Why females live longer than males

The results could help researchers understand the mechanisms involved in ageing.

"We found dramatic differences in the effects of sexual and natural selection on male and female flies. These results could help explain the sex differences in lifespan seen in many species, including humans, and the diverse patterns of ageing we observe in nature," said lead researcher professor David Hosken.

The team used populations of the fly Drosophila simulans that had evolved under different selection regimes.

The flies were then subjected to elevated and relaxed conditions of sexual and natural selection.

To elevate sexual selection, groups of males were housed with single females.

A stressful temperature was used to elevate natural selection.

The study shows that mate competition (sexual selection), along with survival (natural selection), is tougher on males than it is on females, reducing their lifespan by about a third.

There you go. Were nothing but flies. Remember that the next time you reach for the fly swatter.