White Rose University Consortium logo
University of Leeds logo University of Sheffield logo York University logo

Testes asymmetry, condition and sexual selection in birds: an experimental test

Birkhead, T.R., Fletcher, F. and Pellatt, E.J. (1998) Testes asymmetry, condition and sexual selection in birds: an experimental test. Proceedings of the Royal Society Series B: Biological Sciences, 265 (1402). pp. 1185-1189. ISSN 1471-2954

Full text available as:
[img]
Preview
Text
birkheadtr8.pdf

Download (147Kb)

Abstract

The functional significance of the marked directional asymmetry in testes size observed in many bird species is obscure. Møller suggested that (i) the smaller of the two testes serves a compensatory role and increases in size (and hence reduces asymmetry) when the larger one is defective in some way, and (ii) as a consequence, the degree of directional asymmetry in testes size reflects male quality and covaries positively with the expression of secondary sexual traits.We conducted an experimental test of these two hypotheses in the zebra finch,Taeniopygia guttata. Neither hypothesis was supported. First, there was no significant relationship between the size of the left testis and relative testes asymmetry. Second, we obtained no support for the hypothesis that the degree of directional asymmetry in testes mass covaried with condition. On the contrary, directional asymmetry in testes mass was signifcantly greater in birds whose condition was experimentally reduced, compared with control birds. Moreover, we found no significant relationships between testes asymmetry and secondary sexual traits. We conclude that directional asymmetry in testes size does not reflect male condition in the zebra finch.

Item Type: Article
Copyright, Publisher and Additional Information: © 1998 The Royal Society
Institution: The University of Sheffield
Academic Units: The University of Sheffield > Faculty of Science (Sheffield) > School of Biological Sciences (Sheffield) > Department of Animal and Plant Sciences (Sheffield)
Depositing User: Sherpa Assistant
Date Deposited: 01 Jul 2005
Last Modified: 07 Jun 2014 03:31
Published Version: http://www.journals.royalsoc.ac.uk/link.asp?id=v5w...
Status: Published
Refereed: Yes
Identification Number: 10.1098/rspb.1998.0417
URI: http://eprints.whiterose.ac.uk/id/eprint/537

Actions (login required)

View Item View Item