jackson@ttidca.TTI.COM (Dick Jackson) (08/04/87)
This is a question which has intrigued me for a long time, I wonder if anyone has any thoughts? Assume that humans have succeeded in evolutionary terms by exploiting the "niche" of intelligence, i.e. being capable of rational planning. Assume that homo sap evolved gradually from some pre-homo with only apelike reasoning powers. Also I have to remember that this growth of "intelligence" didn't just happen, there was environmental pressure driving it, i.e. at some point it became an evolutionary advantage to be a little bit smarter than your peers, you survived preferentially to have more children who inherited your smartness, and so on. I can see how this would work at the beginning of the process; development of an ability to construct mental models of the world allowed prey to be outwitted instead of outpowered. Language allowed group planning for mutual benefits, better shelter, shared gathering and storing of food,etc. But then I look a modern human, playing baseball, or playing the piano, or making abstruse mathematical "discoveries". It seems to me that we are much too mentally able than we need to be. What was the environmental pressure that made us THIS smart? And, why not smarter? One theory that has been put forward is that, at some stage, our ancestors were not the only species specializing in being bright, and the two rival species "fought it out", each pushing the other to be cleverer. Finally, WE WON and wiped out the other (Neanderthal?). OK, I can't get too excited about this theory, but at least its a try. There is another answer which is dissatisfying, i.e. that we are this smart because we are capable of posing this question. If less smart we couldn't have thought of it, if more smart -- the answer would be obvious. Dick Jackson
werner@aecom.YU.EDU (Craig Werner) (08/05/87)
In article <1041@ttidca.TTI.COM>, jackson@ttidca.TTI.COM (Dick Jackson) writes: > > It seems to me that we > are much too mentally able than we need to be. What was the environmental > pressure that made us THIS smart? This is a question whose answers are bound to be unsatisfying. However, the phrasing reveals a common misconception of evolution, that it in fact has a reason for everything. The pressures of evolution are mostly negative. Unfavorable traits are weeded out, even if their status as "unfavorable" are only relative to a changing environment, or "superior" competitors. There is very little positive selection. An answer closer to the original spirit of the question would go as follows: the various parts of the brain utilize very similar mechanisms of synaptic transmission and selection in the visual cortex and speech centers (clearly advantageous) probably brought other areas (whose growth was only selected against by the fact that the total cranial size had to be, on the average, smaller than a female pelvis). There is a far more compelling reason. It is now generally forgotten that diseases such as Measles, Smallpox, Rubella, Mumps, Cytomegalovirus, Herpes, etc., can and do infect the brain with neuronal destruction, generally during childhood. Since selection only occurs on the reproductive population, that means that selection of brain size generally occurred on a population whose neuronal complement had been ravaged by disease. Disease, I might add, that generally does not exist in the developed world today. This would then give the appearance of "redundant" neurons, which are available for higher functions, in the absence of such disease. Then, there is just the matter of projection. Most of the acheivements of mankind that are remembered are performed by the top few percent of talented persons in that respective area. The unconscious extrapolation generalizing back can account for most of the bewilderment. -- Craig Werner (future MD/PhD, 3 years down, 4 to go) werner@aecom.YU.EDU -- Albert Einstein College of Medicine (1935-14E Eastchester Rd., Bronx NY 10461, 212-931-2517) "Meiguanxi ye meibanfa"
heather@blia.BLI.COM (Heather Mackinnon) (08/06/87)
In article <1253@aecom.YU.EDU>, werner@aecom.YU.EDU (Craig Werner) writes: > > However, the phrasing reveals a common misconception of evolution, > that it in fact has a reason for everything. The pressures of evolution > are mostly negative. Unfavorable traits are weeded out, even if their > status as "unfavorable" are only relative to a changing environment, or > "superior" competitors. There is very little positive selection. I have to disagree with this! Another way of saying that unfavorable traits are weeded out is to say that favorable traits succeed. A tiger with claws will succeed over a tiger with no claws. You can either say that the claws are selected for or clawlessness is selected against. If claws were useless to tigers, they probably wouldn't have them since the energy required to grow and maintain claws wouldn't give the tiger any advantage. If a strain of animal develops a trait that makes it compete more effectively, that trait will be selected for just as surely as a negative trait will be selected against. The primary competition in the human evolutionary niche is from other humans. Humans use their brains to compete with one another for resources. Clever, dextrous humans are more successful in human endeavors than dull, clumsy ones. Our cleverness was necessary earlier in human evolution to compete against large predators, kill game, and survive through the ice age. It's also possible that evolution is preprogrammed to some extent, like the flowering of a plant. At which point our cleverness could be a growing towards an end we can only dimly envision. Heather Mackinnon Just an avid amateur
