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06:03
Procedure for Adaptive Laboratory Evolution of Microorganisms Using a Chemostat
Published on: September 20, 2016
Facilitated variation: how evolution learns from past environments to generalize to new environments
Merav Parter1, Nadav Kashtan, Uri Alon
1Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot, Israel.
Plos Computational Biology
|November 8, 2008
Summary
Facilitated variation (FV) spontaneously emerges in organisms evolving in changing environments. Organisms adapt to novel conditions by remembering past challenges and generalizing solutions, enhancing evolutionary novelty.
Area of Science:
- Evolutionary biology
- Genetics
- Developmental biology
Background:
- Evolutionary processes generate novel structures.
- Facilitated variation (FV) theory proposes that genetic changes are channeled towards potentially useful phenotypes.
- The spontaneous emergence of FV during evolution remains an open question.
Purpose of the Study:
- To investigate the conditions under which facilitated variation (FV) spontaneously emerges during evolution.
- To explore how organisms adapt to changing environments and generate novelty.
Main Methods:
- Computer simulations of logic circuits and RNA secondary structure.
- Modeling evolution in environments that systematically change over time.
Main Results:
- FV evolution is enhanced in environments with systematically varying goals.
- Organisms demonstrated memory of past environments and generalization to novel goals.
- Rapid adaptation occurred for novel combinations of familiar subgoals and entirely new subgoals.
Conclusions:
- Systematically changing, modular environments promote the spontaneous evolution of facilitated variation.
- Organisms evolve mechanisms for storing environmental information in their genomes.
- Facilitated variation theory elements like modularity and reduced pleiotropy evolve under these conditions, enhancing evolutionary generalization.
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