Title

Habitat as a Source of Intrapopulational Variation of Ornament Size in Galápagos Lava Lizards (Microlophus albemarlensis complex)

Document Type

Article

Publication Date

2008

Publication Source

Amphibia-Reptilia

Volume

29

Issue

2

Inclusive pages

278-283

ISBN/ISSN

01735373

Peer Reviewed

yes

Abstract

Gradients in habitat structure are expected to influence the outcome of selection on traits that contribute to communicative display. Galápagos lava lizards (Microlophus albemarlensis complex) on Isla Plaza Sur in the Galápagos Islands occur across a gradient of vegetative cover. Previous work in this population has shown that traits associated with predator avoidance are magnified in habitats with low vegetative cover. This pattern suggests that predation pressure differs by habitat and thus, may act to select against the elaboration of ornamentation. We measured the size of the chin patch, an ornament known to be used in intraspecific signaling, to test this hypothesis. The area of the chin patch was dependent on both snout-vent length and residual body mass. In contrast to expectation, males had larger chin patches in the sparsely vegetated habitat suggested to have high predation risk. This result raises questions about the presumed survival cost of ornament elaboration.

Keywords

habitat, Galápagos lava lizards, Microlophus albemarlensis complex

Disciplines

Medical Sciences

 
 

Link to Original Published Item

http://dx.doi.org/10.1163/156853808784125081