Sexual Competition Drives Evolution Of A Sex-Related Gene

In what could be termed a truly seminal discovery, researchers have shown that when females are more promiscuous, males have to work harder — at the genetic level, that is. More specifically, they determined that a protein controlling semen viscosity evolves more rapidly in primate species with promiscuous females than in monogamous species. The finding demonstrates that sexual competition among males is evident at the molecular level, as well as at behavioral and physiological levels. The researchers, led by Howard Hughes Medical Institute investigator Bruce Lahn at the University of Chicago, published their findings in the November 7, 2004, issue of Nature Genetics.