Wikipedia:Reference desk/Archives/Science/2006 July 22

cancer development
In cancer development, what controls the cells normally???
 * The cells in a living organism are finely balanced between proliferation (dividing) and programmed cell death (dying). There are many proteins involved in regulating these processes. Our articles on carcinogenesis and the cell cycle should explain in more detail, but for example, there are tumor suppressor genes such as p53, that encode proteins that, when functioning correctly, regulate the cell cycle and make sure uncontrolled division does not occur.  Rockpock e  t  05:34, 22 July 2006 (UTC)

information technology
what is informtion technology? what all topics are included in it? give notes ..
 * Information technology. Melchoir 07:28, 22 July 2006 (UTC)
 * Studying the use and how computers work, and how they are used in businesses etc. Iola k ana |T  11:35, 22 July 2006 (UTC)
 * Information technology is one means by which students attempt to have others do their homework for them. --Ginkgo100 talk · contribs · e@ 17:40, 23 July 2006 (UTC)


 * Everybody else forgot to give notes, so here are a few .... C-sharp. A.  D-flat.  F.  --LarryMac 13:12, 24 July 2006 (UTC)

Evolution
Why don't humans have gills? Or wings? Clearly both would offer a fitness advantage. (And before anyone says "Humans have gills during embryonic development", they don't. They have things that look like gill pouches, but these develop into parts of the face, ears, and endocrine glands.) BenC7 09:20, 22 July 2006 (UTC)


 * Gills would be nice, but it would probably require a lot of energy to maintain both gills and lungs. Apparently it was too expensive to have both, so we lost the gills.
 * Wings would be pretty useless unless we could fly. In order to fly we'd have to have a lot more than just wings; the entire body would need to undergo some extreme changes. These changes might make us less fit to do things like climb trees, lift weights, run fast, and so forth; in our course of evolution it was more important for us to be able to do these things than for us to be able to fly. —Bkell (talk) 09:39, 22 July 2006 (UTC)


 * Also keep in mind that humans are not the end goal of evolution; that's anthrocentric thinking. We're just one step in the evolutionary chain. Maybe millions of years from now humans will have evolved into something that has gills and wings, if those things turn out to be important. —Bkell (talk) 09:43, 22 July 2006 (UTC)


 * The chain analogy really doesn't belong in a discussion of evolution either. It's part of the theocratic paradigm that evolution replaced, the Great Chain of Being. Evolution isn't directed towards a goal, and species might best be conceptualized as a web, rather than a ladder. - 09:48, 22 July 2006 (UTC)


 * Good point. I should have worded that better. —Bkell (talk) 10:11, 22 July 2006 (UTC)


 * Well the basic reason I see that we don't have gills or wings is because we managed to become the dominant species on the planet without them, so it would just be a waste of energy to have them. Philc  TECI 17:28, 22 July 2006 (UTC)


 * Speaking of anthrocentric thinking, what makes you think we are the dominant species on this planet? DirkvdM 18:50, 22 July 2006 (UTC)
 * I see us as the dominant species on the planet because we have the ability to claim such a title, and defeat any challengers. Philc  TECI 20:03, 22 July 2006 (UTC)


 * Have we defeated the mosquito yet? And what about that shitload of diseases we can't beat? DirkvdM 06:13, 23 July 2006 (UTC)


 * Have they defeated us, and claimed the title? We are in a better postion than them because, given the choice we can just pull the plug and everyone loses. Philc  TECI 15:55, 23 July 2006 (UTC)


 * No we can't. We certainly can't eliminate all life on Earth, but we can't eliminate mosquitoes and diseases either. But that's hardly a criterium. We coexist and have to live with it. Neither can claim the title of dominant species. Of course we can focus on things we find important, but then we'd be defining 'dominant' by our own criteria, and that would be cheating. That said, what criteria would that be? Algae beat us by biomass. And most animals are faster. Of course we've got technology to make us go faster. And we may be the only species to have gone in to space (is that certain, though?). But, like I said, then we'd be defining the measuring stick, which is cheating. So we've been to space. Who cares? Only we do. DirkvdM 18:01, 23 July 2006 (UTC)


 * We can eliminate all life on earth. Just nuke the whole thing, and to make it certain, do it in such a way that the planets orbit is disrupted and slowly spirals into the sun. You going to claim mosquitos will survive that? Philc  TECI 21:39, 23 July 2006 (UTC)


