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The role of size and aggression in intrasexual male competition in a social lizard species, Egernia whitii


McEvoy, J and While, GM and Sinn, DL and Wapstra, E, The role of size and aggression in intrasexual male competition in a social lizard species, Egernia whitii, Behavioral Ecology and Sociobiology, 67, (1) pp. 79-90. ISSN 0340-5443 (2013) [Refereed Article]

Copyright Statement

Copyright 2012 Springer-Verlag

DOI: doi:10.1007/s00265-012-1427-z


Competition between males is a key component of the agonistic intrasexual interactions that influence resource acquisition, social system dynamics, and ultimately reproductive success. Sexual selection theory predicts that traits that enhance success in intrasexual competition (particularly male–male competition) should be favored. In vertebrates, this often includes body size and aggression, with larger and/or more aggressive males outcompeting smaller or less aggressive conspecifics. The majority of studies consider aggression as a flexible trait which responds to local social or environmental conditions. However, aggression frequently shows considerable within-individual consistency (i.e., individuals have identifiable aggressive behavioral types). Little is known about how such consistency in aggression may influence competition outcomes. We integrated a detailed field study with a laboratory experiment to examine how a male’s aggressive phenotype and his size influence competitive interactions in Egernia whitii, a social lizard species which exhibits strong competition over resources (limited permanent shelter sites and basking sites). Individual aggression and size did not predict competition outcome in the laboratory nor did they predict home range size, overlap, or reproductive success in the field. However, winners of laboratory trial contests maintained consistent aggressive phenotypes while consistency in aggression was lost in losers. We suggest that aggression may be important in other functional contexts, such as parental care, and that alternative traits, such as fighting experience, may be important in determining competition outcome in this species.

Item Details

Item Type:Refereed Article
Keywords:intrasexual male competition, personality, aggression, lizard, behavioral consistency, behavioral plasticity
Research Division:Biological Sciences
Research Group:Ecology
Research Field:Behavioural ecology
Objective Division:Expanding Knowledge
Objective Group:Expanding knowledge
Objective Field:Expanding knowledge in the environmental sciences
UTAS Author:McEvoy, J (Dr Joanne McEvoy)
UTAS Author:While, GM (Dr Geoff While)
UTAS Author:Sinn, DL (Dr David Sinn)
UTAS Author:Wapstra, E (Associate Professor Erik Wapstra)
ID Code:81439
Year Published:2013
Web of Science® Times Cited:25
Deposited By:Zoology
Deposited On:2012-12-05
Last Modified:2017-10-31
Downloads:3 View Download Statistics

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