The process of domestication has largely eliminated the seasonal breeding cycle in many types of livestock, but most goats and sheep are still attuned to this ancient rhythm. The shorter days at the ...

Trivers (1972) proposed that females may choose to mate with males of high sexual competence (the ability to supply sufficient sperm for fertilisation). This hypothesis was tested by allowing ewes in ...

Abstract: We measured the energy cost of mate sampling by female pronghorn (Antilocapra americana), a species for which there are no apparent direct benefits of mate choice and for which the sampling ...