Circadian patterns in male sexual behaviour and female resistance in a polygynandrous bird

Abstract

The optimal timing of sexual behaviours across a daily cycle can form a key component of mating and reproductive success. However, few studies have explored circadian rhythms in mating behaviour within the context of sexual selection and sexual conflict. Here we characterized circadian patterns in female receptivity to mating and the frequency of male mating and courtship behaviours in freely interacting captive groups of red junglefowl, Gallus gallus, in outdoor enclosures. We showed that patterns of male sexual behaviour and female resistance to mating attempts differ between the morning and evening during a 10-day mating trial. Females progressively reduced their level of resistance to male mating attempts during the early hours of the morning and progressively increased their resistance in the evening. Males did not match their mating frequencies to female receptivity and initiated mating attempts more often in the evening, but tended to perform more courtship displays in the morning. The pattern of male behaviour was associated with social status, such that dominant males courted females more often than subordinates, particularly in the morning. However, we did not find strong evidence that male social status was associated with different timing strategies. These results demonstrate circadian patterns in multiple sexual behaviours in red junglefowl, with potential consequences for sexual selection in this species and welfare management in domestic populations of closely related fowl.