(Illustration courtesy of Sabine Deviche)

What if survival of the fittest really was survival of the rich and powerful?

A new study by researchers at Arizona State University, the University of Cambridge and the Estonian Biocentre found a big drop in genetic diversity in the male lineage between 4,000 and 8,000 years ago; they did not find a similar drop among females.

Melissa Wilson Sayres is a Computational and Evolutionary Biologist at ASU, and a lead author of the study, which was published in an online issue of the journal “Genome Research.”