Mokele

I'm not sure why it would be, though? I mean, regardless of how long a species lives, it's still got to compete on the short term, and that's where evolution takes place. I mean, if a new, mutant turtle (not necessarily a teenage ninja one) arises with half the lifespan of it's conspecifics, but with twice the reproductive sucess, it'll profit and become more common, eventually replacing the older form. Perhaps populations or a species that hadn't yet evolved a particular short-term benefit might do better than other populations of the same species with that short-term benefit in species-level selection events (like famines or asteroid strikes), but any migration between populations would bring a superior short-term competitor in. Mokele

Complete with court jesters, known then as 'hippies'. I actually haven't tried reading it yet, though maybe one day. While the concept of reading original works and examining them for myself in order to have a more thorough grounding in the basis and origins of the concepts I use appeals to me on an abstract, intellectual level, on a more pragmatic level I simply don't have time, and what time I do have can be better spent learning more current information in my field of interest, rather than reviewing information that has already been fact-checked and confirmed thousands of times. Plus it's boring. At least to me, since in Mokele-land, 'not containing info on reptiles' = 'boring'. Mokele

I think it would be more accurate to say that complex social interactions lead to the development of what humans consider 'inteligence'. I've met individuals of primarily or partially asocial species (such as monitor lizards and crocodilians) that put dogs and cats to shame in terms of raw problem-solving, yet we consider those species "dumb" because they aren't as "interactive" (except when trying to kill us). Mokele

I suspect it's a joke, but it's not very funny. Or at least I don't get it. Or it's just plain facetious stupidity. Mokele

You're a braver man than I. I got about halfway through and stopped. I just couldn't take any more crap about pigeons. Then again, I absolutely *loathe* the Victorian English writing style, so no suprise. You might want to try a book called "Darwin's ghost". The author basically re-wrote the Origin, but using modern data and knowledge, while staying true to the format of Darwin's work. Much more readable and understandable, plus more up-to-date. Pretty much, yeah. That's why evolution studies often involve bacteria and fruit-flies, as opposed to tortoises. They go through so many generations so fast that evolutionary change becomes very obvious in time to get a paper out. Mokele

Yes, but the bacteria still go through boom and crash cycles, because it's beneficial on the short term. That's my point, the immediate advantage is what evolution works on, even if it has negative long-term consequences. Say we have a population of organisms with limited resources, like the aforementioned bacteria. Due to natural variation, some bacteria are going to reproduce faster than others. These will become an increasingly large part of the population, as the population booms. Then it crashes. If there's no difference in mortality and simply a certain percentage die, the fast-reproducers will continually become a greater portion of the population, even though it accentuates the boom and bust cycle. If one of the fast reproducers mutates to be a slow reproducer, which would dampen out the boom bust cycle, it'll be outcompeted because, while it's strategy is good for the whole, the others will still produce more offspring. Similarly, if an even faster, super-reproducer mutant occurs, it would further accentuate the boom-bust cycle. But self-restrain doesn't pay in evolution; the super-reproducer would produce more offspring and eventually become the entire population. What I'm saying is that evolution doesn't act on the long term, for-the-good-of-the-species level, it acts on the short term, who-can-have-more-kids level. This may produce diasterous results, as the example you supplied indicated, but self-restraint is self-defeating; those organisms that don't compete effectively on the short-term will never get a chance to influence the long term. Mokele

