Homologies of the Anterior Teeth in Indriidae

Schwartz ('74) proposed revised homologies of the deciduous and permanent anterior teeth in living lemuriform primates of the family Indriidae. Gingerich ('77) described a juvenile specimen of Avahi and emphasized the importance of functional integrity in controlling the pattern of dental reduction in primates, neither of which supports Schwartz's interpretation. Schwartz ('78) recently reiterated his position without adequately discussing the Auahi evidence and the functional basis that probably controls dental reduction. Auahi has a deciduous dentition intermediate in morphology between that of Lemuridae and Indriidae, and similar to both. Thus the lower deciduous dental formula of Indriidae is probably 2.1.3, which is the typical and maximum deciduous complement known in living and fossil lemuriform primates. The formula of the lower permanent dentition in Indriidae is thus