mcguire@aero.ARPA (Rod McGuire) (08/07/87)
In article <1041@ttidca.TTI.COM> jackson@ttidcc.UUCP (Dick Jackson) writes: >Assume that humans have succeeded in evolutionary terms by exploiting the >"niche" of intelligence .... >One theory that has been put forward is that, at some stage, our ancestors >were not the only species specializing in being bright, and the two rival >species "fought it out", each pushing the other to be cleverer. Finally, >WE WON and wiped out the other (Neanderthal?). OK, I can't get too >excited about this theory, but at least its a try. Why assume that selection for intelligence was through competition between homo and some other specie(s). When homo gene pools can be reproductively isolated (as is almost the case for tribes, nations, and races) they can fight out the genes among themselves.
beede@hubcap.UUCP (Mike Beede) (08/08/87)
in article <3058@blia.BLI.COM>, heather@blia.BLI.COM (Heather Mackinnon) says: > > [ much deleted ] > > It's also possible that evolution is preprogrammed to some extent, like > the flowering of a plant. At which point our cleverness could be a > growing towards an end we can only dimly envision. > A lovely thought, but ``destructive to the logical faculty.'' If we allow magical explainations, we lose the incentive to understand what really happened. There is absolutely no evidence (that I am aware of :->) that there is a mechanism underlying evolution that is directing it in some particular direction. Indeed, looking at all the false starts that good old Parent Nature (the ERA version of Mother Nature) made is very convincing. BTW, for those interested in evolution and related stuff, but who are not professionals (as I am not), Stephen J Gould's new book, _The Flamingo's Smile_, is very good (as were the earlier ones in the series). -- Mike Beede Computer Science Dept. UUCP: . . . !hubcap!beede Clemson University INET: beede@hubcap.clemson.edu Clemson SC 29634-1906 YOUR DIME: (803)656-{2845,3444}
jru@etn-rad.UUCP (John Unekis) (08/10/87)
In article <373@hubcap.UUCP> beede@hubcap.UUCP (Mike Beede) writes: >in article <3058@blia.BLI.COM>, heather@blia.BLI.COM (Heather Mackinnon) says: >> It's also possible that evolution is preprogrammed to some extent, like >> the flowering of a plant. At which point our cleverness could be a >> growing towards an end we can only dimly envision. >> >A lovely thought, but ``destructive to the logical faculty.'' If we >allow magical explainations, we lose the incentive to understand what >really happened. There is absolutely no evidence (that I am aware of :->) >that there is a mechanism underlying evolution that is directing it in >some particular direction. Indeed, looking at all the false starts ..... As someone whose familiarity with the mechanics of evolution has been gained through the popular press I have what may seem to some to be a rather naive question, but here it is anyway. What if the the real advantage of sexual versus asexual reproduction was that it allowed the genes of the species to contain some kind of checkpoint sequence. The mechanism would essentially function to check how often gene sequences were 'seen together'. In a large population, one would expect that in-breeding would be kept to a minimum, and the mechanism would remain dormant. If external pressures began to reduce the population, the checkpoint sequences would begin to recognize each other more often, and would trigger changes to the genetic sequence when they did. Most of these changes would be self-destructive, but some might produce succesful adaptations for dealing with the forces which were threatening the population. Obviously this mechanism would have had to come into being at random. But once it developed, it would allow for a 'punctuated equilibrium', where a succesful species would change very little, but a species that was threatened would change rapidly in an attempt to cope with outside pressures. The mechanism would hardly be foolproof, and many species would still become extinct. My question is, is this a feasable scenario? --------------------------------------------------------------- ihnp4!wlbr!etn-rad!jru
beede@hubcap.UUCP (08/11/87)
in article <243@etn-rad.UUCP>, jru@etn-rad.UUCP (John Unekis) says:
]
] What if the the real advantage of sexual versus asexual reproduction
] was that it allowed the genes of the species to contain some kind of
] checkpoint sequence. The mechanism would essentially function to check
] how often gene sequences were 'seen together'. In a large population,
] one would expect that in-breeding would be kept to a minimum, and the
] mechanism would remain dormant. If external pressures began to reduce
] the population, the checkpoint sequences would begin to recognize each
] other more often, and would trigger changes to the genetic sequence when
] they did. Most of these changes would be self-destructive, but some might
] produce succesful adaptations for dealing with the forces which were
] threatening the population.
