Why the Donkey Did Not Go South: Disease as a Constraint on the Spread of Equus asinus into Southern Africa

Donkeys are the only ungulate definitely known to have been domesticated in Africa and were widely employed in the north of the continent and through the Sahara and the Sahel as pack animals, as well as spreading through much of the Old World. Used in Egypt by 4000 bc, they are attested in Nubia in the third millennium bc, in eastern Sudan in the second millennium bc and, in a Pastoral Neolithic context, at Narosura, Kenya, in the first millennium bc. However, they went completely unremarked by early European observers in southern Africa and appear never to have reached that region, unlike cattle and sheep, both of which reached it before the beginning of the Christian era in a process that linguistic and genetic data now firmly link to the migration of herders from East Africa. Taking its lead from previous studies of the impact of epizootic disease on the expansion through Sub-Saharan Africa of cattle and dogs, this paper asks if disease also constrained the southward movement of donkeys and, if so, what the consequences of this may have been.