Wiley, R. H., W. H. Piper, M. Archawaranon, and E. W. Thompson.   1994.   Singing in relation to social dominance and testosterone in white-throated sparrows.   Behaviour 127: 175-190.


Singing by white-throated sparrows Zonotrichia albicollis during the winter in natural situations occurred most frequently among birds with high rank in a dominance hierarchy. Genetic morph, age and sex had no significant influence on singing duri ng winter. Among testosterone-implanted birds in small groups in large aviaries, dominance rank strongly influenced singing. Testosterone-treated birds with top rank sang most frequently, those with second rank less, and those with lower rank never. As a testosterone-treated bird's rank changed in the course of regroupings with new opponents, its frequency of singing also changed.

Dominance in a group thus interacted with testosterone to promote singing. In addition, grouped birds in May before treatment with testosterone did not sing. As a consequence, it seems likely that the normal seasonal development of territorial behavior and singing involves cascading influences of endocrine states and social circumstances.


Our results with white-throated sparrows have suggested a number of interactions between social situation and hormonal state in the control of singing. In this species testosterone does not invariably activate singing. Instead, testosterone interacts w ith dominance to promote singing. Furthermore, some isolation from frequent encounters with rivals, such as that provided by dominance within a territory, evidently contributes to full endocrine development.

Many previous studies, mostly on socially isolated birds, have suggested that gonadal recrudescence leads directly to territoriality and singing. Our results here suggest that seasonal endocrine and behavioral development might instead be a cascading in teraction between hormonal effects on social behavior and social effects on hormonal activity.

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