23 September 2002

Studying the sex life of a fly species native to Australia’s east coast rainforests could explain why females get more of a “buzz” from some males than others.

“Theory suggests that females prefer extreme male traits because they may indicate that those males carry genes that confer high fitness to offspring. These genetic principles apply to mate choice in all species, including humans,” said Dr Mark Blows from The University of Queensland`s School of Life Sciences.

Dr Blows has received $52,000 as one of seven recipients of the 2002 UQ Foundation Research Excellence Awards for early career researchers, valued in total at nearly $500,000.

The annual awards, now in their fourth year, recognise outstanding performance and leadership potential, and this year formed part of the inaugural UQ Research Week from Monday, September 23–Friday, September 27.

His work for the first time brings some key aspects of sexual selection together in one genetic experiment.

“We have already shown that female choice affects offspring fitness in a genetic experimental design that allowed us to estimate the genetic associations between female preference, male attractiveness and offspring fitness,” Dr Blows said.

“The genes for female preference have become associated with genes that confer high offspring fitness. This suggests that females have gained good genes for their past offspring by making a choice between males.”

The Drosophilia serrata fly that Dr Blows will use to undertake his research has two outstanding credentials for the task.

Number one is that Dr Blows and colleagues have determined that the concentration of the cuticular hydrocarbons (CHCs) in a pheromone “signal” issued by males dictates their appeal to females.

Secondly, the two-week lifespan of the fly between egg and sexual maturity allows genetic experiments to be conducted quickly across many generations.

A two-generation experiment already conducted by Dr Blows in the laboratory has produced some ego-damaging news for male Drosophilia serrata, and sobering cause for reflection for the females who can’t resist macho archetypes.

“The problem for males is that producing such attractive CHCs is energetically expensive,” he said.

“The females want attractive males because attractiveness may have indicated that a male carried genes for high offspring fitness in the past, but now the genes carried by attractive males aren’t very good because of all the effort of signaling.

“That means the genes that make a male attractive, at the same time confer lower offspring fitness. It eventually leads to a balance between sexual and natural selection, as females still choose attractive males, but very attractive males have lower offspring fitness.

“To put it another way, attractive males have made so much effort into buying the red Ferrari to attract females, they have no money to put into the education of their kids.”

A Queen Elizabeth II research fellow, and a senior lecturer in the University’s School of Life Sciences, Dr Blows joined UQ from James Cook University in 1998. He graduated with honours in science at La Trobe University, where he was also awarded a PhD.

He was presented with his award at a ceremony held at the new UQ Centre on Thursday, September 26.

Media: For more information, contact Dr Mark Blows (telephone 07 3365 8382) or Brad Turner at UQ Communications (telephone 07 3365 2659)