A simple analytical framework to study the molecular quasispecies evolution
of finite populations is proposed, in which the population is assumed to be a
random combination of the constiyuent molecules in each generation,i.e.,
linkage disequilibrium at the population level is neglected. In particular, for
the single-sharp-peak replication landscape we investigate the dependence of
the error threshold on the population size and find that the replication
accuracy at threshold increases linearly with the reciprocal of the population
size for sufficiently large populations. Furthermore, in the deterministic
limit our formulation yields the exact steady-state of the quasispecies model,
indicating then the population composition is a random combination of the
molecules.Comment: 14 pages and 4 figure