Wikipedia:Reference desk/Archives/Science/2009 September 8

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September 8

Animals fighting...

What's the technical term for a fight between two animals where neither combatant is fighting to its full capability in order to ensure that neither is killed or permanently maimed (with the rationale that 'if I go all out on him, he'll go all out on me and we'll kill each other')?

I've been watching gull videos on YouTube again tonight and I've discovered more examples of the previously-discussed 'tug-o-war beak wrestling' - e.g. here and here and I had a moment of realization that that purpose of these conflicts may actually be to ensure that neither bird can attack with its beak (because, let's face it - two gulls could rip each other up pretty badly if they really went at it), whilst both attempt to overpower the other and get him into a position where he can be 'submitted' and forced to disengage and fly away - all with minimal bloodshed. Kind of like a gull version of our submission wrestling, where the object is to get the other guy to tap out, rather than put him into intensive care. I don't know if this is obvious to anyone else - but it never really clicked with me until now...

I've looked for a WP article discussing this behaviour (in animals in general - not just gulls) but all I've found is references to human combat. Any ideas, guys? --Kurt Shaped Box (talk) 01:55, 8 September 2009 (UTC)

The term that occurs to me is "ritual combat", and I'm pretty sure that's what ethologists call it, however our ritual combat is a redirect to an article that doesn't mention animals. Looie496 (talk) 02:28, 8 September 2009 (UTC)

Well, it's probably a form of intrasexual selection, though that isn't the name of the combat itself. It's of note that almost all intraspecies fighting is of the nature you describe—it is rarely meant to be fatal, and instead is about posturing, submission, etc. (Interspecies is a totally different question.) There is a lot of discussion of this in On Killing (specifically, that there are other options than "fight" and "flight"—"posturing" and "submission"). --98.217.14.211 (talk) 02:50, 8 September 2009 (UTC)

Perhaps relevant aphorism: I read once that -- due to the large difference in how serious their weaponry is -- when fighting for mates, "doves are hawks and hawks are doves". --Sean 16:22, 8 September 2009 (UTC)

Funnily enough, I saw a video on YouTube of two hawks fighting last year - it was less violent than in the gulls. One hawk had the other one pinned on its back and proceeded to gently 'beak tap' it until it gave up. I suppose the perception that "I've got you at my mercy and I am now in the position to deliver a fatal blow if I so wished" is enough to bring the fight to an end. It looks to me as though that's what happened in the second gull video - when one bird had the other by the neck/throat. --Kurt Shaped Box (talk) 20:17, 8 September 2009 (UTC)

Based on the animal videos I've seen, the same thing goes for wolves, lions, and other large predators. So yeah, I suppose that's because they're more likely to kill one another during ritual combat than other animals. Funny thing, though, in Jack London's Call of the Wild, dogs and wolves do fight one another to the death (and I mean dogs vs. dogs or wolves vs. wolves, not wolves vs. dogs). That's a pretty odd thing, considering that he actually did spend a long time in the far north and prob'ly witnessed enough dog-fights to become an expert on the subject. 98.234.126.251 (talk) 05:59, 9 September 2009 (UTC)

Are we talking about dog fighting, or fights between dogs here? The dogs in the former have a somewhat different mindset. --Kurt Shaped Box (talk) 14:45, 9 September 2009 (UTC)

In this case, we're talking about spontaneous fights between dogs (mostly over food, but sometimes over other things too). 98.234.126.251 (talk) 02:38, 10 September 2009 (UTC)

I think Dawkins mentioned this in The Selfish Gene, though I can't find a definite attribution. IIRC, his example was in rattlesnakes, who rarely, if ever, strike one another when fighting over a mate. A single bite would almost certainly be deadly, yet both combatants refrain and therefore increase their risk of losing, but increase their odds of living. In a way, this is a kind of invisible Green-beard effect. That's part of the gene-centered view of evolution, though, so other theorists will have different explanations. Matt Deres (talk) 16:37, 8 September 2009 (UTC)

Animals need to have occasional confrontations to maintain their Dominance hierarchy or pecking order which will reduce the incidence of intense conflicts that incur a greater expenditure of energy. Cuddlyable3 (talk) 13:13, 10 September 2009 (UTC)

Just like us people, we gotta pick fights every once in a while to blow off steam, else we might explode. (BTW, the same mechanism might be operating on an international scale as well -- and in that case, efforts to achieve "world peace" would actually do more harm than good.) 146.74.230.106 (talk) 21:36, 10 September 2009 (UTC)^{[citation needed]}. Fences&Windows 00:16, 13 September 2009 (UTC)

Space shuttle landing stuff

In the article, Space Shuttle Columbia disaster, in the section "Destruction during re-entry," it gives a sort of play by play of the events of the landing up to and including the disintegration of the orbiter. Like this:

* 8:53:26 (EI+557) – Columbia crossed the California coast west of Sacramento. Speed: Mach 23; altitude: 231,600 feet (70.6 km; 43.86 mi).

