Last weekend while my wife was out with our daughter-in-law, I got to go to
the Texas A&M library and browse a bit. I ran across an interesting book
about human evolution. The author's discussion of the neural anatomy of
Homo habilis, who lived about 2 million years ago is very interesting. He
believes it is likely that they could speak. If they could, then I would
contend that they are us.
Bradshaw states:
"If the evidence for speech in Neanderthals and Homo erectus from vocal
tract anatomy is equivocal, what conclusions can be drawn from the other
side of the coin, the central nervous system? It has been apparent for some
time that the skull of Homo habilis has gyral and sulcal impressions
similar to our own, and distinct from the pongids. There is a prominent
Broca's area in the posterior part of the inferior frontal convolution, and
a well-developed inferior parietal lobule, especially in the region of
Wernicke's area and the supramarginal and angular gyri-all major
speech-related regions involved in speech production and perception.
Lieberman comments that the apparent presence of such cortical structures
may not bear on the issue of speech, as subcortical structures, such as
basal ganglia and thalamus, would also have to be in place and clearly we
can tell little from skull impressions in that regard. Though this is of
course true, it is nevertheless anatomically unlikely that (surface)
cortical features would appear without the concomitant evolution of the
associated subcortical forebrain structures that transmit and modulate
ascending and descending information. Similarly, one can ask what, if Homo
habilis had the brain structures for language but not the vocal tract, was
the function of those brain structures? Is it likely that either system
would have evolved out of step with the other? It seems clear from both
sets of evidence, and from what we have already discussed, that though the
pygmy chimpanzee is capable of a level of comprehension of spoken speech
somewhere between that of a two or three year old, Homo habilis, whether or
not on our direct evolutionary trajectory, was likely to have been somewhat
further in advance. Comprehension of the level of a six year old, but still
without articulate speech of any kind? Somehow, the latter seems unlikely."
John L. Bradshaw, Human Evolution: A Neuropsychological Perspective,
(Psychology Press, 1997), p. 111
glenn
Foundation, Fall and Flood
Adam, Apes and Anthropology
http://www.flash.net/~mortongr/dmd.htm
Lots of information on creation/evolution
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