It has been claimed that Zea mays existed in Africa before the discovery of America, but the plant is more generally considered to be a native of America, which could have spread through other continents only in post-Columbian times.
This latter opinion has recently been challenged by several writers. Jeffreys, for instance, has since 1953 consistently maintained that on arrival in Guinea the Portuguese found Zea mays already well established there, as the cereal they called milho zaburro, previously introduced by the Arabs, who would have visited America long before Columbus. On the other hand, V. de Magalhães Godinho, pertinently refuting many of Jeffreys's reasonings and identifications, has put forward the view that, before the Portuguese voyages of discovery, there existed in Africa a variety of Zea mays, which was subsequently replaced by the American variety; the Portuguese would have become familiar with this variety in Morocco, and it would be this plant which they called milho zaburro, or milho maçaroca. To both these authors the designations milho maçaroca and Zea mays are indisputably synonymous.