Robert van de Water wrote:
>>Doesn't really make any difference. Deacon writes:
Surprisingly enough, these studies show that the spatial
distribution of language functions vary from one person's
brain to another.
so more than just the handedness is variable from person to person and
extrapolating language functions from cranial endocasts is not certain.<<
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?
You wrote:
>>How many times have evolutionists done exactly this, I wonder? Seems
to me like the whole of "Artifact theory" is exactly this kind of an effort.
In this case, however, I think I am justified. We really do know very little
about brain function and you would have to be crazy to say otherwise. <<
That does not mean we know NOTHING!
You wrote:
>>That is exactly why I mentioned that modern man has a brain size that
varies by a factor of two. If our brains vary by that much and have the same
basic functions, then the brains of other primates might well exhibit the
same kind of behavior.<<
Actually, you would probably be surprised to learn that normally intelligent
people have brains smaller than those of a gorilla! I quote Science,
"'There's a young student at this university,' says Lorber, 'who has an IQ of
126, has gained a first-class honors degree in mathematics, and is socially
completely normal. And yet the boy has virtually no brain.' This student's
physician at the university noticed that the youth had a slightly larger than
normal head, and so referred him to Lorber, simply out of interest. 'When we
did a brain scan on him,' Lorber recalls, 'we saw that instead of the normal
4.5-centimeter thickness of brain tissue between the ventricals and the
cortical surface, there was just a thin layer of mantle measuring a
millimeter or so. His cranium is filled mainly with cerebrospinal
fluid."~Roger Lewin, "Is Your Brain Really Necessary," Science Dec. 12, 1980,
p. 1232.
Now, I just measured the size of my head. It is 23 inches in circumference
from front to back. Lets assume that that is a sphere and calculate this
fellows brain volume. (The sphere will over estimate the guys brain size
because the human skull is bread-loaf shaped The radius for a sphere of 23
inches circumference is 3.66 inches or 9.3 centimeters. Surface area of
such a sphere is 4 pi (9.3)^2=1086 square centimeters. A millimeter is .1
centimeter so his volume is 108.6 cubic centimeters of grey matter. Quite
impressive since this is an over estimate!
Let's see where this fellow fits on the evolutionary scale. Chimpanzees
have a 400 cc brain. (See C.L. Brace, Ashley Montague, "Man's Evolution, (New
Your MacMillan, 1965), p. 146
Jiminy, this guy must be a rhesus!
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.
You wrote:
>>Let's perform a Foleyesque thought experiment. Let's say there was a brain
region that is used in modern human beings for motor skills such as driving,
playing tennis or typing on the computer. If we found a similar structure in
homo habilis, would this mean that they had all of the advances of modern
technology? No one would argue that this was the case. Rather, they would
argue that the same structure was used for different purposes. So unless we
are prepared to believe that homo habilis had syntax and grammar, we should
conclude that these structures were used for something else. After all,
concluding that homo habilis had essentially modern language capabilities on
the basis of these cranial endocasts is stretching it just a little, don't
you think?<<
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.
glenn