Political Attitude and Fertility: Is There a Selection for the Political Extreme?
Level 4 - case-series / case-control
Level 4 by design analogy (cross-sectional observational survey analysis).
OpenAlex W2900165221 · doi:10.3389/fpsyg.2018.02343
What was done
Analyzed self-reported political attitudes and completed (or near-completed) reproduction across three datasets: the World Values Survey (1981–2014, n = 152,380 across diverse countries), the Survey of Health, Ageing and Retirement in Europe (2005, n = 65,912), and the US General Social Survey (1972–2014, n ≈ 6,200).
What was found
In the global survey, both political extremes were associated with a higher average number of children compared to intermediate attitudes, with the association being more pronounced for right/conservative views. When countries were analyzed separately, the relationship was inconsistent and non-significant in most nations. In the European and US datasets, only right-wing orientation was associated with above-average offspring. In the US sample, both extremes had higher fertility in the 1970s and 1980s, but the advantage disappeared for left-wing individuals in the 1990s. The abstract reports no numerical effect sizes or confidence intervals.
Why it matters
The findings show that links between political ideology and reproductive success vary across geographic and temporal contexts, complicating simple evolutionary hypotheses about selection for specific political traits.
Limits
The abstract provides no exact numerical values, effect sizes, or test statistics. The design is observational and reliant on self-reported survey data, precluding causal inference. Results were non-significant in most individual countries, showing high heterogeneity, and unmeasured confounders are not detailed in the abstract.
Cited by
- context In the United States, the mean number of children among conservatives rose from 1.44 in 1980 to 1.67, while among liberals it declined from 1.29 to 0.87.