Table of Contents
International Journal of Evolutionary Biology
Volume 2011 (2011), Article ID 426179, 7 pages
http://dx.doi.org/10.4061/2011/426179
Research Article

Segregation of Species-Specific Male Attractiveness in Hybrid Lake Malawi Cichlid Fish

1Evolutionary Biology Group, Biological Sciences, University of Hull, Hull HU6 7RX, UK
2Department of Zoology, University of Gothenburg, P.O. Box 463, 405 30 Gothenburg, Sweden
3University of Basel, Zoological Institute, Vesalgasse 1, 4051 Basel, Switzerland
4Easton College, Easton, Norwich, Norfolk NR9 5DX, UK
5School of Environmental Sciences, University of East Anglia, Norwich NR4 7TJ, UK
6Swiss Federal Institute of Aquatic Science and Technology (Eawag), Centre for Ecology, Evolution & Biogeochemistry, Seestrasse 79, 6047 Kastanienbaum, Switzerland
7Institute of Ecology and Evolution, University of Bern, Baltzerstrasse 6, 3012 Bern, Switzerland
8School of Biological Sciences, Bangor University, Gwynedd LL57 2UW, Wales, UK

Received 3 December 2010; Accepted 14 February 2011

Academic Editor: Kristina M. Sefc

Copyright © 2011 Ola Svensson et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Among the huge radiations of haplochromine cichlid fish in Lakes Malawi and Victoria, closely related species are often reproductively isolated via female mate choice although viable fertile hybrids can be produced when females are confined only with heterospecific males. We generated F2 hybrid males from a cross between a pair of closely related sympatric cichlid fish from Lake Malawi. Laboratory mate choice experiments using microsatellite paternity analysis demonstrated that F2 hybrid males differed significantly in their attractiveness to females of the two parental species, indicating heritable variation in traits involved in mate choice that may contribute to reproductive isolation between these species. We found no significant correlation between male mating success and any measurement of male colour pattern. A simple quantitative genetic model of reproductive isolation suggests that there may be as few as two chromosomal regions controlling species-specific attractiveness. We propose that adaptive radiation of Lake Malawi cichlids could be facilitated by the presence of genes with major effects on mate choice and reproductive isolation.