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...