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Begging and provisioning of thin-billed prions, Pachyptila belcheri, are related to testosterone and corticosterone

journal contribution
posted on 01.06.2006, 00:00 authored by P Quillfeldt, J Masello, I Strange, Kate BuchananKate Buchanan
Vigorous begging is usually seen as an expression of parent–offspring conflict over limited resources. Chicks signal need by begging, but the evolution of honest signals requires the signals to be costly. Although some possible costs have been identified, the cost-inducing mechanisms underlying this widely distributed signalling system remain unclear. Because hormones associated with stress and hunger (corticosterone) and aggressive behaviour (testosterone) have deleterious side-effects, signalling costs may be coupled to the expression of such hormones, if they are closely associated with the signal. We tested whether begging in chicks of thin-billed prions (Aves, Procellariiformes) is associated with secretion of corticosterone and testosterone. Prion chicks honestly signalled their nutritional state. Begging increased with decreased body condition, both within and between chicks. Adults responded to more intense begging by delivering larger meals. Chick testosterone levels were positively correlated with measures of begging intensity and the mean body condition of chicks was correlated positively with testosterone and negatively with corticosterone. In a cross-fostering experiment, the change in testosterone and corticosterone between control and experimental periods was positively correlated with the change in begging intensity. This is the first experimental evidence that the control of chick begging by endogenously produced testosterone and corticosterone may form a mechanism controlling parental provisioning in birds, and that chick behaviour can help to explain the variation in growth patterns between individual birds.

History

Journal

Animal behaviour

Volume

71

Issue

6

Pagination

1359 - 1369

Publisher

Baillière, Tindall and Cassell [etc.].

Location

London, England

ISSN

0003-3472

eISSN

1095-8282

Language

eng

Publication classification

C1.1 Refereed article in a scholarly journal

Copyright notice

2006, The Association for the Study of Animal Behaviour