Birds do it

日期:2017-12-25 02:23:09 作者:茹瘪 阅读:

HAVING lots of sex helps you to assess your mate’s fitness—at least, that’s why one species of bird does it. Scientists have various theories to explain why some species have more sex than they need to reproduce, among them that males want to be sure they are the father of any offspring, and that females want to keep the male to themselves. But David Bird and his colleagues at McGill University in Montreal found that none of the usual theories applied to the American kestrel, Falco sparverius, which is well known for its frequent copulation. Instead, the findings fit another hypothesis, say the researchers. Males and females advertise their fitness to each other by repeatedly having sex, which is “energetically costly” (Animal Behaviour, vol 56,