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Punctuated evolution for the quasispecies model

Joachim Krug·Christian Karl
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Abstract

Biological evolution in a sequence space with random fitnesses is studied within Eigen's quasispecies model. A strong selection limit is employed, in which the population resides at a single sequence at all times. Evolutionary trajectories start at a randomly chosen sequence and proceed to the global fitness maximum through a small number of intermittent jumps. The distribution of the total evolution time displays a universal power law tail with exponent -2. Simulations show that the evolutionary dynamics is very well represented by a simplified shell model, in which the sub-populations at local fitness maxima grow independently. The shell model allows for highly efficient simulations, and provides a simple geometric picture of the evolutionary trajectories.

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BibTeXRIS

Joachim Krug, Christian Karl. 2002-02-04. Punctuated evolution for the quasispecies model. https://doi.org/10.1016/s0378-4371(02)01417-6

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