ABSTRACT
The catarrhine infraorder consists of Old World monkeys and apes, found in a wide variety of species across Africa and Asia. The descriptions of primate behavior are arranged under four headings: ecology, sociality, life cycle, and cognition. Distinctive features include greater size, greater sexual dimorphism, opposable thumbs, and the CP3 complex in the dentition. Sexual dimorphism is probably an adaptation to competition among males, but it also functions to enhance male dominance over females. Facial coloration is prominent and highly diverse in catarrhines, patterned by social and ecological factors. Breeding seasonality is more pronounced than in platyrrhines due to greater seasonal fluctuations, but never as rigid as in strepsirrhines. Individual females display a capacity for extended estrus. Two recurrent features of female sexuality are post-copulatory vocalizations and pronounced sexual swellings. Catarrhine isosexual patterns are more common and elaborated than in platyrrhines. There is evidence for greater cognitive skills in catarrhines than in other primates.
