Comparative feeding ecology of the Uakari and Bearded Saki, Cacajao and Chiropotes

Abstract

The ecology of two closely related pitheciine monkeys, Cacajao calvus and Chiropotes albinasus, is reviewed, with an emphasis on their frugivorous feeding habits and the habitats they prefer. Although both consume a similar diet of young seeds of common plant taxa, they employ different foraging strategies. Chiropotes forages as a single unit in large multi-male/multi-female groups, whereas Cacajao aggregates split into parties of flexible subunits. These differences relate to their contrasting habitat preferences. Chiropotes live in the non-inundated terra firme forests and Cacajao live in the flooded várzea forests. Each habitat type is characterized by a distinctive taxonomic and spatial composition of local fruit trees, and they also contain different animal faunas. An attempt to reconstruct the evolutionary history of these monkeys is made, based upon the geomorphological evolution of the Amazoniau region. © 1989.