The chacma baboon (Papioursinus) through time: a model of potential core habitat regions during a glacial–interglacial cycle

The aim of this research is to understand changes in the biogeography of the chacma baboon ( Papio ursinus ) through time, by modelling potential habitat changes through the last glacial–interglacial cycle (last interglacial, glacial maximum and current conditions). An environmental envelope model in a geographic information system is used to produce a range of habitat distribution models for the chacma baboon. Initially it is modelled as a single taxon, following which the data are further divided and explored to model predicted habitats for the chacma clades during different stages of the glacial–interglacial cycle. An area of approximately 1,044,000 km 2 was identified as potentially having been within the environmental core habitat at some stage of the glacial–interglacial cycle. Of this, 63,700 km 2 of land was predicted to have been core habitat regardless of the stage of the glacial–interglacial cycle. Additionally, rainfall appears to be the environmental variable with the most limiting effect on habitat size. This is true for the current, last glacial maximum and last interglacial environmental conditions. The largest area that remains within the core habitat throughout the last glacial–interglacial cycle is found in the northern provinces of South Africa. The chacma clades appear to interact in a cyclic pattern of expansion and contraction, each clade being more prominent under different environmental conditions. It appears that grey footed chacma habitat periodically extends northward towards the yellow baboon. These findings suggest dynamic and varied progression of the chacma baboon palaeo-distributions.