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bombus

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Posts posted by bombus

  1. It's as big an issue as there is in the entire universe, but it's totally irrelevant to the computability of consciousness...

     

    Yes, it is as big an issue as there is in the entire universe - and that's the point!

  2. Victor J. Stenger' date=' writing in The Humanist, May/Jume 1992 harshly dismissed the Quantum Mind saying:

     

    "The overwhelming weight of evidence, from seven decades of experimentation, shows not a hint of a violation of reductionist, local, discrete, non-superluminal, non-holistic relativity and quantum mechanics - with no fundamental involvement of human consciousness other than in our own subjective perception of whatever reality is out there. Of course our thinking processes have a strong influence on what we perceive. But to say that what we perceive therefore determines, or even controls, what is out there is without rational foundation. The world would be a far different place for all of us if it was just all in our heads - if we really could make our own reality as the New Agers believe. The fact that the world rarely is what we want it to be is the best evidence that we have little to say about it. The myth of quantum consciousness should take its place along with gods, unicorns, and dragons as yet another product of the fantasies of people unwilling to accept what science, reason, and their own eyes tell them about the world."[/quote']

     

    Victor J Stenger obviously hasn't noticed that we DO 'make our own reality.' If I choose to do something reality becomes one where I have chosen to do that something. If Hitler had not decided to enter politics WW2 wouldn't have happened. Obviously we can alter reality by our actions - and IMO that is done by altering reality in our brains i.e., collapsing wave functions by using our conciousness. The consiousness of one individual can only effect very small things with a high degree of randomness. I cannot make (by effort of willpower) a car change into a banana, but I can probably alter the position or direction or state of an electron - especially one in my brain. This is how we are able to control our thoughts. This is the point. This is the reason. This is why the double slit experiment is such a puzzle. Of course brains function on a quantum level. It's useful - why d'you think people are desperately trying to build a quantum computer! Evolution got there years ago!

     

    The alternative is that everything is predetermined, and conciousness and free will are just a biochemical illusion. Every single thought or action in the universe is pre-determined and we are lucky enough not to realize.

     

    Either one could be true, but I know which one I'd rather believe. Ultimately its all down to faith you know...

  3. However' date=' from Penin X, Berge C, Baylac M. [u']Ontogenetic study of the skull in modern humans and the common chimpanzees: neotenic hypothesis reconsidered with a tridimensional Procrustes analysis.[/u] Am J Phys Anthropol. 2002 May;118(1):50-62. we have this observation:

     

    Thus, the reduced prognathism, the flexed cranial base (forward position of the foramen magnum which is brought closer to the palate), the reduced anterior portion of the face, the reduced glabella, and the prominent nose mainly correspond to functional innovations which have nothing to do with a neotenic process in human evolution. The statistical analysis used here gives us the possibility to point out that some traits, which have been classically described as paedomorphic because they superficially resemble juvenile traits, are in reality independent of growth.

     

    In short, let us be wary of fashion in science.

     

    Link: http://www3.interscience.wiley.com/cgi-bin/abstract/93013173/ABSTRACT?CRETRY=1&SRETRY=0

     

    Let us also be wary of single scientific papers which possibly hint rather than prove! Although some of the traits mentioned above may well be the result of other processes rather than neoteny. The human spine/skull articulation is unlikely to have arisen via any other process though IMO.

  4. Well' date=' since I started this thread last February, I was pleased to see that Wikipedia has developed a nice article about Neoteny.

     

    http://en.wikipedia.org/wiki/Neoteny

     

    Would still like to know more, especially about neotenous traits in humans, but it's a start.

     

     

     

    Baldur[/quote']

     

    Well, there are many possible traits:

    The fact that we are hairless may be one, also our subcutaneous fat, big brains, long noses, small jaws, a skull that articulates at the centre rather than towards the back (compare a baby ape to an adult), crying, tears, our curiosity and playfulness even as adults, possibly our foot design...er.. can't think of any more...

     

    Our neoteny may be due IMHO to a semi aquatic ancestry, but thats a different thread - see below!