Anyway, is there anything similar out there for one of the sucessful landings? I've looked but I can't find anything. I'm really amazed that the Columbia made it across California in a minute and a half, and I got so into looking at the data that I nearly forgot that this mission was going to end in disaster. It seems that this list was made for some commission looking into the accident, so maybe no one has made anything for one of the many times that things went right.

Thanks for your time. I always appreciate the effort that goes into anwering these questions.

169.231.32.17 (talk) 05:29, 8 September 2009 (UTC)

The mission log websites that I've found don't really have the detailed point by point logs like you seem to be after. http://science.ksc.nasa.gov/shuttle/missions/ http://www.nasa.gov/centers/kennedy/shuttleoperations/archives/2005.html It's just about unbelievable that the shuttle has to decelerate from 17500 mph, nearly 30 THOUSAND kilometers an hour. . Vespine (talk) 06:43, 8 September 2009 (UTC)

The ill-fated mission didn't result in the shuttle re-entering any faster or slower than it should have done - so the timeline for a successful mission would be pretty similar. However, they don't always come in on the exact same track - so there would be differences of location - if not of speed. http://spaceflight.nasa.gov/realdata/sightings/ offers data for an upcoming landing - in order that amateur 'shuttle-spotters' will know when and where to look. I don't think that's precisely what you want but the interactive applet has a gazillion options for finding out where pretty much any NASA vehicle is at any time - or when it will cross a particular state. That MAY enable you to figure out what you want to know. SteveBaker (talk) 10:58, 8 September 2009 (UTC)

The NASA TV Public Affairs commentary also gives intermittent speed and altitude callouts as the orbiter descends. Arakunem^Talk 20:22, 8 September 2009 (UTC)

You may want to login into the NASA system and ask them that question directly: See 42. You may have to wait for 2 weeks to get an answer, but you should get reliable information. Michel M Verstraete (talk) 19:19, 9 September 2009 (UTC).

The NASA TV channel worked for me last night - at 8:11pm central time the shuttle and space station zipped across the Texas skies right on cue. The sun had only just set and the sky was still pretty bright - yet they were easily the brightest objects in the sky - crossing from horizon to horizon in just a few minutes. The shuttle was about a hand's-breadth in front of the space station and you could easily tell them apart with the naked eye. With binoculars, you can see the big solar panels and really get a feel for just how gigantic the ISS has become. Very impressive...also a complete waste of money - but that's another story! SteveBaker (talk) 13:43, 9 September 2009 (UTC)

Thanks for all the responses. I have gotten ever closer to the info I want, and if I put it together I should have something interesting. Maybe I should share it? —Preceding unsigned comment added by 169.231.32.17 (talk) 08:59, 10 September 2009 (UTC)

Yes, absolutely. --Tagishsimon (talk) 09:13, 10 September 2009 (UTC)

Quickly drying a heat-sensitive powder

Hello. I am wondering if anyone can direct me to a manufacturer of equipment for quickly drying a powder that is highly heat sensitive. The powder must remain below 30 C. Our current method is; after reprecipitating the product using water to dissolve and acetone to crash out for purification, we air dry in a humidity-reduced room, then dry under vacuum in pans until the product is a consistent weight. Some method of drying the product more quickly without heating it is necessary. A small amount of water hydration will remain, but the excess moisture needs to be removed. Thank you in advance for your help. 134.217.112.15 (talk) 15:49, 8 September 2009 (UTC)

Agitate the pans, and heat them to 30 C (or whatever safe temperature is below the decomposition temperature of your product). The evaporation of water from the material will tend to chill the remaining material, reducing the rate of further evaporation (even under vacuum). Agitation ensures that water remains uniformly distributed over the exposed surface (maximizing evaporation), and will encourage the breakup of water-retaining clumps. Sifting through screens or shaking in the presence of inert metallic or ceramic balls will have a similar effect. TenOfAllTrades(talk) 22:32, 8 September 2009 (UTC)

