'Survival of the fittest' may take a back seat to wealth, power

Led by researchers from Arizona State University, geneticists have discovered a “bottleneck,” or decrease in genetic diversity in the male lineage about 4,000 to 8,000 years ago. This decrease may be related to the rise of agriculture, which means that wealthier men may have been fathering more children than their poorer counterparts.

In an article appearing in The Washington Post, reporter Danielle Paquette writes that the genetic bottleneck is the second that has been identified to date. The first occurred approximately 50,000 years ago, when there was a mass migration out of Africa.

School of Life Sciences assistant professor Melissa Wilson Sayres said researchers investigated the DNA samples from 456 men from seven regions around the world. The scientists focused particularly on the Y chromosome and the mitochondria. For every 17 women who reproduced, only one male passed on his DNA.

The research was originally published in the journal Genome Research.