Fathering as Reproductive Investment.

Evolutionary theory suggests that males of all species make a choice between investing their energies in raising their children and investing their energies in mating. In most organisms, the male invests his energies in mating, while the female cares for the young. This process of selection also shapes human reproductive decisions about the level of investment to be made in mating and parenting. Longitudinal data on 19th century Mormons was analyzed to determine the effects of reproductive strategies on children. Polygynous fathers who invested resources in multiple wives were compared to monogamous men who were married to one woman at a time. Fertility, survivorship, marriage, divorce, and widowhood in the children of polygynous and monogamous men were examined. The findings revealed that monogamous men had fewer resources than polygynous men and that monogamous men tended to invest their resources in the survival of their daughters, while polygynous men utilized their resources to help their children marry. The sons of monogamous men had fewer children than their sisters and the children of polygynous men. The study attributes this phenomenon to the competition for wives in a polygynous society and the disadvantages to men who have fewer resources. Poor monogamous men may have invested more resources in their daughters because they had a better chance for marriage and reproduction than their sons. The children of polygynous men had higher mortality rates than children of monogamous men. One explanation for this finding is that polygynous men invested more resources in their own marriages early in their lives and then provided assistance to their children later. 47 references and 9 figures.