Journal
EVOLUTION
Volume 67, Issue 11, Pages 3120-3131Publisher
WILEY
DOI: 10.1111/evo.12192
Keywords
Adaptation; epistasis; models; simulations; molecular evolution; population genetics
Categories
Funding
- Burroughs Wellcome Fund
- David and Lucile Packard Foundation
- James S. McDonnell Foundation
- Alfred P. Sloan Foundation
- U.S. Department of the Interior and Defense Advanced Research Projects Agency [W911NF-12-1-0552]
- U.S. Army Research Office [RFP-12-16]
- Foundational Questions in Evolutionary Biology Fund
Ask authors/readers for more resources
The contribution to an organism's phenotype from one genetic locus may depend upon the status of other loci. Such epistatic interactions among loci are now recognized as fundamental to shaping the process of adaptation in evolving populations. Although little is known about the structure of epistasis in most organisms, recent experiments with bacterial populations have concluded that antagonistic interactions abound and tend to deaccelerate the pace of adaptation over time. Here, we use the NK model of fitness landscapes to examine how natural selection biases the mutations that substitute during evolution based on their epistatic interactions. We find that, even when beneficial mutations are rare, these biases are strong and change substantially throughout the course of adaptation. In particular, epistasis is less prevalent than the neutral expectation early in adaptation and much more prevalent later, with a concomitant shift from predominantly antagonistic interactions early in adaptation to synergistic and sign epistasis later in adaptation. We observe the same patterns when reanalyzing data from a recent microbial evolution experiment. These results show that when the order of substitutions is not known, standard methods of analysis may suggest that epistasis retards adaptation when in fact it accelerates it.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available