Why not do a vacuum filtration? Is the powder water-soluble? John Riemann Soong (talk) 22:44, 8 September 2009 (UTC)

I know absolutely nothing about lab techniques, but what about Freeze drying? -Arch dude (talk) 01:08, 9 September 2009 (UTC)

You could put it in a round-bottom flask and dry it under vacuum in a warm-water bath, with constant agitation; that's the method we use in our lab for drying heat-sensitive materials. Caution: drawing too much of a vacuum could chill the flask so much that it condenses moisture from the air and rehydrates the material. You should experiment with different suction pressure / water temperature combinations to see which one gives the shortest drying time without condensing moisture from the air. 98.234.126.251 (talk) 05:36, 9 September 2009 (UTC)

Have you investigated Fluidized bed techniques? Although these seem more commonly used for other purposes, it seems to me that they might also be efficacious for this one. Try searching the technical literature using this term. Actually, some of TenOfAllTrades's procedures may approach this area. 87.81.230.195 (talk) 19:58, 9 September 2009 (UTC)

I would like the OP to tell us what is the powder product that whose production we are asked to help, and whether this is a legal activity. Cuddlyable3 (talk) 13:01, 10 September 2009 (UTC)

Perfectly legal, I came here first in the course of researching companies to replace our current drying equipment. I would like to keep the product being made confidential but it is a reagent used in medical diagnostics. The equipment we use consists of a vacuum oven, which we do not heat, and acetone/dry ice-cooled moisture traps. This process takes 1-2 weeks for each batch to dry, which we are trying to find a way to speed up. Agitation while drying under vacuum would probably be best, but we are looking for specific manufacturers in the US which provide this type of equipment. I am sorry if the first post did not make that clear. To answer some questions above: we cannot heat the flask/oven due to the heat-sensitive nature of the product. We do currently use vacuum drying, but do not have equipment to agitate the product while doing so. The product is water soluble, and very hydrophilic, so drying is complicated by the tendancy of the product to absorb water from the air. Again, we are simply looking for suggestions of manufacturers who make vacuum drying equipment which agitates and possibly grinds the product while drying. Thank you. 134.217.112.15 (talk) 14:13, 10 September 2009 (UTC)

What you're looking for is a rotary evaporator -- unfortunately I don't remember off the top of my head which company made the one that's in our lab, and I didn't take a close look at the company logo. (In the lab, all of us just refer to it as "the rotavap machine".) Maybe if I have time, I could google some chemical equipment manufacturers to see if they make this kind of equipment. Please stand by, and keep this channel open. 98.234.126.251 (talk) 05:47, 11 September 2009 (UTC)

Oh, in the article on the rotary evaporator, it says that Buchi of Switzerland makes'em rotavap machines, so that company might be a good place for you to start looking. Good luck, and clear skies to you! 98.234.126.251 (talk) 05:51, 11 September 2009 (UTC)

Beginning of science: Aristotle or Galileo

Apparently, people with a humanistic background tend to consider Aristotle as the [] of science. On the other hand, people versed in the natural science consider Galileo the first scientist.--Mr.K. (talk) 16:07, 8 September 2009 (UTC)

It depends largely on what you define "science" as being. Strictly speaking, Aristotle bears little resemblance to a "scientist" by a primarily modern definition (he explained how he thought the world worked, and paid some attention to natural history, but he exhibited nothing like an empiricist ethos). Galileo looks a LOT more like a "scientist" than Aristotle did, though calling him the "first" is problematic (he was not totally novel, just very famous). In any case, the "science" of the Early Modern (Scientific Revolution) period looks a lot more like modern science than does Ancient "science", though even the Early Modern stuff looks pretty quaint compared to, say, 19th-century science (which is for all intents and purposes "modern", even though many of the things we currently associate with science are firmly rooted in the late 20th century). --98.217.14.211 (talk) 16:31, 8 September 2009 (UTC)

• History of Science is a good place to start. Seems like it really depends on what you mean by science. If you're talking about Natural philosophy, you have to go back to Thales. But Modern science starts at the Scientific revolution. Makeemlighter (talk) 16:36, 8 September 2009 (UTC)
  • It really depends on what tradition you are following. There were lots of early Arabic chemists, for example, doing real "Science" as before 1000 (see Muhammad ibn Zakariya al-Razi (aka Rhazes) in the 900's and Geber in the 700s. Even in Europe, Roger Bacon set out the basic precepts of the scientific method in the 13th century, 250 years before Galileo. If ANYONE is the father of modern western scientific thought, Roger Bacon is probably it, but even then I wouldn't make that assertion too strongly. --Jayron32 21:04, 8 September 2009 (UTC)

