Sarie Van Belle and howler monkeys
In December 2014, three time Leakey Foundation grantee Dr. Sarie Van Belle, of the University of Texas at Austin, was awarded a research grant for her project entitled “Paternity and kinship in socially monogamous saki and titi monkeys.”
This study will examine paternity and kinship patterns in two closely related primate species (the red titi monkey, Callicebus discolor, and the equatorial saki monkey, Pithecia aequatorialis) at the Tiputini Biodiversity Station in Yasuni National Park and Biosphere Reserve, Ecuador. Both species have been described as monogamous, a social system traditionally defined as an exclusive mating relationship between one adult female and one adult male. However, extrapair paternity, multi-adult groups, and replacements of pairmates by intruders have become increasingly acknowledged in other purportedly monogamous primate species. Genetic analyses that evaluate rates of extrapair paternity and the associated population genetic structure in socially monogamous species will enhance our understanding of aspects of this social system not readily documented with behavioral observations alone.
This comparative study has the power to identify social or ecological factors crucial in the functioning and maintenance of pair-living and monogamy, particularly because saki and titi monkeys differ in the nature of male-female relationships, the level of male care provided to offspring, and the participation of each sex to territory defense. Such analyses can contribute importantly to our understanding of the selective pressures under which monogamy evolved in primates, from which the evolution of monogamy in humans, which emerged in early hominins, can be inferred.