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arXiv · 0911.5366

Quantifying Slow Evolutionary Dynamics in RNA Fitness Landscapes

P. Sulc·A. Wagner·O. C. Martin
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Abstract

We re-examine the evolutionary dynamics of RNA secondary structures under directional selection towards an optimum RNA structure. We find that the punctuated equilibria lead to a very slow approach to the optimum, following on average an inverse power of the evolutionary time. In addition, our study of the trajectories shows that the out-of-equilibrium effects due to the evolutionary process are very weak. In particular, the distribution of genotypes is close to that arising during equilibrium stabilizing selection. As a consequence, the evolutionary dynamics leave almost no measurable out-of-equilibrium trace, only the transition genotypes (close to the border between different periods of stasis) have atypical mutational properties.

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P. Sulc, A. Wagner, O. C. Martin. 2009-11-28. Quantifying Slow Evolutionary Dynamics in RNA Fitness Landscapes. https://doi.org/10.1142/s0219720010005075

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