Cranney, Stephen. Forth. “The Theoretical Potential for Selection on Determinants of Fertility to Cause Aggregate Fertility Increases in Human Populations.” Journal of Biodemography and Social Biology. While prior literature on the genetics of human fertility outcomes and attitudes has generally yielded significantly positive results in developed country contexts, the implications for this dynamic on the potential for intergenerational increases in fertility is rarely raised. Here the prior literature on the subject is discussed in light of its implications for future changes due to selection, equations traditionally used in human demography are integrated into an evolutionary biological framework, and speculative calculations on the change in future fertility assuming already published numbers for parities and heritability are conducted. Limitations and overall conclusions are discussed.


Cranney, Stephen. 2016. "Is There a Stronger Association Between Children and Happiness Among the Religious? Religion as a Moderator in the Relationship Between Happiness and Child Number." Journal of Happiness Studies: 1-15. The literature on child number and happiness has progressed beyond simple associations and has begun to explore the roles of various attitudinal and environmental factors that moderate the relationship. Here the role of religiosity as a moderator in the relationship between happiness and child number is tested. This effect has not been examined before, which is surprising given the role that religion has been shown to play in child number more generally. I draw on both the psychology and demography literature to make a theoretical case that, as religiosity in the United States tends to be associated with pronatalist norms and culture, and as happiness is positively associated with fulfilling sociocultural imperatives, then, all things being equal, the more religious will have a higher happiness effect (or lower unhappiness effect) from their children than the less religious. Using General Social Survey data, my empirical analysis empirically confirmed this hypothesis, showing a positive and significant interaction term between self-identifying as very religious and child number. This interaction is partially mediated by another interaction term between higher ideal family size (measuring pronatalist tendencies) and number of children.


Cranney, Stephen. 2015.“The Association Between Pronatalist Attitudes and Belief in God in Slovenia and the Czech Republic.” Perspectives on Sexual and Reproductive Health 47(2):83-89. Research on the association between religiosity and fertility—and, particularly, on the effects of secularization on fertility desires and outcomes—has been concerned primarily with mechanisms that are fundamentally institutional and are embedded in formal religious structures. Supplementary explanations focused on noninstitutional dimensions of religiosity have never been tested. Conventional ordinary least-squares regression was used to test the association between belief in God (i.e., a personal God or some sort of life force) and fertility desires among 2,251 women aged 18–45 in Slovenia and 951 women aged 15–44 in the Czech Republic who participated in the European Family and Fertility Survey in the mid-1990s. In both samples, substantial proportions of women either were nonbelievers or believed in God but were not institutionally religious. Belief in God was independently associated with fertility desires even in analyses controlling for self-reported religiosity. Women who believed in a personal God wanted approximately 0.2 more children, and those who believed in a life force wanted approximately 0.1 more children, than nonbelievers. Results were similar across several alternative measures of religiosity. At least some of the connection between religiosity and fertility apparently is attributable to metaphysical beliefs. Future research on the effect of secularization on fertility decline should investigate the potentially distinct effects of different dimensions of religiosity.​​


Fertility