I am going to expand this into a post on Discover, but it is useful here. Do my parents really want me to get married?:
Abstract
Evolutionary theory predicts that based on sex-specific reproductive interests maternal grandparents increase child well-being more than paternal grandparents. In this article we study the association between grandparental involvement and children’s emotional and behavioural problems measured by the Strength and Difficulties Questionnaire (SDQ). We use the Involved Grandparenting and Child Well-Being 2007 survey, which is a representative data of 11–16-year-old adolescents from England and Wales. We test two hypotheses: (H1) There is an association between maternal grandparents’ involvement and fewer emotional and behavioral problems in children, but there is no association between paternal grandparents’ involvement and fewer emotional and behavioral problems in children; (H2) The involvement of maternal grandparents decreases the child’s emotional and behavioral problems more often than paternal grandparents’ involvement. The results support both hypotheses and are in line with the evolutionary prediction.
Highlights
* Grandparental involvement correlates with fewer emotional and behavioral problems.
* Maternal grandparents decrease the child’s emotional and behavioral problems.
* Paternal grandparents do not decrease the child’s emotional and behavioral problems.
One needs to be cautious about these evolutionary generalities, but there is a widespread cross-cultural line of research which points to the preferential benefits of maternal relatives. These results are particular striking in societies where the public social norms are strikingly biased toward the paternal lineage. When one looks at the unit of the family the affinity of the maternal grandparent to their daughter’s children makes eminent sense. But why are so many societies today highly patrilineal then? In fact the pattern cross-culturally (and in South Asia) has been to marginalize matrilineal traditions in favor of patrilineal ones.
I suspect what you are seeing is a classic “multi-level selection” dynamic at work. At the level of the clan/nuclear family there is a tendency toward more provisioning by the maternal grandmother in particular. Therefore from a functionalist perspective matrilineal societies should be more cultural “natural” (or, in the context of small scale societies a matrifocal orientation). But once you scale up the power of male lineages comes to the fore. In the competition between patrilineal and matrilineal societies those men who could rally their male kinsmen, biological and fictive, were more successful than those who were embedded in the norms whereby you defend your sister. As a matter of course matrilineal societies give women far more influence in decision making, and one might even posit that having women involved may have reduced a propensity toward conflict. Again, beneficial in the short term, but perhaps not the ticket to long term flourishing.