  5. I'm completely against introducing ID into the classroom, but this last line, especially was interesting, I think it provides the strongest argument for Prof. Behe, despite the fact that it's still flawed.

     

    No, its not a strong argument really. Its just that we are all actually just brains and everything we perceive is subjective through our various organs. We could all be just brains in jars or even just algorithms in a big computer game.

     

    The point is, science is based on accepted truths because we have to start somewhere and the basic truth is that what we perceive is real, and what we can't perceive is irrelevent. From that base, science is built upon experimental proof and is able to predict. ID is not based upon any experimentation and cannot predict (unlike natural selection as a theory of evolution which can be proven via genetic experimentation and predictions which can be checked).

  6. Are cows parasitic on grass then? I suppose it could be mutualistic symbiosis, as grazing stops other plants colonising and shading out the grass (which is good for the grass), but at the same time prevents the grass from flowering and seeding (not so good). There is only benefit to the cow.

  7. Triple or quadruple helices are unlikely to evolve as a standard as they are not generally needed as the having two works fine, and nature likes to keep things as simple as possible. That's why we only have two eyes to produce binocular vision (more than two is of no benefit) and two sexes (hermaphrodites are just two sexes in one creature) and ...err...other stuff. I'm sure you can think of other examples.

  8. How does the presence of one intelligent species affect the evolution of a second species towards intelligence? I think that man's intellectual development alters the selective pressures for intelligence in other species. I don't see another species gaining our level of intelligence on Earth mainly because we'll drive those candidate species to extinction or relegate them to small zoo populations.

     

    We already have killed off other intelligent life forms, the last being Neanderthal man! Ok, technically the same as us, but it signifies how ruthless we'd be with any other intelligent rivals.

  9. You may be right, but as intelligence is so useful it may be inevitable eventually wherever life exists. However, intelligence (sentience/sapience) may actually be a really bad idea as perhaps intelligent creatures always destroy themselves one way or another. We are destroying our environment and although we know it ('cos we are so intelligent!) we seem unable to stop ourselves due to basic human nature.

     

    Life may carry on but we (Homo sapiens sapiens) may be gone in 500 years, and so would have existed for less than 50,000 years! Would we even show up in the fossil record when intelligent land dwelling octopi start developing their own theories of the 6th great extinction!?

  10. So' date=' let me get this straight: Someone points out that non-aqautic apes and monkeys (and even dogs) can hold their breath, which casts doubts on the AAH, and you respond by asserting they can't because of the AAH? You're kidding, right?

     

    Sorry, but evidence takes precedence over theory. If data shows that non-aquatic apes can hold their breath, that punches some big holes in the AAT, which cannot be circumvented by simply denying the data.

     

    No, I am not saying that. I am simply saying that the AAT refers to apes, our closest ancestors, not other animals, so the studies referred to are irrelevant in that sense. You'd need to prove that chimps can hold their breath voluntarily under water - and exhibit a dive response while your at it. We all know other animals can e.g. seals, otters, mink, water voles etc.

     

    This coming from someone who wants to ignore evidence because it conflicts with their pet hypothesis?

     

    And' date=' FYI, it's a hypothesis, not a theory. Only once fossil evidence supports it will it become a theory.

     

    Not my pet hypothesis at all - just more likely than the savannah theory (on its own that is - I am sure the savannah theory is part of the story). Also it does not need fossil evidence to be a theory - any evidence will do! It was not fossil evidence that makes evolution a theory because the fossils themselves prove nothing - its just how they are interpreted - which is open to question - ask a ID proponent!

     

    Please support this assertion. The only animals I am aware of which undergo neoteny in response to adapting to an aqautic life are salamanders. Even reptiles don't.

     

     

    You are confusing 'metamorphic' neoteny and evolutionary neoteny. Evolution can 'use' neoteny to get a result e.g' date=' to get a big brain, resemble an infant (in proportion) which has a bigger brain compared to the body than adults. Or, need fins instead of legs? Simply have shorter legs in comparison to your body (like infants) and over millions of years you turn into a dolphin, or whale, or whatever. If you don't understand what I'm going on about please read up on it. Some say it is an alternative theory for human evolution, but its more of a process than a complete theory because it needs a reason to work. it can be incorporated into both the savannah and aquatic ape theories.