The greeks frowned on doing experiments - believing that you could simply think up all of the answers from first principles. That kind of thing works great for mathematics - but sucks when it comes to the physical sciences. Aristotle wasn't a scientist by any modern definition. SteveBaker (talk) 21:16, 8 September 2009 (UTC)

I agree generally, but there are important exceptions. Hippocrates (who might actually be a group of people, but it doesn't matter) was an amazing observer of empirical facts; and Archimedes was certainly open to experimenting. Looie496 (talk) 23:47, 8 September 2009 (UTC)

And Erastosthenes certainly didn't philosophize out the diameter of the Earth. Sagittarian Milky Way (talk) 00:50, 9 September 2009 (UTC)

Aristotle seems a pompous fool. No one person delayed the rise of the scientific method more than "the philosopher," as Aristotle was known many centuries after his time. Galileo was an empiricist and scientist. Edison (talk) 02:51, 9 September 2009 (UTC)

Unfortunately, Plato helped justify anti-science book burnings in later centuries by early Christians. Democritus, for example, was quite a materialist but hardly any of his writings has survived. 98.14.222.248 (talk) 22:13, 10 September 2009 (UTC)

For woman, does size matter?

I don't know many couples where the man is shorter than the woman. A well-known exception is Sarkozy and Bruni. Is that so important that the man is taller? On the other hand, I know several couples where the woman is making more money, is more intelligent, has more culture than the man. Mr.K. (talk) 16:09, 8 September 2009 (UTC)

Are you aware of an actual instance in which the woman in a couple has more "culture" than the man? Bus stop (talk) 00:25, 9 September 2009 (UTC)

I know plenty of couples like that - assuming Mr.K. means an interest in the arts, etc. by "having culture". Why do you ask? --Tango (talk) 00:33, 9 September 2009 (UTC)

I was just interested in seeing some actual examples. But you may be right — if we define culture as meaning an interest in the arts, then surely some examples can be found. While that may be the most common and basic definition of culture, it is by no means the only definition of culture. As we well know, culture often embraces the decidedly un-cultural. Maybe I'm nitpicking or being pedantic. But much of what passes for culture challenges our definition of culture. Bus stop (talk) 00:55, 9 September 2009 (UTC)

I agree that culture is far more than just the arts, but in the context of a person "having culture" I can't think of anything else that could be intended. --Tango (talk) 01:19, 9 September 2009 (UTC)

Yes, you are right. You make a good point. Bus stop (talk) 01:25, 9 September 2009 (UTC)

Two facts come into play here. First, because men are generally taller than women, the great majority of couples would have a taller man even if pairing were completely random. Second, there is (with many exceptions) a broad statistical association between tallness and social dominance, and a broad statistical tendency for men to be dominant (in the technical sense of the word) in relationships. Looie496 (talk) 18:31, 8 September 2009 (UTC)

Males are typically taller, but I think even that is possibly a RESULT of the thousands of years of selective breeding, not the cause of it. I think since women are the ones that give birth and breastfeed they are vulnerable at those times and so males play the role of the provider and protector. Males and females instinctually look for signs of health and virility in a partner, basically how suitable they will be for breeding with. A lot of what we find "attractive" these days stems from those ancient subconscious instincts. Some of those factors now get distorted, warped and manipulated by modern society since we no longer need to rely on "basic instincts" for survival. I think height is definitely one of the factors used as a indicator of health and vigour specifically in males. It's the iconic superman, fit and upright. In females the main factors are typically youth, breasts and hips, height is not necessary to make a good mother. In many other species the female is the bigger of the 2, I don't think there is any reason why female humans couldn't be the bigger gender on average if we bred that way for thousands of years, I think that baby nursing is the thing that prevented that from happening. Now I think there is definitely more of a trend away from the "classic" large hourglass shaped mother figure. It used to be that unless a woman had big hips she was much less likely to survive her first child birth, these days with modern paediatrics pretty much any woman can give birth relatively safely, so being skinny and tall is no longer a breeding liability. To specifically answer the question, no i do not believe it is "important" but it is a very strong left over instinct for a lot of humans. There will be expeptions to the rules as there always are, and the rules will slowly shift over time, but anyone claiming it is "important" is doing so based on reasons of purely human construct. Just like the belief that it is important to marry into your race. Vespine (talk) 23:08, 8 September 2009 (UTC)

