Center for the Study of Human Origins, Department of Anthropology, New York University, New York Consortium for Evolutionary Primatology, (NYCEP)
Saturday 10:30-10:45, 200ABC
Galagids are probably “the least known of all primates” and their systematics is one of the most long-standing problems in primatology. Species diversity has likely been underestimated due to the lack of morphological variation, and most species have been described using bioacoustic data, leading to a large, but quite controversial, increase in species number. In the present study, I revisit the contentious relationships within African Galagidae by analyzing 20 nuclear loci (>13kb) and mitochondrial sequences from all major galagid lineages. Traditional phylogenetic methods (maximum likelihood and Bayesian inference) as well as a species-tree/gene-tree approach were used to analyze the dataset. Relationships among the main clades are well resolved and support the needle-clawed galagos (Euoticus) as the most basal genus, which thus represents a unique lineage within Strepsirrhines. Galagoides is paraphyletic, suggesting the presence of two separate genera for the dwarf galagos: the Eastern forms (e.g., zanzibaricus complex) actually cluster closer to greater and lesser galagos than to the Western species (thomasi/demidoff). I propose that morphological and ecological similarities within dwarf galagos are likely a consequence of either convergence or plesiomorphic retentions. Molecular dating indicates deep evolutionary divergences within the family: the origin of crown galagids occurred in the early Oligocene and most extant genera were already present by the late Miocene. Such deep divergence within several lineages might also suggest the presence of multiple cryptic species, for which better geographic sampling is required. Finally, results are discussed in light of climatic and biogeographical events to explain galagid diversification in Africa.
This research was supported by funding from a National Science Foundation Doctoral Dissertation Improvement Grant (#1128975), Primate Conservation Inc., Margot Marsh Biodiversity Foundation, and the International Primatological Society.