This audiobook has some very interesting points about human sexuality and how the social situations of today and the last 10,000 years have changed it.  The book points out that there are similarities between us and our closest ape cousins that demonstrate the tendency for multi-male multi-female relationships among members of close groups (less than 150).  The movement to agriculture seems to be the defining moment in the change, making it more possible to accumulate wealth.  With the accumulation of wealth came also the accumulation of power and control, making people dependent on the powerful person instead of purely co-dependent.  There are some communities living in the world that still live by multi-male multi-female relations, but those people are still fully co-dependent and living in small communities.  The current fast paced life, massive cities, and constant changing social circles make this small co-dependent structure not feasible.  From the number of scandals that are on the news, and quantity of failed mariages that fails it is certain that we have not evolved beyond this (not to imply that we should be evolving in that direction).  We are mostly just living in a society where control is driven by prudes who push a warped view of sexuality that they themselves do not always follow.

Audible Link