Anthropological evidence suggests that most prehistoric hunter-gatherer societies were relatively egalitarian, and that patriarchal social structures did not develop until many years after the end of the Pleistocene era, following social and technological innovations such as agriculture and domestication.[12][13][14] According to Robert M. Strozier, historical research has not yet found a specific "initiating event".[15] Some scholars point to about six thousand years ago (4000 BCE), when the concept of fatherhood took root, as the beginning of the spread of patriarchy.[16][17]

However James DeMeo argues that a specific initiating event does exist: the geographical record shows that climate change around 4000 BCE led to famines in the Sahara, Arabian peninsula and what are now the Central Asian deserts which then resulted in the adoption of warlike, patriarchal structures in order to secure food sources:

"Famine, starvation and mass-migrations related to land-abandonment severely traumatised the originally peaceful and sex-positive inhabitants of those lands, inducing a distinct turning away from original matrism towards patristic forms of behaviour."[18]

The major theory of the origin of patriarchy men dominating society points to social consequences of human reproduction. In early human history, life was short therefore to balance the high death rate and maintain the population, women had to give birth to many children.

Consequently, around the world women assumed tasks that were associated with the home and child care, while men took over the hunting of large animals and other tasks that required both greater speed and longer absences from the base camp.

As a result, men became dominant. It was the men who left camp to hunt animals, who made contact with other tribes, who traded with these groups, and who quarreled and waged war with them. It was they who accumulated possessions in trade and gained prestige by returning to the camp triumphantly, leading captured prisoners or bringing large animals they had killed to feed the tribe.

In contrast, little prestige was given to the routine, taken-for- granted activities of women who were not perceived as risking their lives for the group. Eventually, men took over society. Their sources of power were their weapons, items of trade, and knowledge gained from contact with other groups. Women became second- class citizens, subject to men’s decisions.