Androgens in Human Evolution (brain evolution)
jamesmichaelhoward at my-deja.com jamesmichaelhoward at my-
deja.com Tue Apr 25 16:06:45 EST 2000 Androgens in Human
Evolution A New Explanation of Human Evolution James Michael
Howard Fayetteville, Arkansas, U.S.A. Human evolution consists
of chronological changes in gene regulation of a continuous and
relatively stable genome, activated by hormones, the production
of which are intermittently affected by endogenous and exogenous
forces. Periodic variations in the gonadal androgen,
testosterone, and the adrenal androgen, dehydroepiandrosterone
(DHEA), significantly participated in all hominid
transformations. The hominid characteristics of early
Australopithecines are primarily a result of increased
testosterone. The first significant cold of the early
Pleistocene resulted in an increase in DHEA that simultaneously
produced Homo and the robust Australopithecines. Subsequent
Pleistocene climatic changes and differential reproduction
produced changes in DHEA and tes