I believe there's a monitoring and control system outside the biology .. If we could understand (or just let it go.) the probability theory, then how can we explain the (make up) after e.g. wars disturb the balance.. and we know after some time the balance will be restored again. This for me, is a clear evidence that the balance control is In the outside. In wars or other disaster where women are greatly more than men, then probability rules and the coin doesn't follow the two-face rule.