"...signs of health and virility", yep. I once knew a couple who got married and between them probably maxed out the weight limit on a typic elevator. There's really no accounting for attractiveness. There's no absolute rule. Baseball Bugs ^{What's up, Doc?} carrots 00:13, 9 September 2009 (UTC)

Perhaps that was a case of you take what you can get. Googlemeister (talk) 14:19, 9 September 2009 (UTC)

Of course I wasn't suggesting there were any absolute rules, but that's a far cry from claiming there are no observable trends. Otherwise advertising wouldn't so heavily rely on sex to sell things. And as the above points out, in the scheme of things it makes perfect sense for two obese people to marry. The scenario which does not follow the trend is if a skinny person marries an obese person, but even the fact that this happens sometimes doesn't disprove the "trend", deviations from the norm are perfectly expected in any biological system, what would truly be strange is if there were no deviations from the norm. And I use the term "norm" in the purely statistical meaning of "average", not as an antonym of abnormal, that's an entierly different discussion. Maybe it is because people associate "norm" with good and "outside the norm" with bad that they are reluctant to admit the observable trends, but I think that's a fallacious association. "The norm" is not intrinsically superior to "outside the norm", it just means "average". Vespine (talk) 23:53, 9 September 2009 (UTC)

Aversion and fear

If you are afraid of something - dog, plane, spider or whatever - and you avoid any contact with or even approaching it, does your fear get bigger? If yes, why does it grow? Logically, if you don't have any contact with something, shouldn't the tendency be to loose any feeling towards it? --Mr.K. (talk) 16:10, 8 September 2009 (UTC)

I don't know if it would grow, but there's a good evolutionary reason why it wouldn't lessen over time (or at least not quickly). Let's say you come across an animal you've never seen before in the woods, and it nearly eats you. Even if you don't come across another one for years, if one day you do, it's important for your survival that you vividly remember your terrifying experience and stay away or else this time you might be lunch. That fear instinct is very important, so it can be hard to overcome even if we know rationally that a certain fear is illogical. Rckrone (talk) 18:02, 8 September 2009 (UTC)

The thing is that for somebody with a phobia, you think about the thing even if you don't have contact with it. A person with a spider phobia can lie in bed imagining that a spider might be about to crawl on them, and the idea can be so vivid that it is as fearsome as the actual event. This probably isn't a functionally useful phenomenon; it comes from having an overactive fear system. Looie496 (talk) 18:15, 8 September 2009 (UTC)

On the contrary — 'refreshing' the memory that way may be one of the mechanisms by which a person retains (evolutionarily-useful) responses to seldom-occuring but dangerous aspects of their environment (per Rckrone). I forget the original author, but I once heard an anology along the lines of: "Consider a small mammal living in the forest. Every time he sees a shadow move, he jumps. Nine times out of ten, it's the wind in the leaves, but one time out of ten it's a lion. The reflex action is still useful, because the penalty for jumping when the leaves twitch is much smaller than the penalty for not jumping when a lion pounces." Obviously, one can be too sensitive, to the point where one is leaping at shadows all the time and not eating; that's going to take an evolutionary penalty. But it's not clear where to draw the line between useful wariness and harmful paranoia. TenOfAllTrades(talk) 19:38, 8 September 2009 (UTC)

It could also be what psychologists call superstitious behavior. Running and hiding when you hear a noise averted the supposed danger. You run and hide everytime you hear a similar noise, and, lo and behold you angain "avoid being eaten," reinforcing the connection between fleeing the noise and staying uneaten. The counteracting principles are habituation and experimental extinction (of the learned response, not the wee fleeing creature). In humans, Cognitive behavioral therapy is a modern technique for lessening such self perpetuating associations.Edison (talk) 22:28, 8 September 2009 (UTC)

I think that's basically a different way to saying the same thing that I did. Concerning evolutionary utility, that's valid to a degree: there is data showing that phobias tend to focus on things that it is useful for monkeys to fear, for example snake and spider phobias are much more common than gun phobias. But it's important to keep in mind that not everything evolution produces is functional -- because each individual is a random mix of genes from the population, every so often you're going to get a combination of things that don't fit together very well. Looie496 (talk) 23:55, 8 September 2009 (UTC)

