The evolution of genetic canalization under fluctuating selection
1Zoology Institute, University of Basel, Switzerland. t.kawecki@unibas.ch
Evolution; International Journal of Organic Evolution
|August 11, 2000
Summary
Genetic canalization, a trait
Area of Science:
- Evolutionary biology
- Population genetics
Background:
- Rapidly fluctuating selection can be maladaptive.
- Genetic variation expressed at the phenotypic level impacts evolutionary response.
- Genetic canalization reduces the phenotypic expression of genetic variation.
Purpose of the Study:
- To investigate the conditions favoring the evolution of genetic canalization.
- To determine if genetic canalization evolves under fluctuating selection regimes.
Main Methods:
- Developed two- and multilocus models.
- Simulated alternating linear and fluctuating Gaussian selection.
- Analyzed the effects of a canalizing modifier gene on fitness.
Main Results:
- Canalizing modifiers are favored under rapidly fluctuating selection (period ≤ 8 generations).
- Modifier genes reduce phenotypic consequences of past selection and genetic response.
- Fluctuating Gaussian selection favors canalization only under weak to moderate strength.
Conclusions:
- Genetic canalization can evolve under fluctuating selection, broadening previous theories.
- Modifier genes play a crucial role in adapting to changing selective pressures.
- The evolution of canalization depends on the type and strength of fluctuating selection.
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