Effects of cultural transmission of surnaming decisions on the sex ratio at birth.

The patriarchal tradition of surnaming a child after its father in Han Chinese families may contribute to their preference for sons, a major cause of the abnormally high SRB (sex ratio at birth) in China. This high SRB can subsequently contribute to the marriage squeeze on males of marriageable age. Encouraging matrilineal surnaming has been proposed as a strategy that could potentially reduce son preference and help to adjust the imbalance in SRB. Here, we model factors that are likely to influence surnaming decisions, including cultural transmission of parents' surnaming decisions, the cultural value of a daughter, reward given to matrilineal surnaming, and awareness of current imbalance in SRB. Mathematical and computational analyses suggest that offering a significant reward and raising public awareness of the problems inherent in an excess of marriage-age males may overcome the son preference and reduce the male-biased SRB.