Why less educated mothers have children from different fathers

By casual empiricism, I noticed that uneducated mothers tend to have children from several fathers. I tended to blame this on their ignorance and shortsightedness, but apparently there is a very rational reason for this. Risk diversification.

Jinyoung Kim makes an evolutionary argument about mothers being ex-ante uncertain about the human capital of their children. In particular when the mother is less educated, she was to diversify the human capital risk of her children by having several fathers. In other words, monogamy is only a good idea if you are reasonably sure the children will all have good characteristics and are thus worth investing human capital into.This hypothesis is validated with data from the National Survey of Family Growth: a women with less education is more likely to have a different father for her next child. The same holds true for women with higher income, which is consistent with the theory because the cost of human capital investment is higher if the mother diversifies.

Consequently, if you do not like that some women have multiple fathers, which is completely rational behavior, one should provide them with the proper incentives to stick to one. This theory would tell us that this can be achieved by making sure that children get a proper education no matter what.