Thesis

Reconstructing the molecular phylogeny of giant sengis (genus Rhynchocyon)

Giant sengis (genus Rhynchocyon), also known as giant elephant-shrews, are approximately 500 g forest floor mammals that range from Central to East Africa. Previous work on giant sengi taxonomy has focused primarily on pelage color, pelage pattern, and the geographic distributions of the groups. Because there is complex phenotypic variation and large geographic ranges within some species, I chose to use genetic work to evaluate the phylogeny and classification of the genus. Genetic data were used to investigate the four currently recognized species (R. chrysopygus, R. cirnei, R. petersi, and R. udzungwensis) and seven of the eight currently recognized subspecies (R. cirnei cirnei, R. cirnei macrurus, R. cirnei reichardi, R. cirnei shirensis, R. cirnei stuhlmanni, R. p. petersi, and R. p. adersi). I used DNA extracted from fresh and historical museum samples to analyze approximately 4,700 nucleotides (2,685 bases of mitochondrial DNA and 2,019 bases o f nuclear DNA) and reconstruct a molecular phylogeny. I also investigated and genetically confirmed the identity of Rhynchocyon sp. sequences published on GenBank, and suggest that the captive Rhynchocyon populations of North American zoos are R. p. adersi. My analyses confirm the current morphological classification, with each currently recognized species forming a monophyletic clade. My phylogeny suggests that hybridization among taxa is not widespread in Rhynchocyon, that the recently reported sengi from the Boni forest of Northern Kenya is genetically similar to R. chrysopygus, and that the subspecies R. c. stuhlmanni should be elevated to full species.

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