Present address: Department of Fish Ecology & Evolution, EAWAG Centre for Ecology, Evolution and Biogeochemistry, Seestrasse 79, 6047 Kastanienbaum, Switzerland.
Article first published online: 22 MAY 2012
© 2012 Blackwell Publishing Ltd
Volume 21, Issue 13, pages 3283–3292, July 2012
How to Cite
WAGNER, C. E., McCUNE, A. R. and LOVETTE, I. J. (2012), Recent speciation between sympatric Tanganyikan cichlid colour morphs. Molecular Ecology, 21: 3283–3292. doi: 10.1111/j.1365-294X.2012.05607.x
- Issue published online: 21 JUN 2012
- Article first published online: 22 MAY 2012
- Received 28 June 2011; revision received 15 March 2012; accepted 23 March 2012
- assortative mating;
- colour morph;
- Lake Tanganyika;
Lake Tanganyika, Africa’s oldest lake, harbours an impressive diversity of cichlid fishes. Although diversification in its radiating groups is thought to have been initially rapid, cichlids from Lake Tanganyika show little evidence for ongoing speciation. In contrast, examples of recent divergence among sympatric colour morphs are well known in haplochromine cichlids from Lakes Malawi and Victoria. Here, we report genetic evidence for recent divergence between two sympatric Tanganyikan cichlid colour morphs. These Petrochromis morphs share mitochondrial haplotypes, yet microsatellite loci reveal that their sympatric populations form distinct genetic groups. Nuclear divergence between the two morphs is equivalent to that which arises geographically within one of the morphs over short distances and is substantially smaller than that among other sympatric species in this genus. These patterns suggest that these morphs diverged only recently, yet that barriers to gene flow exist which prevent extensive admixture despite their sympatric distribution. The morphs studied here provide an unusual example of active diversification in Lake Tanganyika’s generally ancient cichlid fauna and enable comparisons of speciation processes between Lake Tanganyika and other African lakes.