Drift & Fixation of rare alleles with strong selective advantage in finite populations
(N = 100, f(B0) = 0.005, W0 = W1 = 0.9, W2 = 1.0)
[left]
From a single initial allele (f(B) =
1/200 = 0.005 in N = 100 @) [left],
almost all populations go to f(B) = 0 within
20 generations, despite the selective advantage of the BB
genotype. Five populations, once they reach a threshold
of f(B) ~ 0.1, reach f(B) = 1
within 150 generations. [right] For slightly strong
selective advantage, compare the trajectories and range of
the stochastic results with the deterministic expectation
[black curve].
Text material © 2025 by Steven M. Carr