]
This is a very interesting idea. I believe that many species typically
interbreed to a large extent, and certainly there are strains of lab
animals that are inbred to a degree where someone would have noticed a
huge mutation rate. But then again . . .
But, what do I know about it? At any rate, keep in mind that not too many
changes are needed to produce a new species over an instant of geologic
time (say 10,000 years . . .). What little I do know suggests that a tiny
change to some regulator (or meta-regulator, or meta-meta- . . .) sequence
can have a huge impact on an organism. An accelerated production of
variation may not be needed.
Still a great idea -- stranger things exist. What does evolutionary theory
suggest about it? How 'bout it all you biology dudes?
--
Mike Beede
Computer Science Dept. UUCP: . . . !hubcap!beede
Clemson University INET: beede@hubcap.clemson.edu
Clemson SC 29634-1906 YOUR DIME: (803)656-{2845,3444}
coray@nucsrl.UUCP (Elizabeth) (08/12/87)
>>What was the environmental pressure that made us THIS smart? And, why not >>smarter? >>One theory that has been put forward is that, at some stage, our ancestors >>were not the only species specializing in being bright, and the two rival >>species "fought it out", each pushing the other to be cleverer. Finally, >>WE WON... You got it. It was the war between the sexes that did it, and women lost. That's why we're so short... and you're so dumb. M. Elizabeth Corey (soon to be extinct)
msellers@mntgfx.MENTOR.COM (Mike Sellers) (08/12/87)
In article <376@hubcap.UUCP>, beede@hubcap.UUCP (Mike Beede) writes: > in article <243@etn-rad.UUCP>, jru@etn-rad.UUCP (John Unekis) says: > ] > ] What if the the real advantage of sexual versus asexual reproduction > ] was that it allowed the genes of the species to contain some kind of > ] checkpoint sequence. The mechanism would essentially function to check > ] how often gene sequences were 'seen together'. In a large population, > ] one would expect that in-breeding would be kept to a minimum, and the > ] mechanism would remain dormant. If external pressures began to reduce > ] the population, the checkpoint sequences would begin to recognize each > ] other more often, and would trigger changes to the genetic sequence when > ] they did. Most of these changes would be self-destructive, but some might > ] produce succesful adaptations for dealing with the forces which were > ] threatening the population. > ] > > ...a great idea -- stranger things exist. What does evolutionary theory > suggest about it? How 'bout it all you biology dudes? > -- > Mike Beede A couple of heuristics applicable to ideas like this one: 1) Does it imply or require design? If it does, then it isn't a very good candidate. 2) Does it "buy" the gene, organism, or species anything? If it doesn't help one of these directly (and species can reduce to organism which ulimately reduces to gene), it probably isn't a good idea either. From what I can see, this idea passes both of these heuristics. There are known genetic conditions that only express themselves when other specific genes are present (such as six-fingeredness, which is dominant (!) but only, I believe, under certain circumstances), or absent (such as hemophilia). Such a check-function as described above is quite an interesting idea, though like many in evolutionary thought, probably not easily testable. [WARNING: bizarre idea surfacing... serious readers hit 'n' while you can!] WHAT IF... life here *was* seeded from elsewhere (Slaver carbon-based food yeasts gone awry, ala Niven?) but within each simple proto-viral RNA/DNA complex, a little piece of the genetics that would make a sentient race was placed (aaagh -- by design, of course). Over the course of maaany years, these pieces recognized each other (by having receptor sites for compatible proteins made by others of these genetic pieces), and grouped themselves together using a recognize-and-build variant of the check function mentioned above. Could all other terrestrial life forms then simply be supports and buttresses leading to the pinnacle that is humanity? Or, more interestingly, could we simply be the platform from which the *truly* sentient being (the one intended all along) will spring? Hmmm. Okay, okay, back to sci.bio.
