1. Do you have a source for that claim? You probably only run into a significant lack of variation if the gene pool is extremely small, i.e. in incestuous relat

1. Do you have a source for that claim? You probably only run into a significant lack of variation if the gene pool is extremely small, i.e. in incestuous relationships. 2. As far as I know this is not fully known yet. It is conceivable that the offspring did just fine in polygamous relationships or just inside the secure environment that the pack provides. There is, for example, some evidence that intensive mothering is ineffective [1]. Among Great Apes the upbringing of the young is commonly shared between the members of the pack and the identity of the father is unknown. Moreover, consider that the importance of education only became really significant within the past 100-50 years, or so, but the concept of marriage in Western culture is much older than that [2]. [1] http://onlinelibrary.wiley.com/doi/10.1111/jomf.12170/abstract http://onlinelibrary.wiley.com/doi/10.1111/jomf.12170/abstra... [2] https://en.wikipedia.org/wiki/Marriage#Europe https://en.wikipedia.org/wiki/Marriage#Europe