Dissolved organic carbon and unimodal variation in sexual signal coloration in mosquitofish: a role for light limitation?. Issue 1852 (5th April 2017)

• Record Type: Journal Article
• Authors: Giery, Sean T.; Layman, Craig A.
• Is Part Of: Proceedings. Volume 284:Issue 1852(2017)
• Publication Date: 2017-04-05
• Subjects: communication -- Gambusia -- natural selection -- Poeciliidae -- sexual selection -- light limitation; Biology -- Periodicals; 570.5
• DOI: 10.1098/rspb.2017.0163
• Languages: English
• ISSNs: 0962-8452

Abstract

Abstract : Natural selection plays an important role in the evolution of sexual communication systems. Here, we assess the effect of two well-known selection agents, transmission environment and predation, on interpopulation variation in sexual signals. Our model system is a series of 21 populations of Bahamian mosquitofish subjected to independent variation in optical conditions and predation risk. We show that optically diverse environments, caused by locally variable dissolved organic carbon concentrations, rather than spatial variation in predation, drove divergence in fin coloration (fin redness). We found a unimodal pattern of phenotypic variation along the optical gradient indicating a threshold-type response of visual signals to broad variation in optical conditions. We discuss evolutionary and ecological mechanisms that may drive such a pattern as well as the implications of non-monotonic clines for evolutionary differentiation.