Effect of androgens on structure and rate of crowing in the Japanese Quail (Coturnix japonica).

To study the in uence of testosterone (T) on crowing in male Japanese quails, we combined hormonal and photoperiod manipulations of circulating androgens with a detailed analysis of the acoustic parameters of crows and of male courtship patterns. The structure of crowing was directly affected by T: high-androgen males uttered longer and lower-pitched calls than the others, call rate at dawn being related to androgens by a minimum threshold function. High- and low-callers, two consistent categories over many days, differed in their sexual performance: high-callers performed more courtship than low-callers, but there was no difference in attempted mating. Crowing is discussed as a potential target of sexual selection because, like a song, it is androgen-dependent, highly variable among individuals, and plastic in its structure at the beginning of the reproductive season.