Harshness Predicts Reproduction in Brazilian Municipalities and US Counties: A Life History Theory Approach
Vinícius Betzel Koehler1, M D Rutherford1
1Department of Psychology, Neuroscience & Behaviour, McMaster University, Hamilton, Canada.
Summary
Harsh childhood environments may lead to earlier reproduction, but divorce rates and perceived minority status showed unexpected impacts on reproductive behaviors in Brazil and the US.
Area of Science:
- Evolutionary Psychology
- Human Ecology
- Demography
Background:
- Psychosocial acceleration theory (PAT) suggests harsh childhood environments promote earlier and more frequent reproduction.
- Understanding long-term reproductive outcomes linked to early life ecology is crucial for public health and social policy.
Purpose of the Study:
- To test Psychosocial Acceleration Theory (PAT) predictions regarding harsh ecologies and reproductive behavior.
- To examine the predictive role of environmental harshness and visible minority status on later-life reproduction in Brazil and the US.
Main Methods:
- Analysis of data from 4,135 Brazilian municipalities and 2,763 US counties, using Census and American Community Survey data.
- Application of Partial Least Squares Structural Equation Modeling (PLS-SEM) for Brazil and Multivariate Linear Regression for the US.
- Inclusion of variables such as resource availability, mother's marital status, family size, divorce rates, and visible minority percentages.
Main Results:
- In Brazil, resource scarcity, young mothers, and crowded housing predicted higher rates of teenage/young adult mothers and young children.
- In the US, harshness predicted the percentage of young children, though associations were mixed.
- Divorce rates negatively predicted reproduction in both countries; visible minority status was not a significant predictor in Brazil and negatively predicted child population in the US.
Conclusions:
- Harsh ecological conditions and population child proportion significantly impact reproductive patterns over a decade later.
- Findings partially support PAT but highlight complex, country-specific interactions and unexpected predictors like divorce rates.
- Further research is needed to fully elucidate the interplay between ecology, social factors, and reproductive strategies.
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