 * No, I just claim that we couldn't. We couldn't knock Earth out of its orbit (that was a question here a few days ago). And even if we could directly kill most life on Earth with nukes (which I doubt), we certainly couldn't kill all life. Loads of bacteria would survive. What, bacteria don't count? Says who? Us? That's my point.
 * And anyway, like I said, that's hardly a criterium. Now if we could do that without hurting ourselves, that might be a different thing. But we couldn't do that either. What would we eat, for one? No more plants on Earth would eventually kill us too. And what kind of a criterium is destructiveness anyway? What about the ability o co-exist? DirkvdM 08:54, 24 July 2006 (UTC)


 * Well no other species can simaltaneously cause as much damage to toher species, whilst not endangering the long term existence bof their own as ours. Philc  TECI 13:39, 25 July 2006 (UTC)


 * The ability to damage other species just isn't a criterium. A better one would be the ability to alter the environment such that you can live anywhere (even potentially on other planets one day). But then that is again a human criterium and of course if we get to determine the criteria we allways win. But even here, there's a problem. We are probably altering our environment in such a destructive way (your criterium) that we might be making it less inhabitable for ourselves. So we lose by our own criterium. How unsuccessfull is that? DirkvdM 08:54, 26 July 2006 (UTC)


 * It is true to say that maybe we cannot prove we are the dominant species, but I think that we are, and I think that a mojority of civilised life forms in the universe would agree that we are, on our planet the dominant species, seeing as dominant comes from the latin for master, and we can be the masters of most creatures. But anyway, I don't think humans could ever eliminate themselves completely, because the intelligence of few outwieghs the stupidity of masses. So even if a colossal amount of people made huge mistakes and destroyed the planet somehow, I think that there would be survivors on some craft tasked with setting up a new civilisation. Philc  TECI 14:25, 26 July 2006 (UTC)


 * A change from destruction to being master. Quite an improvement. But don't assume what aliens would say coincides with what you think and then use that as an argument. That is circular reasoning. Also, there are loads of other species that use other species for their benefit (symbiosis, epiphytes, vines). We, however, do this to more species at the same time. In general, we are more versatile and that really sets us apart from other animals. At least, by our standards. There's that counter-argument again. I think I am dominant, therefore I am. DirkvdM 09:15, 27 July 2006 (UTC)


 * FYI, the singular form of the plural criteria is criterion, not criterium. (From Greek, not Latin.) Chuck 20:54, 27 July 2006 (UTC)


 * We don't have gills or wings because we evolved from species that also didn't have gills or wings. They, like us, didn't have them because they were long longer advantageous for survival and reproduction in the ecological niche in which they live.
 * I don't see the clear "fitness advantage" wings, for example, would offer us. It is generally considered that the use of tools (to make fire and hunt) was a key step in Homo evolution, replacing our arms and hands with wings would have put paid to the pretty quickly. Same goes for gills. How many animal with gills do you know that can talk?  Rockpock e  t  19:25, 22 July 2006 (UTC)


 * I don't know of any animals that can talk... BenC7 03:59, 23 July 2006 (UTC)


 * Talk is communication. Loads of animals communicate through sound, so they talk. Don't know about fish, though. DirkvdM 06:13, 23 July 2006 (UTC)


 * There are several reasons, but perhaps the most obvious one is that these structures would be quite useless in humans, as Bkell mentions above. Possessing wings does not imply possessing flight, and even if our bodies were radically modified to permit some sort of flight, it would be very difficult to maintain sufficient energy for both flight and to supply our brains. Not to mention that wings in vertebrates are modified from the forelimbs; in the bat, the finger bones (phalanges) are stretched out to make the scaffolding of the wing. Gills are even less useful. Breathing underwater is not the issue; there's not enough oxygen dissolved in water to meet the needs of humans, especially of our energy-demanding brains. Note that dolphins and whales must return to the surface to breath air to support their mammalian physiology (warm-blooded) and their intelligent brains. — Knowledge Seeker দ 19:34, 22 July 2006 (UTC)


 * Yeah, wings won't let humans fly. On the other hand, shouldn't sufficiently large, superfluous structures on our shoulder blades make us unstoppable in battle? Melchoir 20:06, 22 July 2006 (UTC)


