High Altitude Primates, Extreme Primates, and Anthropological Primatology: Or, There is More to Human Evolution than Tool Use, Culture, or African Apes

Abstract

Within primatology, human origins research is becoming increasingly dominated by discussions that limit their scope to data from extant apes. It is argued that this trend is counterproductive and has resulted in some misleading assertions about early hominid evolution, as numerous lines of evidence suggest considerable divergence in the human and chimpanzee lineages since we shared a common ancestor. Anthropological primatologists must spread their net more widely, and utilize data from species throughout the order. Primates living at high altitudes and other comparatively marginal habitats provide critical data concerning survival in the types of extreme environments that became increasingly important throughout human evolution. The study of such animals is vital not merely because they live at high altitudes, nor that they can necessarily provide a referential model for human evolution. Rather, they yield information on the upper limits of nonhuman primate adaptation, and the range of strategies that can be utilized to reach such limits. These primates thus represent study systems ideal for elucidating general ecological principles that can be applied to particular hominids given their individual characters. Changes in altitude have predictable, quantifiable effects that influence the anatomical, physiological, and behavioral evolution of organisms. Human adaptation in relation to altitude or concurrent changes in habitat characteristics cannot be understood by considering only living apes, and, as all primates are unique, there is no single “best” living model for early hominids. The reconstruction of human origins, as exemplified by adaptation to marginal habitats, necessitates the utilization of broad evolutionary principles derived from the study of many animals.