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Population Structure And Phylogenetic History Of The Lake Malawi Cichlid Species Flock, Jeffrey Alan Markert

Doctoral Dissertations

The cichlid species "flocks" which are endemic to the East African Rift Valley are characterized by frequent lineage splitting events which have led to the rapid evolution of high levels of taxonomic diversity. Changes in water level cause these habitat patches to be chronically unstable, hypothetically speeding the process of genetic differentiation through the combined effects of genetic drift and selection. Allele frequencies at four simple sequence repeat loci indicate low levels of gene flow in two rock dwelling fish species, Melanochromis auratus and Labeotropheus fuelleborni, collected from the Nankumba Peninsula in southern Lake Malawi. Small interruptions in habitat cause …