I just sent this post, but I realized I had forgotten to include an extended
exerpt from Deacon. This is the same post except for that addition.
Glenn wrote:
>Why don't you give the citation with your quotation. It is considerate of
>others so they can go and examine your original source. Thanks.
>Secondly, what language functions is he talking about? Understanding?
>vocalizations? Motor control? As to language, I would like to quote Shreeve,
>"According to Ralph Holloway of Columbia University, the leading authority on
>ancient hominid brain structure, the markings revealing Broca's and
>Wernicke's areas appear millions of years before the Creative Explosion
>{upper paleolithic cultural revolution-grm} was allegedly triggered by the
>emergence of language, certainly by the time of *Homo habilis*. Holloway has
>also shown that *habilis* skulls reveal cerebral asymmetry: a left-hemisphere
>lopsidedness, which is associated in our species with language. More
>recently, Terry Deacon of Harvard University has pointed to language-related
>structures in the prefrontal cortex of the brain that also began to swell
>beginning with *Homo habilis*" James Shreeve, _The Neandertal Enigma_, 1995,
>p. 274-275. (a very, very good book)
>Are you sure that Deacon would agree with your position?
Evidently, Glenn needs to be reminded of my first post on this topic:
>Reading through the Cambridge Encyclopedia of Human
>Evolution (1992), I was interested to discover the following:
> The sulcal markings associated with Broca's language area (see
> main text) have recently been demonstrated in Homo habilis and
> H. erectus endocasts. These folds do not appear on endocasts
> of australopithecine brains. Does this mean that Broca's area
> first appeared in the brains of early homo? Yes, if we define
> it only in morphological terms. But if we are interested in the
> language functions of Broca's area, the endocast evidence is
> less compelling for several reasons. There is variability in the
> presence and the position of these sulci in human brains and some
> inconsistency in the correspondence of the landmarks with the
> locations of language functions. More importantly, an homologous
> area has been demonstrated in monkey brains, so the appearance of
> these gyri and sulci in fossils does not indicate the appearance
> of a totally new structure (p. 117)
** Addition**>
> Finally, the increase in brain size between australopithecines
> and early Homo increased the number of folds in all parts of
> of the cerebral cortex. These new folds may simply be an
> effect of this overall size increase rather than a specific
> change. These hominids may have been the first to use Broca's
> area for language, but endocasts alone are not enough to prove
> it. (P.117)
The above was written by Deacon, so he does agree with me that these
endocasts are not enough evidence to deduce language function.
How interesting that Deacon is cited by Shreeve:
>More
>recently, Terry Deacon of Harvard University has pointed to language-related
>structures in the prefrontal cortex of the brain that also began to swell
>beginning with *Homo habilis*" James Shreeve, _The Neandertal Enigma_, 1995,
>p. 274-275.
Glenn continues:
>The point is that what is important is not size but organization of the
>brain. Your position might be correct that the fossil men are not human, but
>you can not rule out the possibility that their brains were organized more
>efficiently than ours and so were capable of some of the functions we
>possess.
My original point was that size was a weak argument. Thank you for confirming
this point.
Glenn concludes:
>I would suggest that your logic is flawed here. The American Indians of 1500
>BC have the same cranial structures and size as everyone else. They did
>not have the advances of modern technology, but they were capable of
>inventing and building said technology. Besides there is no brain region
>associated with Tennis so your question is meaningless. There are brain
>regions associated with language. Face up to that fact or rewrite all the
>encyclopedias.
I believe that there are brain areas associated with language, but where
they are varies from person to person according to Terence Deacon. To be
able to discuss this topic more thoroughly, I would have to do a great deal
of research and I simply don't have the time. Contact Deacon and if he
agrees that these endocasts are conclusive evidence of syntax and grammar
among homo habilis, I will yield the point.
In Christ
robert van de water
associate researcher
UCLA