 * I think the discussion of what makes wings useful or not useful is beyond the point, and assumes we are ideally evolved (we're not). We have the limbs we do because we are evolved from big-brained apes, and the reason they are the way they are is because that is what ended up being most adaptive in their environments, etc. etc. If dolphins had found a way to use tools and had a major incentive to develop culture-bearing brains we'd probably be typing out these questions very carefully with our noses underwater. --Fastfission 00:12, 23 July 2006 (UTC)


 * A common error people make is to think evolution should come up with the best possible solution to the problems of survival, whereas it actually comes up with whatever works -- if an adaptation gets the individuals of a species to breeding age, then evolution's happy -- it doesn't care whether you're happy, just as long as the selfish genes are allowed to propagate themselves Adambrowne666 07:15, 23 July 2006 (UTC)


 * Ben, you wrote "Why don't humans have gills? Or wings? Clearly both would offer a fitness advantage." As Bkell noted, you are forgetting that maintaining gills or wings comes with costs, and for organisms in the hominid niche, the overall effect of gills/wings in adult hominids would very likely be to decrease fitness, however useful this might seem for a Rambo or a James Bond :-/  Here's a classic book on adaptation which discusses this point:
 * Enjoy! ---CH 02:50, 24 July 2006 (UTC)
 * Enjoy! ---CH 02:50, 24 July 2006 (UTC)


 * I would like to add an opinion to the "greatest species" debate. Although we pose certain dangers to ourselves (say, nuclear war), and although some disease might suddenly develop that can wipe us out (less likely than it sounds), those are the only major dangers to the species, barring forces of nature. We have conquered and, in many cases, annihilated, every other major predator in our environment. Name a predator we couldn't make extinct in a month. Although food shortages are a big problem in certain areas of the world, species-wise, we're very good at finding or even producing as much food as we need. You can nitpick if you want, but we really are at the top of the food chain. Based on the evolutionary definition of fitness, as well as the commonsense one, we really are pretty awesome. We can outcompete everything that even vaguely resembles us. Bacteria are a little more difficult, but we're getting there. Viruses, being nonliving, obviously don't count. Black Carrot 13:28, 24 July 2006 (UTC)


 * Feel the sides of your neck. You will feel ridges on your neck. These are your "gill slits." Bibliomaniac15 00:29, 26 July 2006 (UTC)
 * You're insane. --mboverload @ 00:36, 26 July 2006 (UTC)

The actual answer, mostly found in bits and pieces above, is simply that the ancestors of homo sapiens lacked these structures. In fact, the loss of gills is part of the radiation of reptiles from an amphibian common ancestor. Mammals and birds were separate radiations from reptilian common ancestors, and bats a radiation from a mammalian common ancestor. (Bat wings and bird wings are examples of convergent evolution.)

Another problem in the posed question (also sporadically addressed above) is that gills and wings wouldn't necessarily provide a selective advantage. It would take more than simple genetic variation to produce functional wings or gills in a human. The step-wise selection of progressively more functional and specilized features (underlying evolution by natural selction) hasn't had any known success in producing gills since the feature was lost in the evolution of reptilian ancestors. Wings and gliding apparatuses, on the other hand, have popped up in many separate lineages. For the ancestors of bats, gliding among tree branches using primitive wing-like webbings between their fingers may have been a selective advantage that progressed into more functional wings. I can't think of any obvious small phenotypic step in the paths towards fully functional wings or gills that would be selected for in human environments today...Maybe Waterworld has the answer? -- Scientizzle 20:34, 28 July 2006 (UTC)

Hypoglycemia in diabetics
I've understood that hypoglycemia can sometimes be a problem in the morning for some diabetics, due to the prolonged time without food. Why is this? In "normal" persons gluconeogenesis will provide the glucose during sleep, doesn't it in diabetics? If so, why not?

Also, in hypoglycemia caused by too much insulin (and let's assume mild yet noticeable hypoglycemia in this instance), how effective is the insulin in inhibiting the effects of catabolic hormones (which I assume are released in diabetics also in hypoglycemia)? Glucagon, cortisol and epinephrine will be released; is insulin able to inhibit their effects entirely? Jack Daw 10:29, 22 July 2006 (UTC)


