The 85th Annual Meeting of the American Association of Physical Anthropologists (2016)

Phenotypic and genetic ontogenetic integration of squirrel monkey (Saimiri boliviensis) age-specific body mass


1Department of Anthropology, University of Missouri, 2Department of Veterinary Sciences, Michale E. Keeling Center for Comparative Medicine and Research, University of Texas MD Anderson Cancer Center

April 16, 2016 , Atrium Ballroom A/B Add to calendar

Primate ontogeny is prolonged compared to other mammals of comparable body size and often includes growth spurts. This long duration and multiphasic nature of primate growth offers opportunities for both compensatory canalization of adult size and potential dissociation of sizes at distant age points. We addressed these factors in a large sample of captive Bolivian squirrel monkeys (Saimiri boliviensis boliviensis) interlinked through a well-known genealogy.

Phenotypic variances across developing age classes are consistent with compensatory growth while bivariate correlations identify dissociation between ages before and after the first birthday. Parallel "animal model" quantitative genetic analysis yielded narrow-sense heritability estimates of mass that were initially small but rose quickly to plateau near h2≈0.5 in adulthood. Additionally, we highlight normative patterns of mass ontogeny in Saimiri. These include clear sexual bimaturism with a strong adolescent spurt in males even after adjusting for seasonal fattening, and the absence of any sign of a previously suggested period of temporary growth cessation in late infancy.

Supported in part by NIH grant P40 OD010938 to the Michale E. Keeling Center.