Interpretation of Primate Behavior, Ambulation and Biomechanics: Caveat Arthritis

Abstract

Copyright: © 2012 Rothschild B. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Analysis of ambulation or biomechanics on the basis of functional morphology (anatomical shape of bones and location of muscle origins and insertions) seems predictive of potential behaviors [1-3]. It delineates possible range of limb motion and potential uses of the limb, and may seem all that is available for examination of the fossil primates. Actually, evidence of new bone formation at sites of muscle or tendon insertion (entheses) and osteoarthritis further identify how the limb is actually utilized [4-6]. The stress of limb activity promotes osteoblastic reaction [4], with visible evidence. The combination of these physical manifestations allows speculation as to organismal behavior. Establishing confidence (that a given speculation accurately portrays the life of a primate) requires an additional step: Observation of limb utilization in vivo in the natural setting. This requires observations in the wild. Performance of such observations in artificial environments allows more controlled study, but the character of the artificial environment must also be considered. Caya Santiago contains a phenomenal project, in which rhesus macaques have been given their own island. It is a natural habitat in a hurricane-susceptible region. In contrast to the two-three levels of canope in their natural environment [7], there is generally only one layer of canape on this Puerto Rican island. The macaques appear to spend more time on the ground than they do in their “home” environment. A behavior alteration, with osseous manifestations: They have a higher frequency of osteoarthritis than do their conspecifics in Africa [8-11]. Osteoarthritis is extremely rare in the natural habitat, with frequency less than 1% in primates [812]. There is another factor which may affect behavioral observations, both in generated habitats (e.g., Caya Santiago) and in the wild, what might be referred to as the behavioral analogy to the Heisenberg uncertainty issue in physics. Does the very fact of observation alter behavior? And, some investigators do more than just observe (e.g., Diane Fossey).