Historical antecedents and recent innovations in pitheciid (titi, saki, and uakari) feeding ecology

The modern pitheciids (titis, sakis, and uakaris) of northern South America represent one of the earliest radiations of platyrrhines and demonstrate morphological adaptations and ecological strategies for seed eating. While seeds can provide reliable resources for relatively long periods of time, they are often well protected by thick husks and hard seed coverings. Seeds also tend to be rich in lipids, but they may also be high in indigestible fiber. Even though seed eaters are found in each major primate radiation, only the pitheciids demonstrate primary adaptations for eating seeds. In this partly historical, partly contemporary review, I examine the ecological and anatomical correlates of seed eating. It is dedicated to two well-known field primatologists: ecologist and conservationist J. Márcio Ayres; and anatomist and ecologist Warren G. Kinzey. Using observations in Kinzey (1992, Am J Phys Anthropol, 88, pp. 499-514) as a framework, I provide context and analysis for the intervening three decades of pitheciid research to identify what we know about this understudied group of primates and propose directions for future work.