The Owl Monkey Project
The Owl Monkey Project, started in 1996 by Dr. Eduardo Fernandez-Duque, is a multi-disciplinary program on the owl monkeys of the Argentinean Chaco. Studies are conducted on population biology, demography, behavior, genetics, endocrinology and conservation in collaboration with numerous institutions and colleagues and with the support of international and Argentinean funding agencies.
Fernandez-Duque started the project because he was interested in the evolution of social relationships, monogamous mating systems and parental care. In particular he was interested in examining the roles that males and females have in the maintenance of a monogamous social system. Owl monkeys live in social groups that include one pair of reproducing adults and between one and four young.
The testes of male owl monkeys (on the left) bear a great resemblance to the labia of females (on the right). Owl monkeys are no exception to the rule that males and females of monogamous species tend to be similar in their physical appearance.
Owl monkeys’ relatively large eye orbits are unequivocal evidence of their nocturnal habits. They are the only primates in the Neotropics adapted to a nocturnal lifestyle. The owl monkey species being studied in Argentina is cathemeral; in other words the monkeys are active during the day, as well as during the night.
Though active during dusk and dawn, to follow the owl monkeys’ full activity cycle, night research is sometimes require. Here, we use night-vision goggles that allow us to follow owl monkeys during the night after we have located them using radio telemetry.