The same causes must be held responsible for the facts that some children resemble their parents, while others do not (some being like the father and others like the mother, both in the body as a whole and in each part); and that they resemble their parents more than remoter ancestors, and resemble those ancestors more than any chance individual; and that males rather resemble their fathers, females their mothers; and that some, though resembling none of their relations, yet do at any rate resemble a human being, but others are not even like a human being but a monstrosity.