Diet, Dentition, and Jaw Shape in Aotus

Early research hypothesized that Aotus was a member of a specialized guild of hard-fruit and seed-eating “sclerocarpic harvesters” based largely on their dentognathic morphology. However, these food items remain conspicuously absent in reports from the field. Here, we reconsider the morphology of the feeding apparatus of Aotus, in light of the most current ecological and morphological research, and we review functional and phylogenetic themes apparent in the dentition and mandible. Aotus exhibits broad, cebine-like incisors, relatively small, sexually dimorphic canine teeth, and molar morphology that is consistent with a mixed diet of fruit and some structural carbohydrates. The vertical depth of the corpus and other morphological signals in the Aotus mandible are inconsistent with the intensive forms of ingestion and seed predation seen in pitheciids or larger cebines. In sum, though Aotus may occasionally feed on moderately challenging foods, it lacks the morphological specializations associated with sclerocarpic harvesting in platyrrhines.