September 10, 2009

Female insects control their sperm storage

British scientists say they've found some female insects can control the amount of sperm they store in an effort to select the best father for their young.

University of Exeter researchers say their findings represent new evidence to explain how some female insects can influence the father of their offspring, even after mating with up to 10 males.

The scientists, led by postdoctoral researcher Amanda Bretman, made the discovery during research involving female crickets, which often mate with several different males, including their closest relatives.

The scientists noted that, in general, offspring produced with close relatives are more likely to have genetic disorders and different animals employ a range of behaviors to avoid that problem, including not mating with other animals from the group in which they were born.

While crickets do not avoid mating with relatives, the new study shows they produce more offspring fathered by males that are unrelated to them.

Although the study focused on field crickets, Bretman said the findings are likely to be relevant in other insect species and possibly other sections of the animal kingdom.

The study is reported in the journal Molecular Ecology.