     

    Given that there is no fossil evidence concerning the hairiness of any hominin, that cannot be used to support any theory. Hair may have been lost immediately after the split or only after H. sapiens evolved; we have no fossil skin impressions to tell us anything more.

     

    Yes I know that' date=' I am just saying what the AAT requires. Obviously we don't know when we lost our hair, but if it the AAT were true, the hair loss would have most probably occurred way before Homo erectus evolved. That's all I'm saying.

     

    You've got it wrong-way around. We have flipped-shpaed feet because feet evolved *from* flippers, back in the Devonian when vertebrates first crawled out of the sea.

     

    You seem to be showing a lack of knowledge about evolution. The 'aquatic ape' would have started with feet like chimps' date=' or gorollas. However, in one sense you are right. By 'using' neoteny we could have reverted back to 'embryonic' feet which would have resembled our very distant fishy ancestors.

     

    Wrong. Valves that seal the nostrils are a *VERY* common adapation, seen is just about every aquatic and amphibious species. Why don't we have them?

     

    Seals are almost totally aquatic so have evolved 'closable' nostrils as they have been aquatic for a very long time. We would not have been aquatic (or semi aquatic actually) for very long. Maybe if we had stayed in the water for a few more million years we would have developed closable nostrils. Humans only got as far as a nose that has a 'flap' at the front to stop water entering when swimming. Actually' date=' the proboscis monkey is a relatively good swimmer (for a primate) and has a big nose as well!

     

     

     

    So can dogs, and they're *definitely* not adapted for an aquatic life.

     

    We are not adapted for an aquatic lifestyle nor were our 'aquatic' ancestors adapted for a life totally in water! We would have just developed some minor characteristics that helped a little. e.g. flipper like feet (but not flippers)' date=' subcutaneous fat (but not blubber), a long nose (but not closable nostrils) ability to hold our breath and have a dive response (but not anywhere near as well as a seal or dolphin) etc... I think you misunderstand the Aquatic Ape Theory! Maybe it should be renamed the 'semi-aquatic ape theory', or to really clear the 'ape that spent very long periods of time in water theory'.

     

     

     

    Actually, we naturally float face down. See corpses.

     

    Corpses are dead. Even dead dolphins just float about on the surface. On still water a human can lie on its back and its head tilts naturally back leaving the nose and mouth above water. Try it next time you swim' date=' just relax and it happens! This is actually a well known fact - nothing to do with the AAT theory as it was known way before.

     

     

     

    I don't think sweating as actually any worse than any other method mammals use. Panting and sweating *both* use evaporative cooling, so you'll need to dump just as much water either way.Mokele

     

    Yeah, but panting can be controlled when things get tough. Sweating can't. Also, the amount of water lost through panting is nowhere near what humans lose through sweating. As I said, sweating is a brilliant way of losing heat quickly, even better if hairless, but only good if you can carry water around with you.

  11. I have thought about this a little bit and I am more convinced than ever that hominids lost their hair in order to lessen the strain of reducing excess body heat.

     

    Hair reduces the body’s ability to cool itself by reducing the cooling capacity of:

     

    1) Convection

    2) Evaporation/Sweating

     

    The Savanna environment required more efficient means for the hominids to cool themselves because:

     

    1) The increase in body temperature due to direct sun radiation

    2) The greater distances traveled during scavenging compared to the lush jungle.

    3) The need to run from predators.

    4) Evaporation/sweating became incredibly more efficient in the dry Savanna environment and hair interferes with the heat reduction from sweating.

     

    Some other savanna animals didn't require as much heat reduction efficiency from sweating as hominids' date=' and thus didn't benefit as greatly from total hair loss because:

     

    1) They pant, which is an effective means of heat reduction for many animals, but not hominids.

    2) They were nocturnal while man is usually active during the day.

