Once women invented farming, and began to keep and breed animals, they discovered the crucial function of the rooster and the henhouse. Fathers suddenly gained a function, and could do what only women had been able to do for all those millions of years--point at a child and say, "That is my son," "That is my daughter." Patriarchy quickly followed, beginning about five thousand years ago; a very short time in the development of our species, but covering all of recorded history.