Re: Brain Temperature Control & A. Africanus
Doug McKean (doug_mckean@paragon-networks.com)
Thu, 24 Oct 1996 13:18:21 -0400
Bill Weaver wrote:
>
> I recently caught a documentary that addressed an interesting idea
> relating to the origins of human intelligence. It started with the
> idea that man's upright posture was mainly a solution to a thermal
> problem sparked by an abrupt change in climate. However, once the
> upright posture was attained and the thermal circulatory systems that
> regulate brain temperature adapted to this new posture (which can be
> seen from brain casts to have occurred between A. Afarensis and later
> gracile australopithecines such as Africanus) the side effect of this
> adaptation was that larger brain sizes could now be supported because
> they could be cooled.
>
> Does anybody know of a good article addressing the impact of these
> findings regarding the re-routing of the brain's circulatory system,
> which appears to connect A. Africanus quite directly with us? The
> evidence for and against the role of Africanus in our direct ancestry
> was not discussed in detail.
As you may well already know, you are referring to
"encephalisation in australopithecines" which has two things to consider:
1. The development of an increased cooling system necessary
for the sensitive intra-cranial nervous system was the driving
factor for increased brain sizes.
Commonly known as the "radiator theory".
2. Diet may well have been a serious factor in the development of
of the cooling system for the brain.
A Dr. Peter Wheeler gave a presentation at Cornell on this
specific topic sponsered by the Dept of Psychology.
Perhaps you could contact them.
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Doug McKean
doug_mckean@paragon-networks.com
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The comments and opinions stated herein are mine alone,
and do not reflect those of my employer.
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