| Pitheciidae and other Platyrrhine Seed Predators: The Dual Occupation of the Seed Predator Niche during Platyrrhine Evolution Kay, R.K. & M. Takai The fossil record for crown Pitheciidae (the titi monkeys-- Callicebus, and the sakis and uakaries-- Pithecia, Chiropotes and Cacajao) and its corresponding stem group, is restricted to the middle Miocene, Colombia (~12 Ma) and northern Patagonian Argentina (15 Ma). The Patagonian record, although it consists of teeth, jaw fragments and a talus of just one species, establishes that the front- tooth specializations of the pitheciines (sakis and uakaris), associated with seed predation, were already established and, by inference, that the titi-monkey clade must already have separated from pitheciines before 15 Ma. Colombian fossil pitheciids include the first definite record of titi monkeys —Miocallicebus— and three stem pitheciines. The best preserved of these is Cebupithecia, represented by a partial skull and skeleton. Colombian Miocene pitheciines exhibited a range of seed predation adaptations; however, the tail of Cebupithecia was elongate, unlike living sakis and uakaries. We have no fossil record of any crown pitheciine. Interestingly, a group of extinct species called Soriacebidae found in the early Miocene of Patagonian Argentina (at > 45 degrees South) is argued to be related to Pitheciinae. Soriacebids occupied a seed-predation niche broadly similar to pitheciines. However details of their anatomy, especially in a more primitive recently discovered early soriacebid from about 20 Ma, demonstrate that soriacebids occupied the seed predator niche independently from pitheciines and are a striking example of convergent adaptation. voltar a programação do simpósio |