Reconstructing the Molecular Phylogeny of Giant Elephant-shrews (genus Rhynchocyon)
Reconstructing the Molecular Phylogeny of Giant Elephant-shrews (genus Rhynchocyon)
Sunday, 15 February 2015
Exhibit Hall (San Jose Convention Center)
Giant sengis (genus Rhynchocyon), also known as giant elephant-shrews, are small mammals restricted to sub-Saharan Africa. Previous work on giant sengi taxonomy has focused primarily on pelage (hair) morphology and the distributions of the groups. Because there is complex morphological variation within some groups these taxa lend themselves to genetic work. We used genetic data to investigate the validity of the four recognized species (Rhynchocyon chrysopygus, R. cirnei, R. petersi, and R. udzungwensis) and the eight recognized subspecies (R. cirnei cirnei, R. cirnei hendersoni, R. cirnei macrurus, R. cirnei reichardi, R. cirnei shirensis, R. cirnei stuhlmanni, R. petersi petersi, and R. petersi adersi). Using DNA extracted from fresh and historical museum samples, we analyzed 5,800 nucleotides (3.4 kb of mitochondrial DNA and 2.4 kb of nuclear DNA). These data were used to reconstruct a phylogeny of giant sengis and test taxonomic boundaries. Each recognized species formed a clade in our analyses. R. cirnei has multiple well-differentiated subspecies that support their distinct histories in their biogeographical regions (e.g. R. cirnei macrurus in South Eastern Tanzania, R. cirnei stuhlmanni in the Congo Basin, R. cirnei reichardi in the mountains of Tanzania, and R. cirnei cirnei in southeastern Mozambique).