Seasonal variation in the testicular volume of capuchin monkeys (Cebus apella) in captivity.

The study of the reproductive strategy developed by different species in order to adapt to their environmental conditions and their meaning in an evolutionary perspective is essential for understanding the mechanisms involved in the process of reproduction. Non-human primates are very interesting models for this purpose. Some species show a typical seasonal reproductive pattern, such as rhesus macaques (Macaca mulatta) [Sade, 1964; Conaway and Sade, 1965] and ring-tailed lemurs (Lemur catta) [Zuckerman, 1953], while others, such as gorillas (Gorilla gorilla) and chimpanzees (Pan troglodytes) [Puschmann, 1975], show relative independence of the environment.