FEMALE CHOICE, PARASITE LOAD AND MALE ORNAMENTATION IN WILD TURKEYS

Wild turkeys, Meleagris gallopavo, exhibit a particularly striking array of ornamental characters, including a bare, brightly coloured head covered with bumpy caruncles and a distensible snood, a black hair-like beard, tarsal spurs and a large fanned tail. These characters are hypothesized to be maintained by female choice. Good genes models of female choice propose that these ornaments serve as indicators of the bearer's heritable ability to resist parasites, maximize fat deposition or attain greater age. Aesthetic models propose no such ability of ornaments to indicate these correlates of fitness. These models were tested by (1) determining the male characters assessed by captive females, using artificial and live males in mate-choice trials, and (2) examining the correlates of ornamentation in wild-caught males. Females preferred males with longer snoods and wider skullcaps. These traits were negatively correlated with coccidian oocyst loads in the faeces of wild-caught males. Snood length may also be an indicator of male energy reserves. These results are consistent with good genes models of female choice. Other aspects of male ornamentation in wild turkeys were not explained by inter-sexual selection. (C) 1995 The Association for the Study of Animal Behaviour