Having no fear can get you killed. Just ask Steve Irwin. Fear of spiders and snakes makes basic sense. These are two types of creatures that can hurt you, and if you avoid them you're less likely to get a venomous bite. The same principle, by the way, applies to speaking in public. Baseball Bugs ^{What's up, Doc?} carrots 00:10, 9 September 2009 (UTC)

Irwin did not die because he had no fear. Stingrays are not a creature that are particularly worthy of fear. I bet more people are killed by horses each year then stingrays. Googlemeister (talk) 14:17, 9 September 2009 (UTC)

Standard therapy for phobias of all kinds is gradual supervised contact with the feared object. Exposure builds up "evidence" that the item is harmless, thus outweighing the fear (based on a real experience or not) that it is dangerous. Constantly avoiding the feared object gives the person a one-sided view, reinforced by each occasion of deliberate avoidance. (If you don't leave home because you believe there are man-eating tigers in your (Northern Hemisphere densely populated) street, you will never find out that there are none). - KoolerStill (talk) 15:04, 9 September 2009 (UTC)

how to pump a longboard (skateboard)

i have heard that it is possible to "pump" a long board. in doing so you can basically move your longboard forward without ever having to push with your foot. when i heard this was possible i searched around the internet trying to find a good explentation on how to do this. i found websites but when i tryed i waas unsuccesfull. i figured if i knew exaclty why this is possible i would understand it better and might be able to pump my longboard. so exactly why is it possible? does it have to do with your momentum or is it something else? it would also help if someone could sugest a really good web site where i could get further explinations on how to preform this. thanks —Preceding unsigned comment added by 76.235.215.200 (talk) 17:45, 8 September 2009 (UTC)

It is just momentum shifting, like using a swing or twirling a hula hoop. I was going to go into a detailed description, but thought I'd check to see if Google was nice and found one on ehow here (can't link straight to ehow - it is blocked). -- kainaw™ 18:11, 8 September 2009 (UTC)

Note: this is presented as observation and not advice, since falling is fairly likely while practicing a new technique. It reminds me of a way of skating along while keeping the iceskates parallel, but shifting from one edge to the other. On the board if the axis of the board points to the right, then a push to the right by dropping a bit and rising back up, will result in some forward resultant. Flip the board a bit to the left and pump left. Edison (talk) 22:23, 8 September 2009 (UTC)

Asian (Indian) elephants and African elephants

Often in the media, we see Asian (Indian) elephants being used as a beast of burden (and other positive interactions with humans). However, I have never seen the same for African elephants. Is there a reason for this? Are Asian elephants easier to "domesticate" while the African elephant can not? —Preceding unsigned comment added by 69.77.185.91 (talk) 18:36, 8 September 2009 (UTC)

Well, just about all domestic elephants are female as the male is more aggressive. Perhaps African elephants are more aggressive then the Asian elephants. Our articles do not determine this. Googlemeister (talk) 19:53, 8 September 2009 (UTC)

Male elephants also periodically enter musth and go into 'kill everything that moves' mode... --Kurt Shaped Box (talk) 20:07, 8 September 2009 (UTC)

(after ec)According to this - "When the Belgians in colonial times intended to stub the jungle of Belgian Congo, they employed Indian mahouts, who successfully caught and trained the African elephants according to the Asian method. Nowadays safaris on the backs of African riding elephants become more and more popular in Africa". This article says that despite the common belief in Africa that they're untamable, the African Elephant is "with patience, quite trainable" and also notes that Hannibal battled the Romans with AEs. Well, I don't suppose that he would've have done that unless they could be reliably trained not to panic and run amok when the javelins started flying and indiscriminately trample both friend and foe on the battlefield... --Kurt Shaped Box (talk) 19:58, 8 September 2009 (UTC)

It's also possible that the societies of Africa put their trust into more trustworthy beasts of burden, such as buffalo. DRosenbach ^{(Talk | Contribs)} 20:41, 8 September 2009 (UTC)

There also may be the consideration as to whether the benefits of African Elephant's extra strength and work capability when compared to other beasts of burden justified its huge daily food requirements. --Kurt Shaped Box (talk) 21:03, 8 September 2009 (UTC)

... and huge output at the other end! Dbfirs 23:01, 8 September 2009 (UTC)

