Second, all three cases involved a targeted spread of farming to lands largely uninhabited by existing populations. The highly mobile Neolithic of the Nile valley extended seasonally into the adjacent steppe-desert, but avoided regions that were already densely settled, such as the Nile delta, the Sudanese gezira and the major oases (including the Fayum, where lakeside fisher-foragers prevailed, adopting and abandoning farming practices largely as it suited them).
