Alexander Pashos

Kin relationships and the caregiving biases of grandparents, aunts, and uncles: a two-generational questionnaire study

Paternity certainty and matrilineal family ties have been used to explain the asymmetric caregiving of grandparents and aunts and uncles. The proximate mechanisms underlying biased kin investment, however, remain unclear. A central question of the study presented here was whether the parent-kin relationship is an important link in the caregiving. In a two-generational questionnaire study, we asked subjects to estimate the intensity of their relationships to parents, grandparents, aunts, and uncles (emotional closeness, investment received in childhood). In addition, the subjects’ parents rated their emotional closeness to their parents and siblings. We found that the parent-kin relationship was closely linked to the relatives’ child care and could partly explain asymmetric caregiving. Maternal aunts played a special role as caregivers. Especially the mother’s younger or last-born sister cared intensively for nieces and nephews, regardless of her closeness to the subjects’ mother.

Asymmetric caregiving by grandparents, aunts, and uncles and the theories of kin selection and paternity certainty: how does evolution explain human behavior toward close relatives?

Evolutionary theories explain altruism between related individuals, not only for nonhuman animals but also humans themselves. In sociobiology and evolutionary psychology, the supposedly universally found stronger matrilineal kin caregiving by grandparents, aunts, and uncles is often explained by paternity uncertainty in the male descent line. The present article provides an overview of theories and results of the evolutionary research. I will focus, in particular, on the universal caregiving pattern as well as on cultural variety in kin caregiving, the role of actual paternity certainty in the society, theoretical inconsistencies, and nonconsanguineous step relationships. From the analysis of the empirical data, I will conclude that the paternity certainty hypothesis is in fact not a very suitable explanation for the asymmetric kin caregiving found in humans. I will discuss how human behavior toward relatives, in particular grandchildren, can be alternatively explained from an evolutionary perspective.