Re: Death of a hypothesis

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Karen (karen@uab.edu) wrote:
: HARRY R. ERWIN wrote:

: > The chin in modern man is a brace for the mandibular symphysis that
: > functionally replaces the superior and inferior tori found in hominoids
: > and hominids.

: What mandibular symphysis? Has h.s.s. not lost this morphological
: feature? Maybe I misunderstand your post but I thought that the
: mandibular symphysis was lost long ago.

The symphysis at the front of the lower jaw has been fused in advanced
primates for 20-30 MYr years, but it remains a point of weakness. Most
advanced primates have a superior or inferior transverse torus on the
inside of the mandible to brace the symphysis. Modern humans have
developed the chin--on the outside of the mandible--to perform that
function.

--

Harry Erwin, Internet: herwin@gmu.edu, Web Page: http://osf1.gmu.edu/~herwin 

49 year old PhD student in computational neuroscience ("how bats do it" 8)

and lecturer for CS 211 (data structures and advanced C++)

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