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Testosterone influences basal metabolic rate in male house sparrows: a new cost of dominance signalling?

journal contribution
posted on 07.07.2001, 00:00 authored by Kate BuchananKate Buchanan, M R Evans, A R Goldsmith, D M Bryant, L V Rowe
Sexually selected signals of individual dominance have profound effects on access to resources, mate choice and gene flow. However, why such signals should honestly reflect individual quality is poorly understood. Many such signals are known to develop under the influence of testosterone. We conducted an experiment in male house sparrows in which testosterone was manipulated independently during two periods: before the onset of the breeding season and prior to the autumn moult. We then measured the effects of these manipulations on basal metabolic rate and on the size of the chest bib, a sexually selected signal. The results demonstrate that testosterone simultaneously affects both signal development and basal metabolic rate in the house sparrow (Passer domesticus). This evidence, therefore, supports a novel conclusion: that testosterone-dependent signals act as honest indicators of male quality possibly because only high-quality individuals can sustain the energetic costs associated with signal development.

History

Journal

Proceedings of the Royal Society B: biological sciences

Volume

268

Issue

1474

Pagination

1337 - 1344

Publisher

Royal Society of London

Location

London, Eng.

ISSN

0962-8452

Language

eng

Publication classification

C1.1 Refereed article in a scholarly journal

Copyright notice

2001, The Royal Society