lonetto@phri.UUCP (Michael Lonetto) (08/13/87)
In article <1041@ttidca.TTI.COM> jackson@ttidcc.UUCP (Dick Jackson) writes: >I can see how this would work at the beginning of the process; development >of an ability to construct mental models of the world allowed prey to be >outwitted instead of outpowered. Language allowed group planning for >mutual benefits, better shelter, shared gathering and storing of food,etc. (So far little that chimpanzees can't do) >But then I look a modern human, playing baseball, or playing the piano, >or making abstruse mathematical "discoveries". It seems to me that we >are much too mentally able than we need to be. What was the environmental >pressure that made us THIS smart? And, why not smarter? > But then I look at many modern humans watching Dynasty, at a total loss for how to cope, idealizing Ollie North (and even BELIEVING him), poisoning the water and atmosphere, arguing that "there's plenty of room for more people" (though aparently there isn't enough room for the rest of the species on this planet) and it seems that the larger part of the question is indeed "why not smarter?" It would seem that once intelligence and society had reached a certain point, social change took over the evolutionary burden. It seems to me that you're looking at a small minority of humanity who might be capable of contributing to the further evolution of this society. The rest are just along for the ride. Looking around at all the people out on the street here (New York), it seems they're starting to fall off the wagon. -- Michael Lonetto UUCP:(allegra!phri!lonetto) USMAIL: Public Health Research Institute, 455 1st Ave, NY, NY 10016
rgalek@gouldsd.UUCP (Richard G Aleksandr) (08/13/87)
In article <1041@ttidca.TTI.COM>, jackson@ttidca.TTI.COM (Dick Jackson) writes: > This is a question which has intrigued me for a long time, I wonder if > anyone has any thoughts? > > ........ I look a modern human, playing baseball, or playing the piano, > or making abstruse mathematical "discoveries". It seems to me that we > are much too mentally able than we need to be. What was the environmental > pressure that made us THIS smart? And, why not smarter? > > Dick Jackson I have a different view on this than the physiological and evolutionary explanations given so far. First, there is no proof or strong evidence which I am aware of which makes "smartness" totally a physiological or evolutionary function. Second, it seems to me that after a rudimentary intelligence is developed to the point that one can start to ask questions about his/her environment, that this would naturally lead to curiosity in some people to find out more. I disagree with your assumption that we are so much smarter than our ancestors; isn't it possible that we just have a lot more information, as opposed to raw intelligence. And this information has not been garnered, in my opinion, in response to environmental pressure as much as simple curiosity. Richard Aleksandr
jru@etn-rad.UUCP (John Unekis) (08/13/87)
In article <2842@phri.UUCP> lonetto@phri.UUCP (Michael Lonetto) writes: >But then I look at many modern humans watching Dynasty, at a total >loss for how to cope, idealizing Ollie North (and even BELIEVING him), >... >It seems to me that you're looking at a small minority of humanity who >might be capable of contributing to the further evolution of this >society. The rest are just along for the ride. Looking around at all >the people out on the street here (New York), it seems they're starting >to fall off the wagon. ... Unfortunately the persons whom we would most like to see contributing to our gene pool won't take the time to do so. Intelligent people in our society tend to choose fast-lane lifestyles that leave no room for having or raising children. The birth rate in this country goes up dramatically as IQ goes down, making intelligence a negative factor in survival. People wonder why SAT scores keep falling and illiteracy rates keep climbing. It is clearly because as a race we are slipping into a miasma of dull-witted servile stupidity. This is why free abortions are such a good idea , they are predominantly used by the poor and those to stupid to figure out how to make use of a condom. But suppressing the birth rates of the miscegenated morons won't do the whole trick. Those of us who possess superior intelligence have a moral imperative to pass on our genes for the good of the race. So why don't we round up all the females of suitable intelligence and start breeding farms where we can create the kernal of a select group who will save humanity by seizing power and eliminating all the undesireables. Mine Fuhrer, I can walk! Seig Heil (oops) Lyndon Larouche for President ------------------------------------------------------------------ It's a joke, really, no .. stop ... not the cattle prod! ihnp4!wlbr!etn-rad!jru
