Eggs of a Female Japanese Quail Are More Likely to Be Fertilized by a Male That She Prefers

Male Japanese quail (Coturnix japonica) that conspecific females preferred in a 10-min, forced-choice test of affiliative preference were more likely than were males not preferred in such a test to fertilize females' eggs when subsequently mated with them, although preferred and nonpreferred males mated equally often with females. Further, the probability that a nonpreferred male would fertilize a female's eggs was significantly increased if …