Late Quaternary Extinction of Ungulates in Sub-Saharan Africa: a Reductionist's Approach

Abstract

Comparative osteomorphology and statistical analysis of postcranial limb bone measurements of modern African wildebeest (Connochaetes), eland (Taurotragus) and African buffalo (Syncerus) have been applied to reassess the systematic affiliations between these bovids and related extinct Pleistocene forms. The fossil samples come from the sites of Elandsfontein (Cape Province) and Florisbad (Orange Free State) in South Africa. On the basis of differences in skull morphology and size of the appendicular skeleton between fossil and modern black wildebeest (Connochaetes gnou), the subspecies name antiquus, proposed earlier to designate the Pleistocene form, can be retained. The same taxonomic level is accepted for the large Pleistocene eland, which could be named Taurotragus oryx antiquus. The long horned or giant buffalo, Pelorovis antiquus, can be included in the polymorphous Syncerus caffer stock and could therefore be called Syncerus caffer antiquus . The ecology of Pleistocene and modern Connochaetes, Taurotragus and Syncerus is discussed. A relationship between herbivore body size and climate, as Bergmann's Rule predicts, could not be demonstrated. This study furthermore questions the significance of body size and horn core morphology for Pleistocene ungulate taxonomy and suggests that the number of known (late) Quaternary species extinctions in sub-Saharan Africa may be overrated. Phyletic change is considered an alternative possibility and agonistic behaviour invoked as one of the mechanisms to explain the evolutionary shift from the Pleistocene populations of Connochaetes, Taurotragus and Syncerus to modern black wildebeest, eland and African buffalo in sub-Saharan Africa.