lewando@phri.UUCP (Mark Lewandoski) (08/16/87)
In article <1041@ttidca.TTI.COM>, jackson@ttidca.TTI.COM (Dick Jackson) writes: > This is a question which has intrigued me for a long time, I wonder if > anyone has any thoughts? > > Assume that humans have succeeded in evolutionary terms by exploiting the > "niche" of intelligence, i.e. being capable of rational planning. Assume > that homo sap evolved gradually from some pre-homo with only apelike > reasoning powers. > > Also I have to remember that this growth of "intelligence" didn't just > happen, there was environmental pressure driving it, i.e. at some point it > became an evolutionary advantage to be a little bit smarter than your > peers, you survived preferentially to have more children who inherited > your smartness, and so on. Thanks for the thoughtful question. I suggest a book for you called _The Interpretation of Culture_ by Clifford Geertz. He is a very thought-provoking, talented anthropologist and writer. In the book's first chapter he runs this argument which addresses your question, _somewhat_... What is basic human nature (under the overlay of a paerticular culture)? Many schools of thought have proposed different answer to this: noble savage or savage killer. And over this basic core of human nature is our culture: American, Iranian, Yanamato or whatever... Then he looks at the fossil record and it shows that culture began _before_ the modern human brain developed. By culture, we mean the use of language and symbols to make meaning of the world and to pass on information. The evidence of culture is carving, paintings, symbols, remnants of burial ceremonies, etc. OK, so this occurs and then sometime afterwards (I read this a while ago) the modern human brain development... (based on skulls found...ie our protohuman ancestors had rudiments of culture and language). SO this pivot of his thesis is this: the ability to use culture (ie useful information passed on in symbols, signs and signals) was a selective force in the evolution of the human brain and nervous system. Those creatures that were better able to use the growing culture-bound\ information, because they were born brains better suited to this, had a selective advantage...Until we get the modern brain which _requires_ cultural information to function. So the original question: what is the basic human nature under the superficial overlay of our particular culture? is a meaningless question: the basic human nature is to have a nervous system which requires a particular culture to function. Strip away that culture amd you have a nonworking monstrosity. (I dont mean "function" in the physiological sense, I mean without culture there is no thinking, intelligence and emotion) I think this has some bearing on your question vis a vis the evolution of human intelligence. In order to evolve such interlligence in intergrated with the development of culture. And culture, while limited by biology because it's units are persons, is not a genetical controlled phenomena, like the ability to split a certain sugar or grow wings on certain parts of the body. Hope this helps. Mark Lewandoski
jc@minya.UUCP (John Chambers) (08/16/87)
> > in article <243@etn-rad.UUCP>, jru@etn-rad.UUCP (John Unekis) says: > > ] > > ] What if the the real advantage of sexual versus asexual reproduction > > ] was that it allowed the genes of the species to contain some kind of > > ] checkpoint sequence. The mechanism would essentially function to check > > ] how often gene sequences were 'seen together'. In a large population, > > ] one would expect that in-breeding would be kept to a minimum, and the > > ] mechanism would remain dormant. You might expect that, but you'd be wrong. Contrary to popular thought, Ma Nature (aka The Evolutionary Process) doesn't minimize inbreeding. On the contrary, a small (but non-zero) level of inbreeding is sufficiently adaptive that most species have ways of maintaining it above the expected level of random interbreeding. Investigate the literature on the meaning and function of the term "deme". The adaptive advantages of low levels of inbreeding can be explained fairly simply: it is the easiest way to bring outrecessive genes so they can be selected for/against. -- John Chambers <{adelie,ima,maynard}!minya!{jc,root}> (617/484-6393)
kent@xanth.UUCP (Kent Paul Dolan) (08/19/87)