Fertilizer. --Kurt Shaped Box (talk) 23:24, 8 September 2009 (UTC)

Mosquito repellent and fuel // BL \\ (talk) 02:47, 9 September 2009 (UTC)

Not to mention a (semi-)drinkable watersource. 124.154.253.31 (talk) 04:22, 9 September 2009 (UTC)

The African buffalo is only trustworthy if you're trusting it to kill you. --Sean 16:47, 9 September 2009 (UTC)

Actually, War elephant says they did indeed have a tendency to panic and run amok. AlmostReadytoFly (talk) 08:51, 9 September 2009 (UTC)

Well, throw enough spears at any large animal and it's eventually going to lose its cool - but the point that I was trying to make is that unless the elephants could be conditioned not to behave like this for the most part, they'd be absolutely useless as war mounts and a complete liability on the battlefield. The fact that it was even possible to lead them into battle in the first place shows that they can be trained... --Kurt Shaped Box (talk) 15:02, 9 September 2009 (UTC)

The point I was making was that although they can be trained to some extent, they frequently have been a liability on the battle-field. In contrast, I don't think (arguing somewhat from ignorance here) horses have been criticised as much for this. AlmostReadytoFly (talk) 15:32, 9 September 2009 (UTC)

Agreed there. A panicked, out of control horse isn't going to accidentally (or deliberately) kill/maim 15 guys in the space of a minute or so as it tries to flee. As a side issue, I wonder how rogue elephants on the battlefield were dealt with in ancient times? Did the soldiers try to kill the beast, or did they get out of its way as fast as possible and let it run off into the distance (then perhaps attempt to catch it again later once it had had time to calm down)? --Kurt Shaped Box (talk) 20:21, 9 September 2009 (UTC)

Opposing armies probably let them run away, but the army using them wouldn't want their own troops crushed/killed. The War elephant article says "The driver, called a mahout, was responsible for controlling the animal. In many armies, the mahout also carried a chisel-blade and a hammer to cut through the spinal cord and kill the animal if the elephant went berserk." 12.34.246.72 (talk) 15:38, 11 September 2009 (UTC)

Be careful not to confuse "domestication" and "taming". Strictly, a species is only domesticated when it is bred in captivity and the captive-bred population shows physical and/or mental modifications from the wild population. By contrast, wild-breeding animals can be tamed, and trained, to the extent that their species' and their individual innate natures render them amenable to being so.

In all history, only the long-vanished Indus Valley Civilization (aka the Harrapans) are known to have successfully domesticated the (Indian) Elephant. Otherwise, elephants have been successfully bred in captivity only rarely, and most of the (mostly female) working elephants in India and elsewhere have been caught and tamed, although some have been born to tamed females allowed to mate with wild males. Our articles on Domestication and on the Asian Elephant are guilty of some loose and inconsistant language in this regard. 87.81.230.195 (talk) 19:28, 9 September 2009 (UTC)

As a separate point, note that although African elephants were used as war elephants in the Mediterranean sphere (to which Asian Elephants were also imported), these were usually the North African Forest Elephant, a species or sub-species now extinct (not least because of this exploitation) which was somewhat smaller and probably more tameable than the surviving African Forest Elephant and even larger African Bush or Savannah Elephant. 87.81.230.195 (talk) 19:41, 9 September 2009 (UTC)

Biochemistry question: What does oxygen do in this case?

After oxidating glucose into CO2 and water, oxygen helps it become stable because of the oxygen even though the accumulative G0 value is largely NEGATIVE...how's that possible? —Preceding unsigned comment added by 93.183.239.108 (talk) 19:25, 8 September 2009 (UTC)

See Gibbs free energy. A negative G value means the reaction is favored, so as far as I understand your question, a negative G makes perfect sense. If not, please elaborate on your question. The Seeker 4 Talk 19:37, 8 September 2009 (UTC)

Indeed, a negative gibbs free energy means that the reaction is spontaneous in the forward direction. Read Gibbs free energy for more info. --Jayron32 20:58, 8 September 2009 (UTC)

Peroxisome

What is "microbody family"?174.3.110.93 (talk) 22:07, 8 September 2009 (UTC)

Have you read our article on microbody, linked from the peroxisome article? TenOfAllTrades(talk) 22:26, 8 September 2009 (UTC)

It appears to mean the group of things called microbodies. See the 8th meaning of family on Wiktionary. AlmostReadytoFly (talk) 11:49, 9 September 2009 (UTC)