The primate Family Cheirogaleidae is classified within the suborder Strepsirhini which includes both lemuriform primates from Madagascar and lorisiform primates from Africa and Asia. The exact placement of the Cheirogaleidae, which are found only in Madagascar, has been a problem for some time. Traditionally they have been placed with the other Madagascar primates, largely on a biogeographic basis. Most recent classifications, however, place them with the African/Asian lorisiform primates, largely on the basis of features in the base of the skull. This proposal addresses the question: are the cheirogaleid primates more closely related to the lemuriform or to the lorisiform primates? A number of data sets, including anatomical, embryological, and genetic information will examined to determine their relationships. The clarification of cheirogaleid affinities will be significant for at least three reasons. A classification is necessary that is commensurate with phylogenetic relationships. An understanding of the sister-group relationships between cheirogaleids and other strepsirhines is necessary to determine the effects of homology versus convergence. And, if cheirogaleids and lorisiforms are more closely related it will confirm that multiple migrations between Madagascar and Africa must have occurred during the history of the primates.