 * second question first: yes, it's a matter of dosage. Insulin in pharmacological doses can overcome all the counterregulatory hormones in physiological dosages. The hypoglycemia at night is due to medication taken before bedtime that (unlike natural insulin) will not be "down-regulated" when the blood sugar is low because of fasting during sleep. You might also be interested in the Somogyi effect (what? no article?) in which hypoglycemia during the night results in an increase in counterregulatory hormones, resulting in an elevated blood glucose reading in the morning (despite hypoglycemia at night). The seemingly logical, but wrong, response to an elevated morning glucose level might be to increase insulin dosage, whereas what is needed is actually a decrease. So there's a complex interplay between the duration of action of hypoglycemic agents and time and size of the latest meal that makes results difficult to predict - thus the need for vigilant monitoring. -- Nunh-huh 10:53, 22 July 2006 (UTC)


 * Why is insulin taken before bedtime? That sounds very strange, what's the rationale for that? After your last meal of the day, which presumably is a few hours before bedtime, you'd take some insulin and let glycogenolysis and gluconeogenesis take care of the rest...? Jack Daw 10:50, 23 July 2006 (UTC)

See the diabetic hypoglycemia article. Insulin can be taken before bedtime for several reasons: to cover food eaten at bedtime, to correct a high glucose found at bedtime, or to provide basal insulin through the night. alteripse 14:15, 23 July 2006 (UTC)
 * I understand the first reason you stated, not the others though. Regarding the second reason, isn't it possible to go to bed with hyperglycemia and wake up with normoglycemia? I mean, since the brain and so on will need glucose during the night. Also, if one has hyperglycemia at bedtime, why not just take some fast-acting insulin rather than insulin that will block hyperglycemic agents the entire night? Reagrding the third reason, I only ask Why? Why is that necessary? Is this because once hyperglycemia is triggered by hyperglycemic agents, it can't be suppressed in absence of insulin (leading to DKA...)? Jack Daw 14:57, 23 July 2006 (UTC)
 * One can go to bed with hyperglycemia and wake up with hypoglycemia if (1) one still has enough beta cell function to produce some insulin or (2) one has taken/is getting long-acting insulin through the night in excess of basal needs to bring the glucose down to normal or (3) one has done something (e.g., prolonged exercise earlier in the day) to enhance one's sensitivity to the usual amount of overnight insulin. I do not understand your second question-- taking fast acting insulin is exactly what I was referring to: the phrase "insulin that will block hyerglycemic agents the entire night" is meaningless to me. Your third question seems to be "why do we need basal insulin through the night?". Because if the insulin level declines below one's basal requirement, starvation metabolism (i.e., ketogenesis) and excessive hepatic glucose output are activated. An entirely insulin-deficient persoon (a typical person with type 1 diabetes needs some basal insulin. I do not know what you mean by "hyperglycemic agents". Dividing a type 1 diabetic person's insulin needs into basal, food coverage, and hypergycemia correction is explained better in the poorly-named intensive insulinotherapy article. alteripse 15:17, 23 July 2006 (UTC)


 * "One can go to bed with hyperglycemia and wake up with hypoglycemia if..."; not hypoglycemia, normoglycemia. For example, if a diabetic goes to bed with only slightly elevated blood glucose, say 7mmol/l, surely the brain uses enough glucose during 8 hours of sleep to get that below 6.1mmol/l? I'm just guessing though. As for my second question, if you meant fast-acting insulin, I'm wondering how fast-acting insulin can provide basal insulin for the 8 hours or more that people sleep? I thought fast-acting insulin waned shortly after injection? And yes, you understood my third question correctly. Question, then, couldn't it be OK to let ketogenesis have its way during sleep (which is a short time after all) and then correct it in the morning, instead of providing basal insulin at night and risk hypoglycemia in the morning? (Btw, by hyperglycemic agents I mean glucagon, cortisol, epinephrine) Jack Daw 19:16, 23 July 2006 (UTC)


 * After I wrote I realized I had intended to write normoglycemia rather than hypolycemia but there was no difference except a mmol/l or two. All statements apply to both. I think you might be speculating from a fairly simple model of metabolism. The brain of an adult uses about 4-6 mg/kg/min of glucose. However, what is more important is the rate of glucose production from the liver throughout the night. Basal insulin in the right amount (made by your pancreas or taken by injection or pump by a diabetic person) normalizes the hepatic glucose production, but too much lowers the glucose too far. The therapeutic goal is simply to maintain a steady glucose with basal insulin. As far as your second question about fast acting insulin goes, I did not say that fast acting provides basal because it doesnt. Fast acting would be taken to cover food or bring a high glucose down to normal, but fast acting insulin can only serve as basal insulin when steadily infused from a pump rather than an injection. A few hours of ketogenesis is relatively harmless in healthy people, but if it occurs every night will interfere with growth hormone production and other anabolic processes, especially in children. In someone with type 1 diabetes, the problem with supplying so little overnight insulin that ketogenesis occurs is that it can quickly evolve to diabetic ketoacidosis and would be accompanied by several hours of marked hyperglycemia, which is damaging to blood vessels and contributes to long-term complications. Finally, if you want a common collective medical term for glucagon, cortisol, epinephrine and growth hormone, it is counterregulatory hormone. The term counterregulatory is a poor one but long-used-- "counter-insulin" might be better but I just coined it. Now I understand what you mean, but the similarity to "hypoglycemic agents", a synonym for diabetes drugs, made me wonder if you meant exogenous agents. Have I covered everything? alteripse 19:44, 23 July 2006 (UTC)


