Combining Calvin and Brace, your have the following theory:

Developing skills to:
* throw
* cook
and the resulting structural changes
were critical in our ultimate ability to speak.




http://www.med.jhu.edu/FAE/aapa/Paleoanthro.htm

 Locale and antiquity of cooking technology can account
 for the observed  differences in tooth size, and the locale and
 antiquity of projectile usage can be used to treat
 the appearance of post-cranial gracilization.

http://williamcalvin.com/bk2/bk2ch4.htm

http://www.beyondveg.com/billings-t/comp-anat/comp-anat-6b.shtml


Philip Thrift
http://www.paleofitness.com