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Updated: Mar 29, 2026
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Midface Hypoplasia and Cranial Base Morphology in Syndromic Craniosynostosis: A Comparative Analysis Study Using a Predictive Regression Model
Published on: November 4, 2025
384
A mixed model for the relationship between climate and human cranial form
David C Katz1, Mark N Grote1, Timothy D Weaver1
1Department of Anthropology, University of California, Davis, CA, 95616.
American Journal of Physical Anthropology
|December 3, 2015
Summary
This study quantifies climate
Area of Science:
- Human evolutionary biology
- Quantitative genetics
- Paleoclimatology
Background:
- Human cranial form is influenced by population structure.
- Previous studies show correlations between cranial distances and climate variables.
- Estimating the biological significance of climate effects requires effect size, not just distance.
Purpose of the Study:
- To estimate the magnitude of climate effects on human cranial morphology using a multivariate mixed model.
- To overcome limitations of distance-based methods in quantifying ecological predictor effects.
- To apply advanced quantitative genetics models to high-dimensional cranial data.
Main Methods:
- Utilized innovations extending quantitative genetics mixed models to multivariate observations.
- Applied the model to a subset of the Howells craniometric dataset.
- Estimated morphological effects linked to climate predictors.
Main Results:
- Identified a substantial linear association between several cranial measurements, especially vault breadth, and climate.
- The multivariate model including a climate predictor demonstrated superior performance in model comparison.
- Effect sizes for climate predictors were quantifiable.
Conclusions:
- Confirmed and quantified the relationship between climate and human cranial form.
- Demonstrated the utility of mixed models for estimating the biological importance of ecological factors.
- Highlighted the potential of mixed models for evolutionary studies disentangling population structure and selection drivers.
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