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Updated: Jul 15, 2026
04:52
Following the Dynamics of Structural Variants in Experimentally Evolved Populations
Published on: February 3, 2023
The theory of facilitated variation
1Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA. jgerhart@berkeley.edu
Summary
Genetic changes in regulatory elements drive phenotypic variation by altering the use of conserved developmental and physiological components. This theory explains how evolution generates new traits through facilitated phenotypic variation.
Area of Science:
- Evolutionary biology
- Developmental biology
- Genetics
Background:
- Phenotypic variation is the raw material for evolution.
- Understanding the genetic basis of phenotypic variation is crucial for evolutionary studies.
Purpose of the Study:
- To propose a theory explaining how genetic changes generate phenotypic variation.
- To elucidate the role of regulatory changes in the evolution of traits.
Main Methods:
- The study proposes a theoretical framework based on existing biological principles.
- It analyzes the properties of developmental and physiological processes.
Main Results:
- Most evolved traits result from regulatory changes in conserved core components.
- Genetic changes in regulatory elements lead to heritable regulatory changes, specifying new trait configurations.
- Properties of biological processes (modularity, robustness, etc.) facilitate viable phenotypic variation.
Conclusions:
- Conserved core processes facilitate phenotypic variation by reducing the number of necessary regulatory changes and increasing genetic variation.
- This facilitated phenotypic variation is then acted upon by natural selection, driving evolutionary change.
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