 * Yeah I think so :D Thanks Jack Daw 17:06, 26 July 2006 (UTC)

What data to use for an experiment?
I have done a small experiment for a project. I tested people's short term memory by getting the subjects to view some cards with letters on them then see how many they can recall. I am trying to see if and by how much age effects memory.

I had 7 cards with increasing number of letters to remember on them, for example here is the data from one person I surveyed:

Q1 2/2 100%

Q2 4/4 100%

Q3: 6/6 100%

Q4: 7/8 87.5%

Q5: 7/10 70%

Q6: 8/15 53.3%

Q7: 11/20 55%

I have used two ways to put together this data, one is averaging all the percentage scores, eg: 100 + 100 + 100 + 87.5 + 70 + 53.3 + 55 / 7 = 80.83% average, the other is just adding them up and marking it out of 65 which is 45 for this particular subject giving me 45/65 = 69.2%

Which is the more accurate way of putting this data together on a scatter graph to try to conclude if age effects memory? the averaging of the percentage scores or the adding together of the scores and marking it out of 65 (there are 65 questions)?


 * You should really be drawing curves, averaged for each age group (I assume you have more than one subject in each age group, otherwise you need more data in the first place). Log of number of letters presented goes on the x, percentage on the y. You'll have to see what sort of curve fits best, it'll probably be sigmoidal in shape. - User:Samsara (talk • contribs) 11:51, 22 July 2006 (UTC)

I have about 10 in each age group, cheers, ill check that out.


 * You could use one of those weird graphs that have a box where the mean average is and then lines up and down to points where the min/max values are for each age. I'm not a stat person, so I don't know the proper name for that sort of graph.  On the Y axis you have the percentage.  On the X you have age groups.  Then, for each age group, you will be able to see the averages easily as well as the deviation from the average. --Kainaw (talk) 14:18, 22 July 2006 (UTC)


 * I suspect you're looking for a scatter plot where the points are the means and the error bars are equal to the standard deviation? To convey more information, one can also use a box plot, although I'm not sure if your sample is large enough for one to be meaningful; if you're overlaying curves from the different age groups you'd also have too much visual clutter.


 * Depends on what you want to measure, but the most important thing is that you make it clear how you came to that percentage (ie, which of the methods you used). I so often encounter percentages that are very suggestive but lack that sort of info, thus making them useless. Still, people read all sorts of things in them, which makes it dangerous misinformation. There should be a law against that (and I mean that literally).
 * Anyway, the first method seems to make most sense. You don't want to know the overall score but how they perform on average per test. The second method puts more emphasis on the tests with the greater number of letters. You might want that, but this is a random method of achieving that. If you want to do that think about why and the answer to that will probably tell you how you would have to distribute the weight between the tests and then adjust according to that (in stead of the number of letters).
 * That said, do you really want an average per person? As I understand it you're not testing individuals but age groups. So don't you want averages per test and per age group? You then have three variables, age, test and score. So you'd have to make several graphs (unless you can do it three dimensionally), one for each age or one for each test. DirkvdM 19:09, 22 July 2006 (UTC)

Torn ligament
For a torn ligament in the left ankle, which would generally be a more effective treatment: Chinese or Western medicine, and why? --J.L.W.S. The Special One 15:59, 22 July 2006 (UTC)


 * It depends on what you believe. If you believe in the Qi, for which there are substantial testemony, the chinese medicine and treatment. However if you solely believe in what has been proven, which is possibly both the safer and more dangerous choice, because though we think we understand the body, our knowledge is not complete. Whereas the chinese option is perfected through thousands of years, though not understood. Philc  TECI 17:41, 22 July 2006 (UTC)


