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Published on: August 12, 2019
A test of the hypothesis that correlational selection generates genetic correlations
Derek A Roff1, Daphne J Fairbairn
1Department of Biology, University of California, Riverside, California 92521, USA. Derek.roff@ucr.edu
Evolution; International Journal of Organic Evolution
|September 6, 2012
Summary
Correlational selection on two traits aligns the G matrix with the selection gradient. This meta-analysis confirms that genetic correlations match selection signs and magnitudes, supporting this evolutionary theory.
Area of Science:
- Evolutionary biology
- Quantitative genetics
Background:
- Correlational selection influences trait evolution by favoring specific trait combinations.
- Theoretical models predict the G matrix's orientation based on correlational selection gradients.
Purpose of the Study:
- To test the hypothesis that correlational selection orients the bivariate G matrix.
- To empirically validate predictions regarding the relationship between correlational selection gradients and genetic correlations.
Main Methods:
- Meta-analysis of empirical studies.
- Utilized estimates of correlational selection gradients.
- Analyzed measures of trait correlations.
Main Results:
- Results supported the prediction that the sign of the correlational selection gradient matches the genetic correlation.
- Findings also supported the prediction that the gradient is positively correlated with the genetic correlation's value.
Conclusions:
- The study provides empirical support for the theoretical link between correlational selection and the orientation of the G matrix.
- Correlational selection is shown to generate genetic correlations, influencing evolutionary trajectories.
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