal (blue) involve H2O in some way and heating it would evaporate the H2O and leave white copper sulfate. Or am I messing up high school chem again? 62.194.90.163 18:37, 21 September 2006 (UTC)

Yes, some Copper Sulfate is really a hydrate (and is blue). If heated the Hydrate (water) is driven off and the mass will decreate as a consequence. The color will change also.

The molecules having been accelerated, Relativity predicts a small increase in mass. (Too small to matter.) Of course, some of them might evaporate, or otherwise change state. (Not too small to matter.) -- Fuzzyeric 19:38, 21 September 2006 (UTC)

I did this exercise in high school chemistry. Water molecules are driven out of CuSO₄ • 5H₂O as it is heated, so it does in fact lose mass. Hyenaste ^(tell) 20:20, 21 September 2006 (UTC)

i second Hyenastes answer. Xcomradex 21:39, 21 September 2006 (UTC)

OTOH Anhydrous copper sulfate is white and would not lose any weight as there is no water in it.--Light current 22:06, 21 September 2006 (UTC)

Depends on how much you heat it, and for how long, really. --Serie 23:21, 21 September 2006 (UTC)

You mean:

At 650 °C copper(II) sulfate decomposes into copper(II) oxide (CuO), Sulfur dioxide (SO2) and oxygen (O2).? Well yes!--Light current 23:36, 21 September 2006 (UTC)

• Still, the weight or mass of copper sulfate wouldn't change. It would be the mass of the remains after heating that changes compared to the starting material. But if you put evaporated water and copper sulfate together, you still have conservation of mass. - Mgm|^(talk) 23:25, 21 September 2006 (UTC)

Well of course you do!.But this is obviously a homework question where the simple answer is wanted by the teacher!--Light current 01:36, 22 September 2006 (UTC)

Hepatitis?

Sorry about the graphic nature of this question, thought about it, and theres no "nice" way to put this (hows that for an intro?). Anyways, after a bowel movement, when wiping sometimes either the toilet paper is lousy or ill be wiping to vigrously maybe. But Ill start to bleed. Now is there any risk of left over fecal matter entering my blood stream through the open cuts? Cant you get like hepatitis from fecal matter entering your blood stream? or E.coli or something?

Thanks!!!

Very little risk. I suggest using a wet wipe or putting moisturizer on the TP. That allows you to get clean without creating so much friction. StuRat 17:14, 21 September 2006 (UTC)

I will echo this. Can certainly happen - you can get all kind of horrible nasty infections from bacteria (such as E. Coli) in your bowel entering your blood stream. However, the mechanism you describe is low risk. Furthermore, hepatitis is not caused by bowel bacteria - the most common forms are due to viruses that are transmitted by other people to you. InvictaHOG 17:26, 21 September 2006 (UTC)

Just make sure you're not sharing your toliet paper! :) I would see a doctor about it. You bleed everytime?? — X [Mac Davis] (SUPERDESK|Help me improve)18:29, 21 September 2006 (UTC)

It is true that the various hepatitis viruses can be transmitted in feces. However, if it is your feces that is carrying the hepatitis, you are not at risk for transmission, since you already are infected in that case.

Regardless, any bleeding in the digestive tract from the mouth to the anus has the potential to cause a transient bacteremia-- i.e., a brief period where bacteria circulate in the bloodstream. For most people, this poses little risk, and the bacteria are quickly cleared from the circulating blood. In fact, transient bacteremia is a common event for almost everyone. However, those people with certain predisposing conditions (e.g. rheumatic heart disease, mitral valve prolapse with regurgitation, heart valve prosthesis, joint prosthesis, or history of glomerulonephritis, can develop serious systemic infections as a consequence of bacterial seeding.

By the way, although rectal bleeding is commonly caused by benign conditions such as hemorrhoids or anal fissures, all instances of blood in the stool should be treated as suspect until proven otherwise--Mark Bornfeld DDS 18:34, 21 September 2006 (UTC)

shark's name

I am looking for the name of a type of shark. I was wading here in Charleston, SC and I thought I saw a very large catfish swimming around my legs. I reached in and grabbed it. When I pulled it out of the water, I noticed it had no scales, so I assume it was a small shark. It was gray, had a small dorsal fin, and a rather flat nose/mouth (not pointed like great whites). I thought it was a catfish because it had long "whiskers" coming out of the corners of its mouth. I've been searching through shark images on Google, but I can't find anything that looks like it. Any ideas? --Kainaw ^(talk) 20:30, 21 September 2006 (UTC)

