Peahens prefer peacocks with elaborate trains

Abstract

Peacocks, Pavo cristatus, defend small display sites and aggregate to form leks. Observations of one lek, consisting of 10 males, showed that there was considerable variance in mating success. The most successful male copulated 12 times whilst the least successful males obtained no copulations. Over 50% of the variance in mating success could be attributed to variance in train morphology; there was a significant positive correlation between the number of eye-spots a male had in his train and the number of females he mated with. Furthermore, analysis of female behaviour provided good evidence that this non-random mating is a result of a female preference. On no occasion did a female mate with the first male that courted her and, on average, females visited three different males. Females thus always reject some potential mates. For 10 out of 11 sequences ending in a successful copulation, the male 'chosen' at the end of a sequence had the highest eye-spot number among the males visited. These data support Darwin's hypothesis that the peacock's train has evolved, at least in part, as a result of a female preference. © 1991 The Association for the Study of Animal Behaviour.