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Drift on holey landscapes as a dominant evolutionary process.
Ned A Dochtermann1, Brady Klock1, Derek A Roff2
1Department of Biological Sciences, North Dakota State University, Fargo, ND 58108.
Summary
Evolutionary models do not accurately predict how genetic variation in quantitative traits is distributed. Findings suggest traits evolve across complex "holey landscapes," challenging current evolutionary theory.
Area of Science:
- Evolutionary biology
- Quantitative genetics
- Phenotypic evolution
Background:
- Organismal phenotypes are shaped by evolutionary processes, often inferred indirectly.
- Trait correlations suggest historical correlated selection and reflect adaptive landscapes.
- Expectations for quantitative trait distribution under evolutionary models are unclear.
Purpose of the Study:
- To investigate the distribution of genetic variation in quantitative traits across diverse species.
- To test the predictions of dominant evolutionary models against observed trait variation.
- To explore alternative evolutionary landscapes that may explain observed patterns.
Main Methods:
- Analyzed genetic variation in quantitative traits across six phyla and 60 species (Plantae and Animalia).
- Compared observed trait variation patterns with predictions from dominant evolutionary models.
- Evaluated consistency with evolution across high-dimensional "holey landscapes."
Main Results:
- Genetic variation in quantitative traits does not align with predictions from dominant evolutionary models.
- Observed patterns are consistent with evolution across high-dimensional "holey landscapes."
- Trait integration occurs in a manner contrary to predictions of current evolutionary theory.
Conclusions:
- Current conceptualizations and models of trait integration inadequately capture how phenotypes are shaped by evolution.
- Existing evolutionary models may fail to explain the observed distribution of genetic variation in quantitative traits.
- Further research is needed to reassess and refine evolutionary models based on these findings.
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