Yes, having a lower body heat *would* make us more efficent. We would use less than 1/10th of the energy we do now, and need to eat approximately 1/20th as much, if we maintain the same activity level. However, without burning food to make heat to keep ourselves warm, movement would be the main source of energy consumption, so by simply not moving, you could cut your already lowered energy consumption by at least a factor of 3. Welcome to the amazing efficiency that is Reptilia and Amphibia. There's a reason that your average endotherm only converts 2% of the biomass it takes in into new biomass (growth or reproduction), versus an average of 50% for herps (reptiles and amphibians). However, like everything, there's trade-offs. Ectotherms pay for this efficiency by becoming, in effect, slaves to the sun. Most are dinurnal, and all have to spend a significant amount of time thermoregulating to maintain their body temperatures. They can exploit niches that mammals cannot, becuase as mammals get smaller, it costs more and more to maintain a stable temperature, yet reptiles suffer no such metabolic barrier to miniaturization. Also, mammals can exploit colder climates than herps. But herps have a far greater mastery of the water, due to their greatly reduced oxygen requirements. The biggest one, though, is aerobic scope. Say you're walking at a slow speed. You can continue to do this for a long, long time, without exhaustion. If you increase your speed a bit, it's the same, no exhaustion. But at a certain point, your body can no longer supply enough oxygen to maintain your metabolism at that speed, and you switch to anaerobic metabolism (at least in part). Now your endurance is substantially lower, and you're vulnerable to cramps. Further increases in speed serve to reduce your endurance more and more. The range up until exhaustion becomes a factor is called your aerobic scope. Now, apparently, aerobic scope is universally 10 times your resting metabolic rate. For organisms with a low resting metabolic rate (like a lizard), that means anything beyond a casual walk is anaerobic, and, while lizards can still move *very* fast, they cannot sustain high-speed activity. In contrast, a human, with a high resting metabolic rate, can run at moderately high speeds and still not have to worry about exhaustion (at least not for a long time). The maximum speeds may be the same, but for intermediate speeds, mammals have a strong endurance advantage. This allows them to function as much more active, wide-ranging animals than reptiles. But they pay the price for it, in terms of increased food requirements. So, basically, each side has advantages and disadvantages, and which outweight the other depends on the ecological niche in question. Mokele

But the long term is irrelevant. Selection works on the individual (usually), and even if there's a long-term disadvantage, a trait will increase in frequency if there's a short-term advantage, especially one that overbalances the long-term, species-level disadvantage. However, I do think you're going in the right direction. I'd say, instead, that, once K is reached, the competition and other factors are so intense that non organism gets a chance to be immortal; they all die of predation or stravation or parasites or similar environmental insults in reasonable time. Immortality would require cellular machinery to maintain it, and mutations would occaisionally disable that machinery. If the lifespans of organisms with and without these hypothetical "immortality genes" aren't different due to the intense competition and high mortality rate, then "non-immortals" won't suffer any penalties. In fact, since they don't 'waste energy' on this maintenance, the 'non-immortals' might actually be at an advantage. Thus, the loss of the hypothetical cellular machinery for immortality would be selected for, and eventually such machinery would just disappear. Mokele

Had they survived as anything more than birds, we'd still be little shrew-like critters scurrying about their feet. However, if they hadn't gone extinct, it may have been possible for a taxa of dinosaurs to evolve civilization. Of course, their civilization would have been much different than our own. Mokele

He's asking us to do the problem for him. In principle, this is the same as copying off someone else, just facilitated by the information age.

Swansont: The Kinetic energy *does* stay the same in an inelastic condition. The object just "gains mass" via the collision. KE = 0.5*m*V^2 KE is the same before and after, but m increases, so v must decrease. If you're doing it right, you'll get the same answer as with conservation of momentum. budullewraagh: While I sympathize with your plight, that does not justify what amounts to copying your homework from a friend. If someone else wants to simply hand you the answer for you to copy down, that's fine, but I prefer to keep my academic integrity. Mokele

There are also people who think they're the re-incarnation of elves from other planets. People believe stupid $#!+ all the time. Mokele

Use kinetic and potential energy to solve it. That should give you the answer pretty simply. Remember that the energy remains the same when tarzan grabs jane, so if his mass increases by picking her up, his speed will decrease.

Not always. While the tradition of marriage is religious in origin, the meaning of any particular marriage is primarily up to the couple in question. Some do indeed see it as a religious contract, but others view it as merely an expresssion of love, devotion and desire to build a life together. The latter is the view of my GF and myself, and given that we're both atheists, it can be pretty well assured to be devoid of religious content. Mokele

From a prof sharing lab space with my prof: If you aren't part of the solution, you're part of the precipitate. Mokele

Correct me if I'm wrong, but weren't the reports of weird weather in CA starting from *before* the tsunami? I'm fairly sure they were, as I was keeping tabs on that at the time (my GF flew back to CA in that time frame, hence the attention). If the odd weather started first, the tsunami can't have caused it, right? Mokele

