On adaptive accuracy and precision in natural populations
Thomas F Hansen1, Ashley J R Carter, Christophe Pélabon
1Department of Biological Science, Florida State University, Tallahassee, FL 32306, USA. thomas.hansen@bio.uio.no
The American Naturalist
|July 29, 2006
Summary
Adaptation is better understood as accuracy, not optimality. Selection favors precise development, where genotypes accurately realize target phenotypes, minimizing distance to fitness optima.
Area of Science:
- Evolutionary biology
- Quantitative genetics
Background:
- Traditional adaptation models focus on population mean fitness relative to an optimum.
- Natural selection acts on individual fitness, influenced by phenotype realization.
- Genotypes may not produce invariant phenotypes, impacting fitness.
Purpose of the Study:
- To propose a conceptual shift in understanding adaptation from optimality to accuracy.
- To investigate the role of developmental precision in adaptation.
- To quantify the contribution of imprecise development to phenotypic variation.
Main Methods:
- Literature survey to assess developmental imprecision in wild populations.
- Conceptual framework defining adaptive inaccuracy and accuracy.
- Analysis of adaptive accuracy components: target deviance and realization precision.
Main Results:
- Developmental imprecision is a substantial and variable component of phenotypic variation across traits.
- Adaptive accuracy, encompassing target deviance and realization precision, offers a more nuanced view.
- Selection may favor improved developmental precision for many traits.
Conclusions:
- Conceptualizing adaptation as accuracy provides a more comprehensive framework.
- Developmental precision is a critical, often underestimated, factor in evolutionary adaptation.
- Further research into selection for precision is warranted.
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