    3) They had more efficient gaits. Animals like lions and zebras have graceful and energy efficient walks and runs, while early hominids were still adjusting to walking greater distances and walking semi to fully effect on two feet. This means that animals like Zebras expelled less energy for equal amounts of effort.

    4) They had smaller brains. Brains require a lot of energy per weight and the hominids were already developing great brain to body size ratios compared to other animals. The modern human brain uses 25% of the body's energy and therefore generates 25% of its heat while only weighing about 3 pounds.

    5) Other animals have evolved other methods to cool themselves, like wading in mud.

     

    Additional reasoning:

     

    1) Chimpanzees and apes have very sparse hair density compared to other mammals with hair. The amount of hair reduction through shortening is comparable to the amount of hair reduction and shortening in other savanna animals, compared to their colder climate counterparts. As an example I provide a link that has pictures of African dogs and cold climate wolves and a picture of chimpanzees, so that you can observe the differences in hair density: http://www.denverzoo.org/animalsplants/mammal02.htm

    [img']http://www.exzooberance.com/virtual%20zoo/they%20walk/chimpanzee/Chimpanzee%20485083.jpg[/img]

     

    2) Evolution has no foresight, nor is it perfect. While developing denser yet shorter hair like many other savanna animals may have been the most optimal choice for man, evolution does not plan out its strategies. Natural selection selects most strongly for the characteristics that are influencing survival and procreation the greatest at that moment in time. Men were dying because of heat exhaustion and lack of endurance because of the extreme heat so Mother Nature selected men with shorter, thinner hair for survival.

     

    3) Men eventually developed the intelligence and knowledge required to make clothing and shield himself from the cold. At one point in time man had a very efficient means to protect himself from the cold, but no means to efficiently protect himself from the heat. Animal skins were a removable replacement for the warmth of hair and thus removed one of hairs greatest benefits.

     

    Criticism for the lice theory:

     

    1) Most land mammals are exposed to vermin like lice and flees. We know that hair makes infestations worse because it provides an environment favorable for breeding, hiding, and holding on to. However, regardless of the negative effects of vermin like lice, most mammals still have hair because the temperature regulation benefits of hair trumps the problems associated with it.

     

    2) Since chimpanzees already have an effective means to remove lice, from grooming, it is likely that man's ancestor also used similar methods to remove lice. Since man's ancestor already had means to hold lice infestations in check, the selection for genes that reduced the deaths associated from infestations would not be strong so it is less likely that lice infestations were the biggest factor for the hair reduction of hominids.

     

    3) No apes that I'm aware of have lost their hair like humans, yet they are constantly exposed to lice. If hair was causing more problems from lice than it solved it, we would probably see more naked ape species.

     

    4) Jungle environments are fertile grounds for lice. I don't believe that hominids experienced more problems with lice after they moved to the savanna. But hominids definitely had problems with heat after he moved to the savanna. Furthermore, we see a clear correlation between other animals’ amount of hair and the temperature. So we see a clear correlation between temperature and hair, but no correlation between lice and hair.

     

    Criticism of the Aquatic Ape theory:

     

    We have found many fossils of Homo erectus around coastland. In fact, it seems like he spread out following the coast. However, hominids probably did not loose their hair do to the effects of the ocean.

     

    1) Hominids were beach combers, not ocean swimmers. Homo erectus used stone tools, so cracking open crab and oyster shells probably provided a useful sustenance. But combing the beach is not the same as living in the ocean and water adaptations like loosing hair would not have occurred.

     

    2) Hominids spent very little time in the water swimming. Hominids had no reason to spend more than a little time in the ocean because they were probably at least as bad at swimming as we are. They couldn't catch any fish with their hands and the amount of time spent in the ocean diving for clams and such was probably not significant enough to cause radical changes.

     

    3) Hominids don't have obvious adaptations to water but they have obvious adaptations to heat. We don't have webbed feet or sea-water resistant skin, but we do have a lot of sweat glands. Chimpanzees don't have near the capacity to sweat that humans do, so it was very important at one point to be able to cool down. We don't find these same kinds of obvious adaptations to spending a great deal of time in the water.

