Brain Temperature Control & A. Africanus

Bill Weaver (
Sun, 20 Oct 1996 04:26:33 GMT

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.