In article <2851@phri.UUCP> lewando@phri.UUCP (Mark Lewandoski) writes: >In article <1041@ttidca.TTI.COM>, jackson@ttidca.TTI.COM (Dick Jackson) writes: >> [question bearing on the effect of culture on intelligence omitted] > [answer noting that culture _preceeds_ our present level of intelligence > omitted, except for:] >SO this pivot of his thesis is this: the ability to use culture (ie >useful information passed on in symbols, signs and signals) was a >selective force in the evolution of the human brain and nervous system. Independent of this discussion, this question came to mind a couple of weeks ago, in response to a comment by a new Chinese (girl)friend I've met. It may be apropos of nothing at all, but it helps me answer the mystery of why the Chinese graduate students corner the market on A's in computer science. ;-) We were looking at a picture she had of a Chinese actress, and she mentioned that the woman was unattractive because "her forehead looks narrow" (the picture showed a young woman, in costume, with her hair combed down so that it left only an inverted "v" of forehead showing.) We continued the discussion for clarification, and she finally gave me to understand that her (_the_ ?) Chinese ideal of beauty includes a wide, clear forehead. The question that came instantly to my mind (but not lips, I'm _trying_ to make a good impression on this rather desireable young woman) was: wouldn't self selection for high, clear foreheads, i.e., probably enlarged cranial capacity, be an excellent way to bias toward the reproduction of the more intelligent members of a race/species? It seems that there is every chance that a standard of "(s)he is successful, therefore attractive, therefore beautiful, therefore desireable as a mate", spread through a culture which could amplify and maintain it, would fairly rapidly select for the outward manifestation of increased intelligence (typically, in human evolution, high foreheads). Is this a reasonable explanatory mechanism for the rapid development not only of enough intelligence to give us the edge in interspecies competition, but also overshoot to an entirely unnecessary capability for deeply abstract reasoning? I compare to the cultures whose fertility goddesses all had exceptionally wide hips. If this became the standard of beauty, the culture would self select for easier childbirth, and therefore out compete the next tribe down the valley in terms of successful reproduction. Again, this requires a culture of artifacts and shared ideas to perpetuate _quickly_, although peacocks, for example, show that a standard of attractiveness can be eventually selected by non-cultural evolution also. Comments welcome. I claim _no_ expertise in biology, bits and bytes are my game, so you probably won't hurt my feelings much even with a flame. (Flames about racist/sexist artifacts of this article are unwelcome; I know what I said, and I just used the examples that came readily to hand. Nothing derogatory intended.) Kent, the man from xanth.
jnp@calmasd.GE.COM (John Pantone) (08/22/87)
In article <2172@xanth.UUCP>, kent@xanth.UUCP (Kent Paul Dolan) writes: > We continued the discussion for clarification, and she finally gave me > to understand that her (_the_ ?) Chinese ideal of beauty includes a > wide, clear forehead. > > The question that came instantly to my mind (but not lips, I'm > _trying_ to make a good impression on this rather desireable young > woman) was: wouldn't self selection for high, clear foreheads, i.e., > probably enlarged cranial capacity, be an excellent way to bias toward > the reproduction of the more intelligent members of a race/species? Only one problem, Kent. High, clear foreheads don't indicate (necessarily) a large cranial capacity (could have a small hind-head) nor does large cranial capacity indicate high intelligence. Some species of Dolphin, almost all whales and elephants have brains physically larger than ours - yet it is not true that they have greater intelligence. The "classic" anecdote on this subject is the one regarding the largest brain (human) recorded - which belonged to a mentally deficient man. I would suspect that fashions, which concern themselves with superficial configurations, would only very rarely affect substantive things like basic intellegence, etc. More ideas netters? -- These opinions are solely mine and in no way reflect those of my employer. John M. Pantone @ GE/Calma R&D, Data Management Group, San Diego ...{ucbvax|decvax}!sdcsvax!calmasd!jnp jnp@calmasd.GE.COM
rcopm@koel.rmit.oz (Paul Menon) (08/26/87)
John M. Pantone writes... > a large cranial capacity (could have a small hind-head) nor does large > cranial capacity indicate high intelligence. Some species of Dolphin, > almost all whales and elephants have brains physically larger than ours - > yet it is not true that they have greater intelligence. sez who? Paul Menon. Dept of Communication & Electronic Engineering, Royal Melbourne Institute of Technology, 124 Latrobe St, Melbourne, 3000, Australia ACSnet: rcopm@koel UUCP: ...!seismo!munnari!koel.rmit.oz!rcopm CSNET: rcopm@koel.rmit.oz ARPA: rcopm%koel.rmit.oz@seismo BITNET: rcopm%koel.rmit.oz@CSNET-RELAY PHONE: +61 3 660 2619.