Your description is vague, and it could have been several species. An easy way for a layperson to tell a shark from a bony fish is by looking at the gills. If it has multiple gill slits, it's probably a shark; if it has a hard round cover over the gills (the operculum), it's probably a bony fish. If it was indeed a shark, it might have been a juvenile nurse shark, which has barbels like a catfish, or perhaps a species of catshark. I assume this was in the ocean, not in fresh water. --Ginkgo100 ^{talk · e@} 20:40, 21 September 2006 (UTC)

Thanks. It definately was a nurse shark. I saw in the article that it has a "sluggish behaviour", which is probably the reason I was able to catch it with my hands so easily. I guess it was a juvenile as it was only about 2 feet long. Knowing the species, I've been able to assure my wife that it is not dangerous. So, she isn't bothered by going back in the water. She wouldn't take my argument: If I was able to pick it up, look it in the face, then let it go and not get bit, it must not be a dangerous shark. --Kainaw ^(talk) 00:29, 22 September 2006 (UTC)

Bruce. Remind me not to sell you medical insurance (Pick it up. If it doesn't bite your face off, it must not be dangerous???) Clarityfiend 17:08, 22 September 2006 (UTC)

empirical formula

ok i have this problem:find molecular formula of a fully combusted hydro carbon that produced 7.2 grams of water and 7.2 liters of co2 at stp. wats the empirical formula. ok so idivided 7.2 liters co2 by 22.4 to get .321 moles and 7.2 g h20 by 18.02 toget .4 moles then divide both by .321 to get 1 co2 and 1.25 h2o and muliply both to get 4 as coefficient of co2 and 5 coefficient of h20. therefore the empirical formula is c4h10. Can somone please tell me if im right and if not how to doit correctly and how to get the grams of o2 required to completely combust the hydrocarbon and molecular formula of hydrocarbon. please help im stuck for an hour --69.140.210.163 20:36, 21 September 2006 (UTC)

Excellent! Now you need to work out the number of moles of butane, write the balanced equation of its complete combustion to get the molar ratio of butane:oxygen, work out the moles of oxygen and then multiply by 32. The formula you have is the molecular formula as well as the empirical formula, because you can't have an odd number of hydrogen atoms in a hydrocarbon. --G N Frykman 20:59, 21 September 2006 (UTC)

Advantages of skimmed milk?

Is skimmed milk to prefer to semi-skimmed milk or whole milk? The fat is mostly saturated isn't it? But if you take away the fat, what happens to the fat soluble vitamins in the milk? Jack Daw 21:16, 21 September 2006 (UTC)

Vitamin A and D are fat soluble. Skim milk is allowed to contain up to 0.5 grams of fat per cup. That amount would carry vitamins A and D and allow for their absorbtion. Vitamin A, however, may be negatively effected by UV light in transit. Regardless of the saturation of the fat with hydraogen, fat has a LOT of calories, and has few positive nutritional benefits. (source: http://healthletter.tufts.edu/issues/2003-04/asktufts.html) JBKramer 21:26, 21 September 2006 (UTC)

It has a very clear nutritional benefit and you have already mentioned it. It has lots of calories. It is only in some modern cultures where getting too many calories is a problem. Rmhermen 01:51, 22 September 2006 (UTC)

And, of course, nearly everyone here (English speakers with Internet access) is in one of those cultures. StuRat 03:38, 22 September 2006 (UTC)

Some fats and fatty acids, like omega 3 fatty acids, are healthy. However, these tend to be found in plant and fish products, not in meat or milk. So, fat from those sources should be limited. StuRat 03:35, 22 September 2006 (UTC)

I'm an English speaker with Internet access and I consider energy in my food a good thing as long as I burn as much energy. If you're a lazy bastard who eats loads of junk food (irrespective of whether you speak English or have internet access), maybe milk won't be good for you unless it's deformed by extraction of much of its nutritional value. Then again, if you value your health so much that you worry about that, then why don't you change your lifestyle such that drinking proper milk won't harm you? That would make sense, wouldn't it? Eg sell the car and get a bike (save the planet in the process). Btw, energy is properly expressed in joules. The calory is archaic. DirkvdM 09:14, 22 September 2006 (UTC)

