Biologists turn back the clock to understand evolution of sex differences

Battles of sexes shown to spur adaptive sex differences For video and explanations Sex differences account for some of the most spectacular traits in nature: the wild colours of male guppies, the plumage of peacocks, tusks on walruses and antlers on moose. Sexual conflict - the battle between males and females over mating - is thought to be a particularly potent force in driving the evolution traits that differ in males and females. However, the genetic processes responsible for producing such traits are not well understood, nor how they evolved from their simpler less elaborate ancestral forms. We tend to assume that each tiny step in evolution is an advantage. But are they really? To investigate, a research team led by Locke Rowe of the Department of Ecology and Evolutionary Biology at the University of Toronto with collaborators Ehab Abouheif of the Biology Department at McGill University, and Abderrahman Khila of Toronto and McGill, found a way to recreate those incremental steps, turning back the evolutionary clock and watching the transformation of simple antennae into more elaborate ones. The antennae are used to grasp females during mating interactions, and the researchers were able to measure their increasing utility in this new function as they were increasingly elaborated. The study entitled "Function, developmental genetics, and fitness consequences of a sexually antagonistic trait" is being published in Science May 4.