Fixation of a rare allele with weak selective advantage in finite populations
Trajectories of a weakly
advantageous (s = 0.010) novel mutant allele
in multiple populations with N = 100 @.
The allele goes to fA = 0
within 50 generation in most replicates: despite their
selection advantage, only two go to fA
= 1. Note that this stochastic
result is slightly greater than the deterministic numerical
expectation for selectively neutral alleles at initial f(A)
= 2/200 = 0.01. Note also that one population drifts
to f(A) = 0.4 before loss: the expected deterministic
trajectory is insufficient to overcome stochastic genetic
drift in a small population.
Text material © 2021 by Steven M. Carr