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Updated: Jul 24, 2026
08:10
Environmentally Induced Heritable Changes in Flax
Published on: January 26, 2011
The inheritance of phenotypes: an adaptation to fluctuating environments
1Department of Biological Sciences, Stanford University 94305, USA.
Journal of Theoretical Biology
|July 7, 1996
Summary
This study models heritable phenotypic variation in fluctuating environments. Optimal spontaneous mutation rates are inversely related to environmental cycle length, with strong selection favoring these rates and suggesting non-classical inheritance mechanisms.
Area of Science:
- Evolutionary biology
- Genetics
- Theoretical biology
Background:
- Organisms adapt to periodically fluctuating environments.
- Heritable phenotypic variations are crucial for adaptation.
- The evolution of variation rates is not fully understood.
Purpose of the Study:
- To model the evolution of spontaneous and induced heritable phenotypic variation rates.
- To investigate adaptation in periodically fluctuating environments.
- To explore the role of non-classical inheritance.
Main Methods:
- Development of simple mathematical models.
- Analysis of evolutionary dynamics in fluctuating environments.
- Simulation of selection pressures on mutation rates.
Main Results:
- Optimal spontaneous transition rates are approximately 1/n, where n is the environmental cycle length.
- Selection for optimal transition rates is surprisingly strong.
- Small cycle lengths favor non-DNA and non-classical inheritance systems.
Conclusions:
- The evolution of heritable variation rates is significant for ontogeny in unicellular and multicellular organisms.
- Non-classical genetic effects are predicted in genes controlling adaptation to fluctuating environments.
- Induced heritable variations introduce a Lamarckian component to evolution.
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