Maybe, but I'm much more inclined to chalk it up to simple variation and natural selection. Most animal populations display a pretty wide range of individual sizes, even when you take out environmental factors. Given that, if selection begins to favor one size extreme, you could expect the population to evolve in that direction at a fairly brisk pace, evolutionarily speaking. Mokele

In canada, the drivers at a red light stop their cars *behind* the crosswalk, not *in* the crosswalk. Mokele the irrate pedestrian

Not necessarily. All you need to know is how to manipulate the school administrators. With the new emphasis many schools have on "anti-bullying" stuff, if you cast yourself as the victim merely fighting back, you can often win. I was never that good of an actor, but I'd say that manipulation authority figures into doing your bidding is one of the best things you can learn in school. Mokele

There's also another option: We still have lethal genetic diseases. Why haven't they died off? Mutation. While selection removes the genes from the population, mutation creates them again. However, most mutation-selection balances result in very low gene frequencies, much lower than the rate of homosexuality in the world, so I don't think it's a good explanation in this case. But it does go to show that genes which reduce fitness can stick around. Mokele

You missed the point. The point was as a "What if" exercise. As in "It probably doesn't exist, but *if* it did, what would it be?" It's a hypothetical question.

Cancer cells, while immortal, also have other specific characteristics, mostly related to the control of the cell cycle (or lack thereof), Most cells in a metazoan grow, then replicate their DNA, then grow some more, then divide. Getting to replicate the DNA, or even really do any of that (as opposed to just chilling out at the same size), is controlled both internally and externally. The relevant external controls have to do with, for instance, space; if there's not enough room, they don't divide. Cancer cells lack these controls, due to genetic damage, so they just divide as fast as they can, and grow as big as they can. Stem cells have these controls, so they don't divide uncontrolably. However, telomerase-producing adult stem cells do already have one of the ways of becoming cancerous, which is why cancer occurs most often in tissues with such stem cells rapidly dividing, such and the bowel or epidermis. Mokele

I found a tidbit in The Straight Dope (which I consider pretty reliable, given it's myth-busting theme): "Between 1975 and 1992 military satellites detected 136 objects between 30 and 50 meters in diameter exploding in the upper atmosphere." Mokele

I disagree that anyone who is capable of killing another person in such a circumstance is psychotic or somehow unhinged. For instance, joking aside, I strongly suspect I could or would if I felt threatened enough, not because I'm some sort of psycho, but simply because I know I am willing to harm others in self defense, and if my only self defense item around is lethal, I'll use it. I'm not gonna shoot them in the head from behind or something, but, given a situation in which they posed a definite threat which could potentially be lethal, I see no reason why I wouldn't respond with lethal force, if that was my best option. I am probably *more* than skilled enough in martial arts to take out an unarmed opponent, but not nearly stupid enough to try, because a guy with a gun hidden on him looks unarmed. I do feel a purely ornamental sword my folks gave me could be of use, but simply because it's a 3 foot long piece of metal. Damascus steel or a chunk of rebar, it'll still hurt someone if you clobber them with it. Also, to be honest, their life is not as important as mine, because it's mine. If they die, I feel bad. If I die, well, I'm dead. Yes, it's selfish, but that hardly makes me any worse than any other person, merely more honest about what motivates me. I've heard of this too, and I'm partial to it myself, enough that it's be my prefered means of home defense (strong deterent and likely incapacitating without being lethal or even strongly damaging). However, while I've heard of it before, I'm skeptical. Does it really work? Is it really non-lethal? Is it a truly effective deterent? I know it *should* be, in theory, but I know enough not to trust purely theoretical designs without testing them. Especially when it could be my life on the line; I don't want to find out that it's an urban legend when someone's coming at me with an axe. So, does anyone know of any hard evidence that it works in practice as well as theory? Mokele

Actually, from what I've read, they are common, but often occur so high in the atmosphere that we never see them due to the typically small size of the objects involved. Iirc, some government agency that actually watches stuff up there (NORAD, I think) was reported as seeing about 800 such events a year. These are what mostly interests me, more than just hitting the ground, and were actually why I started the thread Mokele