Phylogeny of East African cichlids  

EVOLUTIONARY GENETICS

OF CICHLID FISHES

 
  
 
 
 
 
 
 
 
Phylogenetics

The patterns of phylogenetic relationships among fishes in different lakes are easily recovered from mitochondrial DNA sequences. Lake Tanganyika holds a group of 8-10 lineages that have been distinct for 7-9 million years. The independent monophyletic radiations in lakes Victoria and Malawi have occured in the last 1-2 million years. Morphologically similar species in different lakes are therefore the result of convergent evolution. Recovery of the phylogeny of species within lakes Victoria and Malawi is complicated by the retention of ancestral polymorphisms - speciation has occurred more rapidly than fixation of alleles within species. This means that that phylogenetic trees derived from particular genes may not accurately reflect the history of the species. To overcome this problem we have scored thousands of independent restriction site polymorphisms to produce a consensus that should accurately reflect the true history of species. These phylogenies are then used to test hypotheses about the mechanisms of speciation.

Publications:

  • Kocher TD. 2003. Evolutionary biology: Fractious phylogenies (News and Views). Nature 423: 489 - 491. (PDF)
  • Albertson RC, Markert JA, Danley PD and Kocher TD. 1999. Phylogeny of a rapidly evolving clade: the cichlid fishes of Lake Malawi, East Africa. Proceedings of the National Academy of Sciences USA 96(9): 5107-5110.(PDF)
  • Kocher TD, Conroy JA, McKaye KR, Stauffer JR and Lockwood SF. 1995. Evolution of the ND2 gene in East African cichlids. Molecular Phylogenetics and Evolution 4:420-432. (PDF)
  • Meyer A, Kocher TD and Wilson AC. 1992. African fishes. Nature 350:467-468. (PDF)
  • Meyer A, Kocher TD, Basaibwaki P and Wilson AC. 1990. Monophyletic origin of Lake Victoria cichlid fishes suggested by mitochondrial DNA sequences. Nature 347:550-553. (PDF)
  • Kornfield I, McKaye K and Kocher T. 1985. Evidence for the immigration hypothesis in the endemic cichlid fauna of Lake Tanganyika. Isozyme Bulletin 18:76. (PDF)

 

 
 

 

Labeotropheus trewavasae

Labeotropheus.jpg

Pseudotropheus tropheopsTropheops.jpg

Melanochromis auratusMelanochromis.jpg
Images by Justin Marshall