1Anthropology, University of Florida, 2Anthropology, The Ohio State University
Friday All day, Park Concourse
The sympatric cercopithecids of Ivory Coast’s Taï Forest consume foods of varying toughness. The diets of Colobus polykomos and Procolobus badius consist largely of leaves and may require significant masticatory activity. In contrast, the cercopithecines have less tough diets; Cercocebus atys ingests predominantly durophagous foods and Cercopithecus diana eats mainly soft fruits. Previous work suggests that mechanical challenges faced by colobines require greater loading frequencies resulting in greater remodeling in the postcanine mandibular corpus relative to Cercocebus atys. The present study aims to determine whether another cercopithecine, Cercopithecus diana, can be similarly distinguished from both colobines in terms of secondary remodeling. We expect that the differing masticatory demands in the diets of colobines and cercopithecines will be reflected in osteonal bone density.
We measured secondary osteonal density and area in thin sections prepared from the postcanine mandibular corpus of adult Cercopithecus diana specimens (N=3). These measurements were compared with remodeling data for Colobus polykomos, Procolobus badius, and Cercocebus atys. Values for osteon density were higher for colobines than for cercopithecines, with Colobus polykomos exhibiting the highest values and Cercopithecus diana, the lowest. This result suggests that a predictable relationship exists between masticatory frequency and rate of mandibular bone remodeling. The higher remodeling observed in colobines may represent a response to mitigate fatigue failure risk engendered by mastication of a folivorous diet and provides further support for an association between food material properties and the metabolic activity of bone.
Supported by NSF BCS-0922429 and 0921770.