With the spread of Neolithic technology to Middle and Upper Egypt in the 5th millennium bc, hunting and gathering as the main subsistence were gradually replaced by farming and herding. Although very little archaeological evidence survives, especially in Upper Egypt, agricultural villages began to appear by the 4*h millennium bc, which is called the Predynastic Period. The Egyptian Nile Valley was an almost ideal environment for cereal agriculture (see 3.4), and eventually farmers would have been able to accumulate surpluses. Agricultural surpluses were probably used to feed farmers and their families throughout the year, and some seed would have been kept for planting the next crop. But surpluses beyond the necessities of subsistence could be used to obtain goods and materials not available in farmers’ villages. Although there is evidence of long-distance trade/exchange of exotic materials from before the Predynastic Period, this greatly increased in the 4*h millennium bc, when craft production also increased - especially of artifacts such as jewelry, and carved stone palettes and vessels, which are found in elite burials of the Naqada culture in Upper Egypt.
Archaeologists have defined two different Predynastic cultures, the Buto-Ma’adi culture of Lower Egypt, and the Naqada culture of Upper Egypt, based on the distribution of two very different ceramic traditions of the 4*h millennium bc. In the north settlements are better preserved, while the southern Naqada culture is mainly known from its cemeteries, which are found in the low desert beyond the floodplain. Cultural differences went well beyond pottery types, however: the Naqada burials may symbolize increasing social complexity through time as the graves became more differentiated, in size and numbers of grave goods, whereas at Buto-Ma’adi sites burials are of a fairly simple type and seem to have had much less socio-cultural significance.