 * Actually I think it's the other way around. I think traditional medicinal traditions tend to take the attitude that they completely understand the body - they usually have an all-encompassing philosophy that supposedly explains everything.  On the other hand, no respectable doctor or medical researcher would ever claim that they really "understand" the body.  That's why there are still medical scientists - many aspects of the body are still mysteries!   --18.239.6.57 18:15, 22 July 2006 (UTC)


 * Rest. Be it Chinese or western. :) DirkvdM 19:14, 22 July 2006 (UTC)


 * I'd follow non-invasive Western treatments like ice and NSAIDs, but if it doesn't heal quickly I recommend Acupuncture. I've personally had stellar results with acupuncture and sports-related injuries (Plantar fasciitis, torn tendons and ligaments, etc), although a good practitioner is key. Personally, if surgery is the option, I'd exhaust everything else first.--Anchoress 23:24, 22 July 2006 (UTC)

Personally I think "Chinese Medicine" is an oxymoron. Use your common sense, and visit a doctor. --Kjoonlee 15:40, 23 July 2006 (UTC)


 * (I think you are misusing the word "oxymoron" - if you really meant "oxymoron", you would be implying that Chinese people are incapable of medicine.) —AySz88\ ^ - ^ 03:00, 24 July 2006 (UTC)

Interspecies Fight Club
If a bear and a gorilla had a fight, who would win? Vitriol 22:48, 22 July 2006 (UTC)


 * bear...definitely bear.


 * Gorillas have been known to use tools, so it depends on that aswell. If the gorilla sat about 10 metres away chucking huge rocks at it, and running away if the bear came closer, then the gorilla probably. Philc  TECI 23:15, 22 July 2006 (UTC)
 * I don't think tools would make much of a difference, unless the tool was an AK-47 or a key to the door of an animal refuge. Of course the gorilla could get away from a bear, but the rules of the interspecies fight club are more 'Ring of Death' than 'accidental encounter'.--Anchoress 23:30, 22 July 2006 (UTC)
 * I already explained the usefullness of rocks as tools in this encounter. Philc  TECI 15:52, 23 July 2006 (UTC)
 * Depends on which is a figment of the other's imagination. Unless one of them has wings. Melchoir 23:43, 22 July 2006 (UTC)

Trouble is, I can't see many animals winning against a bear. Vitriol 00:43, 23 July 2006 (UTC)
 * I've read that among predators weight is the primary deciding factor in a fight; the bigger animal will likely win. I don't endorse that opinion, I'm just repeating it, lol, but taking that into consideration, the big cats would probably have a good chance against a black bear or a small brown bear. I think tigers are 5-700 lbs? But the Polar bear is considered the pinnacle land predator, and it ranges from 1200-2000 lbs.--Anchoress 00:57, 23 July 2006 (UTC)


 * I'd imagine that an elephant, rhino, or hippopotamus could quite easily defeat a bear if in the mood for a fight, albeit taking some damage in the process. --Kurt Shaped Box 01:09, 23 July 2006 (UTC)


 * Also, a giraffe could kill a bear with one well-placed kick, if enraged/cornered enough to fight. --Kurt Shaped Box 01:12, 23 July 2006 (UTC)


 * Depends on the bear. If it's a Giant Panda, neither would be bothered. In case you're thinking about a Grizzly bear, it would also have to have a reason to attack. But if it would wish to rip the gorilla to threads, it could. But to expand on the wings-comment, both would probably go "What the fuck....". DirkvdM 06:27, 23 July 2006 (UTC)


 * Hmmm... If you really, really, really riled a koala bear, it might erm give the gorilla a really mean look. --Dweller 11:07, 24 July 2006 (UTC)


 * My brother told an awesome story about a real-life incident along these lines. Some of his friends were hiking in the woods with a mule, and came across a mountain lion. And the mule kicked its ass. Seriously, those hooves are dangerous. Apparently it started by sideswiping the cat's head with one of its front hooves, then just started stomping on it. True story. First rule of interspecies fight club? Don't mess with mules. Black Carrot 13:00, 24 July 2006 (UTC)

the mule-cougar tale is a hoax: http://www.snopes.com/photos/animals/mulelion.asp

Check out Animal Face-Off (and this online game). Fredrik Johansson 13:14, 24 July 2006 (UTC)


