Identifying late Pleistocene and Holocene refugia for baboons.

Climate change has the scope to significantly modulate the distribution of floral and faunal taxa, with those regions persistently suitable to a population through the largest environmental perturbations termed "refugia". Within Africa, focus has been placed on forest refugia during glacial cycles as hotspots of biodiversity, whilst refugia for savannah species have been overlooked. We compiled a comprehensive dataset of baboon occurrences and fitted species distribution model ensembles to predict the present potential habitable range of each species and the genus as a whole. We then hindcasted these models to palaeoclimate reconstructions spanning the Late Pleistocene and Holocene in 1-thousand-year time steps to predict potentially habitable ranges throughout a full interglacial-glacial cycle. Our results indicate a substantial mosaic of refugia in the eastern African Rift Valley system, a discrete refugium in southern and south-western Africa, as well as isolated refugia across western Africa and Arabia. Orbital precession and obliquity both play a role in driving maxima and minima or predicted habitable ranges for alternate baboon species, but these appear expressed within ca. 100 thousand-year eccentricity cycles. This supports the use of full interglacial-glacial cycles, rather than simply comparing peak glacial and interglacial conditions, to determine the presence of refugia.