Because human beings lived then in a world in which physical strength was the most important attribute for survival; the physically stronger person was more likely to lead. And men in general are physically stronger. (There are of course many exceptions.) Today, we live in a vastly diSerent world. The person more qualired to lead is not the physically stronger person. It is the more intelligent, the more knowledgeable, the more creative, more innovative. And there are no hormones for those attributes. A man is as likely as a woman to be intelligent, innovative, creative. We have evolved. But our ideas of gender have not evolved very much.