     

    A few points in no real order:

     

    If losing heat was the reason, our heads would have been the first place to lose it and bald men would be seen as extremely sexy!

     

    Re: Aquatic ape theory:

     

    Points 1 and 2) We would have lost our hair long before Homo erectus evolved. Think of the common ancestor of us and chimps - its around then it would have happened.

     

    3) We have flipper shaped feet - great for swimming and also pre-adapted for life on land. We also have a nose that stops water going straight up the nostrils. We can hold our breath. If we lie still in water we naturally float with our mouth and nose just above water. Human babies can swim as soon as they are born (they really can!). Lots more stuff that I won't go into here!

     

    Sweating is a great way to lose heat on a savannah once you are a bipedal hairless ape with the intelligence to carry water with you (or dig to find it). Its a crap way to lose heat otherwise as one dies of dehydration very quickly. I doubt it would have evolved just as a result of being on a savanah.

  12. The parasite idea is unlikely to be the reason. It would apply equally to apes and they still have hair. Also, they are usually picking off salt crystals from each other - not ticks and fleas as is commonly thought.

     

    Human evolution is, however, mostly due to sexual selection. The question is why were certain features thought of as sexy? Someone earlier made the point about hairlessness being a by product of having a big brain and I think that is at least partly correct. But having a big brain would be an advantage to any ape, so why didn't chimps and other apes get bigger brains when we did? Something happened around 5 million years ago that made us get big brains but didn't work for other apes.

     

    There is the Omega 3 fatty acid arguement which I am sure is correct, and seafood is rich in Omega 3. That might have been enough, but somehow I think it would have required more. I think a semi-aquatic lifestyle pushed our ancestors into liking neotenic features. Dolphins, Whales, seals, sealions, otters, elephants, hippos, - all exhibit neotenic features to varying degrees, as it is helpful for an aquatic (or semi aquatic) lifestyle. Once pushed in a certain direction, sexual selection has done the rest and our brains have got bigger and bigger - and will continue to do so as sexual selection is still occurring and we humans still find neotenic features attractive.

  13. Someone above commented regarding the AAT "On the surface, perhaps, but they don't stand up to scrutiny. Here is a critique."

     

    I'd just like to point out that the critique we are guided to is totally full of holes. It also contains loads stuff that sounds like it makes a point but doesn't, e.g.,

     

    "So contrary to the AAT claim, humans are not the only non-aquatic mammal which can hold its breath. Various monkeys, for instance, can and do hold their breath, and so do dogs. (Another common and related AAT claim is that non-aquatic animals have no control over their vocalizations, which should also surprise any dog owner.) "

     

    AAT says that apes cannot hold their breath. Apes are completely unable to hold their breath - even chimps cannot do this. Interestingly dolphins are unable to breath unconsiously. We are in between, being able to hold our breath and breath unconsiously.

     

    The only animal so far recorded able to utter human speech using the same mechanisms as a human (so birds don't count) was a sealion that had been kept in captivity. I have heard it speak and it sounds like a human - really wierd! It's ability is dependant on it being able to control its breath in a way only aquatic animals (and humans) are capable of.

     

    Without going on and on about the many innacuracies in this critique (its like reading one of those critiques on evolution by a believer in intelligent design!) I'll just say that one should be aware that many of the arguments presented are based on a false understanding of the AAT, and backed up by irrelevant scientific studies.

     

    AAT is going to be the new paradigm, so get on board!

  14. As Mokele has pointed out, sexual selection is still at work, and has probably been the major influence on human evolution for the last 2 million years. In order to cope with our environment we developed bigger brains by making big brains sexy! This programming (finding big brains sexy) is still at work. I should point out that we probably don't directly select for big brains, but focus on other more visible factors that correlate with having a big brain, such as neotenic features.

  15. Humans unlike all other apes have a liking for youthfulness. Thusly, in a million years we will all look like big skinny babies with massive heads. Cosmetic surgery may scupper this though and instead we'll look the same as we do now!

     

    We are still evolving - not due to our environment but due to our genetic programming - sexual evolution, if you will (re Red Queen etc).

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