 * So size matters after all. At least, that seems to be the determining factor in these outcomes. The walrus beating the polar bear surprised me until I looked them up. A polar bear weights 400 - 800 kg, but a pacific walrus weighs up to 1800 kg. That's 3 times the weight of the bear. DirkvdM 05:57, 25 July 2006 (UTC)


 * Drop a bear into the ocean and an Orca would make short work of it :) &mdash; QuantumEleven 08:02, 25 July 2006 (UTC)
 * LOL the bear wouldn't even need to be in the ocean. I've seen video of an orca snatching a polar bear right off an ice floe.--Anchoress 08:12, 25 July 2006 (UTC)

Re the general discussion, I nominate the wolverine, which has been known to hunt grizzlies (and humans) for sport. But about the polar bear vs orca thing - which I've seen the same video, or another like it, as well as orcas pluck seals and sea lions off their rookeries - another critter that is aquatic and terrene, though much better in the water, is the unseemly but violent and deadly hippopotamus. Can't remember where I saw the mention, but apparently they can be encountered hundreds of miles out in the Atlantic, happily swimming away and hunting....there aren't Orcas in the South Atlantic (not that I know of) but a big juicy hipppo that's that far offshore (and apparently knows the way home) must be tasty temptation for a shark; but something about the hippo suggests to me it would win that fight....and the comments about giraffes vs. bears are apt; a bull moose can defend itself quite well with kicks, as can a cow if she doesn't have a calf to worry about; anyone ever see that newstape of the guy walking out of the bank in Anchorage and getting his head kicked off by a startled moose, which had wandered into the city's downtown?Skookum1 08:37, 25 July 2006 (UTC)
 * Yeah, hippos really are deadly.--Anchoress 08:57, 25 July 2006 (UTC)
 * I wonder what these hippos in the Atlantic are hunting? Land, or seaweed? While Hippopotamus agrees "They are said to account for more human deaths than any other African mammal" it does also say that they are "plant-eating". Notinasnaid 09:46, 25 July 2006 (UTC)


 * Of course, the size rule doesn't always apply - put the meanest grizzly up against certain viruses, and my money's on the virus Adambrowne666 07:15, 26 July 2006 (UTC)


 * Or a human with a big enough gun (would have to be pretty big to not just piss the grizzly off). Few rules are truly universal. DirkvdM 08:58, 26 July 2006 (UTC)


 * That'd be a good one - wannabe gangsta tough guy from the 'hood with Desert Eagle .50 vs. grizzly bear... ;) btw, anyone know where I can find the aforementioned videos? --Kurt Shaped Box 13:32, 26 July 2006 (UTC)


 * Any gangster worth his salt would have that grizzly in a body bag within minutes. Don't be silly. Way better: let's give him a shiv and see how he does. Black Carrot 05:31, 27 July 2006 (UTC)

Takeout containers for frozen food storage - any concerns?
I'm thinking of using metal takeout containers from restaurants to store food (like soups etc) in the freezer. I have a lot of them, and I find my plastic tupperwear-type containers don't fare well in the freezer, even tho they're supposed to be freezer-safe. My question is, are there any chemical reactions that might happen long-term that I should worry about?--Anchoress 23:28, 22 July 2006 (UTC)


 * Very acidic food (things with a lot of vinegar or lemon juice) can oxidize metal, so if the container is made of a toxic metal like copper, or aluminum (may cause Alzheimer's), there might be a remote possibility of harm. I wouldn't worry about it, though, because the amounts are so tiny. You probably get more aluminum from drinking acidic cola out of aluminum cans. Plus, the low temperature in the freezer will tend to slow down chemical reactions. —Keenan Pepper 04:13, 23 July 2006 (UTC)
 * Thanks KP, that's kind of what I was thinking. I thought, Oh no, alzheimers, but then I thought about aluminum pop cans that sit for months in the sun.--Anchoress 06:09, 23 July 2006 (UTC)
 * Aluminium cans are varnished inside ("How food and drink cans are made" - see Section 5). Takeaway trays are probably not. --Heron 10:02, 23 July 2006 (UTC)
 * Well, you probably get more aluminum from drinking tap water anyway. —Keenan Pepper 18:45, 23 July 2006 (UTC)
 * Although aluminum is associated with Alzheimer's patients, there is no empirical evidence that environmental exposure to aluminum is a risk factor for the disease. See this link. I think you can relax. --Ginkgo100 talk · contribs · e@ 17:48, 23 July 2006 (UTC)