Certainly there are many people in the world who have to spend most of their time thinking about what they can do to get enough calories every day, but I can't believe you have to worry about that, any more than you have to worry about not being able to get enough sodium each day. On the contrary, you would have to make a serious effort to keep from getting enough calories and sodium each day. StuRat 15:14, 22 September 2006 (UTC)

There's more to the question of fat consumption than lack of exercise. Even someone who gets a proper amount of exercise still will benefit from a diet high in "good fats" and low in "bad fats", like saturated and trans-fats. Since milk is high in bad fats, it then makes sense to remove some of them, or limit your milk consumption, while simultaneously increasing your consumption of good fats from other foods, like fish and nuts. StuRat 14:53, 22 September 2006 (UTC)

And, unlike some other low fat foods, where they use some rather questionable chemistry on the food, skim milk just has the cream skimmed off the top, so I would hardly call it "deformed". StuRat 15:09, 22 September 2006 (UTC)

Milk has the unique characteritic of being food that is expressly meant to be food. So whatever is in it, common sense dictates that it must be healthy. I'm not going to let dietists double-guess evolution for me. DirkvdM 07:31, 24 September 2006 (UTC)

Human milk is made to be healthy for human babies, and cow milk is meant to be healthy for calves. Neither are meant to be healthy for human adults. Babies, and particularly calves, need to put on a lot of fat quickly, while human adults mostly already have an adequate layer of fat, so don't need the high fat diet provided by whole cow milk. Also, there are other foods meant to be food, such as berries. They want animals to eat them to spread the nicely fertilized seeds, and providing good nutrition for animals is the best way to get that to happen. A nice example of symbiosis. StuRat 09:47, 29 September 2006 (UTC)

Point light displays

Do point light displays (such as this one) go by any other name? I can't find an article for them on Wikipedia, so I want to start one. However, I'm afraid an article already exists by another name. Thanks, --JianLi 21:26, 21 September 2006 (UTC)

• I've made a stub, point-light display, to be redirected if anyone finds an existing article. --JianLi 21:50, 21 September 2006 (UTC)

unidentified insect, need help

I have recently come across a very strange looking insect in my basement. I live in western North Carolina, U.S.A. Anyway, the insect looks to be related to the grasshopper. It is brown in color. It's a little more compact than the ordinary grasshopper. It doesn't appear to like daylight. It's not a cricket. The insects back legs are very big, almost "meaty". And here's the strange part: It leaps backwards! It jumps the opposite direction from the direction it's head is pointed. I asked a neighbor what it was, and he called it a back-hopper. Sadly, I have found no documentation on such an insect. I know it exists, therfore I'd like to be able to identify it, get some information, and even a photo. Someone has also told me that it is a wood-destroying insect so it has raised my interest that much more. Please forward any information on the subject.

Thanks, Dean

If you have a photo, you can try asking "BugGuide.net" or "What's that Bug". http://www.boingboing.net/2006/07/24/online_bug_identific.html --Kjoonlee 01:28, 22 September 2006 (UTC)

If it looks like a grasshopper, it might be in the Orthoptera. (Orthoptera includes "crickets, grasshoppers and katydids" according to WTB. I'll try having a look through the Orthoptera articles. --Kjoonlee 01:40, 22 September 2006 (UTC)

I had a look, but couldn't find anything mentioning pointed heads or backward leaps. --Kjoonlee 02:49, 22 September 2006 (UTC)

One suggestion: Perhaps it has a "fake head" on it's tail, making it appear to be hopping backwards. If you capture one, look closely at the end that appears to be the tail, and see if there is a less obvious head at that end. StuRat 03:26, 22 September 2006 (UTC)

Your description reminded me of the cave crickets (aka camel crickets) who shared our basement flat in Virginia. I remember them hopping in all directions and usually when I least expected it. Here's a google image search, is this your bug? ---Sluzzelin 06:52, 22 September 2006 (UTC)

Milk --> cheese?

What happens to milk after you drink it? does it turn into cheese?--Light current 23:41, 21 September 2006 (UTC)

A protein called rennet solidifies the milk, and you can then digest it as if it is a food. Juveniles have much more rennet than adult mammals. So, in a way, yes it does turn into cheese, as it was this protein (and may still be, can't remember) which probably caused the first cheese to be made, and had been used for centuries after. People used to get cow or sheep stomach lining, and, as it contained rennet, would use it solidify milk into cheese before it was ingested. --liquidGhoul 00:11, 22 September 2006 (UTC)

Some cheeses are still made with animal rennet. Rmhermen 01:48, 22 September 2006 (UTC)