peter@sugar.UUCP (08/30/87)
In article <2346@calmasd.GE.COM>, jnp@calmasd.GE.COM (John Pantone) writes: > In article <2172@xanth.UUCP>, kent@xanth.UUCP (Kent Paul Dolan) writes: > > Chinese ideal of beauty includes a wide, clear forehead. > > > > woman) was: wouldn't self selection for high, clear foreheads, i.e., > > probably enlarged cranial capacity, be an excellent way to bias toward > > the reproduction of the more intelligent members of a race/species? > > Only one problem, Kent. High, clear foreheads don't indicate (necessarily) > a large cranial capacity (could have a small hind-head) nor does large But there's no corresponding selection for any features that decrease cranial capacity. > cranial capacity indicate high intelligence. Some species of Dolphin, > almost all whales and elephants have brains physically larger than ours - > yet it is not true that they have greater intelligence. Firstly, it's not known whether they have greater intelligence or not. you could state "it's not known that they have greater intelligence", or "but this doesn't imply they have greater intelligence". Measuring the intelligence of a non tool-user is hard. Secondly, we're not talking about dolphins or elephants here, but humans. > The "classic" anecdote on this subject is the one regarding the largest > brain (human) recorded - which belonged to a mentally deficient man. Of course, one sample point is statistically significant (sarcasm). -- -- Peter da Silva `-_-' ...!seismo!soma!uhnix1!sugar!peter -- U <--- not a copyrighted cartoon :->
palmer@tybalt.caltech.edu.UUCP (08/31/87)
In article <2346@calmasd.GE.COM> jnp@calmasd.GE.COM (John Pantone) writes: >Only one problem, Kent. High, clear foreheads don't indicate (necessarily) >a large cranial capacity (could have a small hind-head) nor does large >cranial capacity indicate high intelligence. Some species of Dolphin, >almost all whales and elephants have brains physically larger than ours - >yet it is not true that they have greater intelligence. > >The "classic" anecdote on this subject is the one regarding the largest >brain (human) recorded - which belonged to a mentally deficient man. There are also poeple with hollow brains, hydrocephalics whose brain is just a thin veneer over a bubble of cerebro-spinal fluid. Many of these people are normal or above normal in intelligence, even though they have only 5% (!!!) of the normal brain mass. Are there any theories out there about why the rest of us need so much brain when these people get by with so little? is it just because of the advantages that redundancy gives us? David Palmer palmer@tybalt.caltech.edu ...rutgers!cit-vax!tybalt.caltech.edu!palmer The opinions expressed are those of an 8000 year old Atlantuan priestess named Mrla, and not necessarily those of her channel.
beede@hubcap.UUCP (09/01/87)
in article <3835@cit-vax.Caltech.Edu>, palmer@tybalt.caltech.edu (David Palmer) says: > > There are also poeple with hollow brains, hydrocephalics whose brain is > just a thin veneer over a bubble of cerebro-spinal fluid. Many of these > people are normal or above normal in intelligence, even though they have > only 5% (!!!) of the normal brain mass. I have seen mention of this before, but never in what I would call a reliable source. If you (or any other netian) could offer some citation for this, I'd appreciate it. Not criticising, just interested. P.S., mail would be nice -- I'll be gone for 2 weeks and responses will probably expire before I see them. -- Mike Beede Computer Science Dept. UUCP: . . . !hubcap!beede Clemson University INET: beede@hubcap.clemson.edu Clemson SC 29634-1906 YOUR DIME: (803)656-{2845,3444}