Large families in the United States are more likely to oppose abortion and same-sex marriage, sustaining "family-values" conservatism through differential fertility, a study suggests. Through the intergenerational transmission of attitudes, differential fertility across families can shape public opinion on contentious sociopolitical issues. To examine the link between family size and family-values conservatism, Tom Vogl and Jeremy Freese analyzed data from 12,017 adults over the age of 25 years who participated in the US General Social Survey between 2004 and 2018. The results revealed that opposition to abortion and same-sex marriage increases with family size. The relationship between a greater number of siblings and stronger traditional family conservatism is largely explained by greater religiosity and lower educational attainment. Across all survey years, the association between the number of siblings and attitudes was responsible for increasing opposition to abortion from 53% to 57%. Similarly, the association between the number of siblings and attitudes was responsible for increasing opposition to same-sex marriage from 38% to 41% across all survey years. By 2018, differential fertility in the last generation was responsible for a 16.7% increase in opposition to same-sex marriage. According to the authors, differential fertility can sustain large pockets of opposition to cultural change, despite the broad and overall rise in liberalism in the US population.
Article #19-18006: "Differential fertility makes society more conservative on family values," by Tom S. Vogl and Jeremy Freese.
MEDIA CONTACT: Tom Vogl, University of California San Diego, La Jolla, CA; e-mail: email@example.com
Proceedings of the National Academy of Sciences