complex adaptation
Pál C & Papp B 2017 Evolution of complex adaptations in molecular systems. Nat Ecol Evol 1:1084-1092.
- the lack of consensus on the relative roles played by mutation, recombination and random genetic drift hinders empirical tests
- the role of recombination is particularly controversial
- it can either facilitate the escape from local fitness peaks by combining mutations from different individuals, or hinder it by breaking up adaptive combinations
- only low recombination rates can speed up the crossing of fitness valleys
- high rates are predicted to be disadvantageous
- alteration of the adaptive landscape by environmental change permits exploration of new regions of the sequence space that are otherwise selected against
- this process leads to superior phenotypes
- complex traits can emerge in complex environments without the need to invoke neutral exploration of genotype space
- antagonistic pleiotropy is prevalent
- mutations deleterious in one environment are beneficial in another
- mutations with antagonistic effects, rather than neutral mutations, contribute to the evolution of complex adaptations
- to obtain a desired function, evolutionary engineering could be facilitated by temporally varying the selection regime
- in computer science, standard genetic algorithms have a tendency to converge quickly to a local solution, and hence frequently fail to identify more promising regions of the search space
- application of dynamically changing 'environments' offers a natural strategy to maintain the diversity required to explore the adaptive surface
