CRANOFACIAL FEMINIZATION, SOCIAL TOLERANCE AND THE ORIGINS OF BEHAVIORAL MODERNITY

Published by the University of Chicago express in Current Anthropology
August, 2014 

LESS TESTOSTERONE, MORE TOLERANCE.

Modern Humans show reduction in average brow ridge projection and shortening of the upper facial skeleton compare to the first Homo sapiens. Generally, both features reflect a reduction in the testosterone action. 

A reduction in testosterone levels was determinant for the arising of the civilization. This is what a team of biologist and anthropologist suggest in their study considering  1400 ancient and modern craniums.

The Modern Human beings appeared in the fossil register 200 million years ago. But it wasn´t until 50 million years ago when our ancestors started creating art and advanced tools. It is argue that the florishing of the culture and the improvement in social tolerance is due to temporal changes in human craniofacial morphology. Indeed, this reflects reductions in average androgen reactivity (lower levels of adult circulating testosterone or reduced androgen receptor densities).

If you want a more digitalized version, enjoy this video: 

http://www.sciencedaily.com/videos/c33f3ee637647d66c2f620c3bab47948.htm

For futher information: 
http://www.jstor.org/discover/10.1086/677209?uid=3737952&uid=2&uid=4&sid=21104176632341