Responses of African bovids to Pliocene climatic change

Abstract

Abstract The record of fossil mammals from the Shungura Formation, lower Omo Valley of southern Ethiopia, represents one of the largest and most carefully controlled samples for deciphering the responses of land faunas to global-scale climatic change. We use the abundant and continuous fossil record of the family Bovidae to analyze the effects of a late Pliocene climatic shift toward increased aridity in Africa beginning at 2.8 Ma and intensifying at about 2.4 Ma. A database consisting of 4233 specimen-based records collected under well-defined procedures is used to define patterns through time in bovid abundances while also controlling for taphonomic and other potential biases. Univariate and multidimensional (correspondence analysis) methods are used to study changes in bovid abundances through time. Our results indicate that bovids experienced an increase in species richness and a rapid episode of change in taxonomic abundances at 2.8 ± 0.1 Ma (between Members B and C), and that this shift was followed...