Exploring population level variation in the later Pleistocene Cercopithecids from the Middle Awash study area (Afar Rift, Ethiopia)

Abstract

The anatomical and behavioral variation within a population provides the core of evolution by natural selection. Unfortunately, paleoanthropologists rarely have the opportunity to investigate population-level variation because of the scarcity of the paleontological record. Mammalian terrestrial fossils are rare, and fossils of primates even more so. However, there is a unique opportunity to study population-level variation within the primate fossil assemblages recovered from the later Pleistocene deposits at Halibee in the Middle Awash research area in the Afar Region of Ethiopia. In total, 977 non-human primates have been recovered spanning two main time horizons, the Faro Daba beds (ca. 100,000 years ago) and the Chai Baro beds (>158,000 years) of the Dawaitoli Formation. Three taxa have been described within this large assemblage: cf. Chlorocebus (n = 328), Colobus cf. Guereza (n = 360), and Papio hamadryas ssp. (n = 143).