TABLE 3

Multilocus simulation of selective sweeps (60 loci under directional selection)

rUP(Ω)a Φ ts b eE1[e]cE2[e]d
A. Uniform selection coefficients across loci (s = 0.1)
10–22 × 10–80.850.173168.5382136833730
10–32 × 10–80.400.165171.1894.2772.2836.0
10–52 × 10–80.650.169175.2303.0263.2281.0
10–52 × 10–80.680.166187.5238.7223.9243.8
05 × 10–90.920.169188.2836.9776.6824.9
010–80.830.166197.2459.3421.0457.5
02 × 10–80.680.151200.2254.3219.8261.7
03.5 × 10–80.510.139210.5148.5128.0165.8
05 × 10–80.380.121226.6114.890.3133.8
rus Φ stss b Φ wtsw b eE1[e]cE2[e]d
B. Unequal selection coefficients and mutation rates (ss = 0.16, sw = 0.08, uw = 2us)
10–22 × 10–80.265112.80.140203.4316129492997
10–32 × 10–80.262114.90.142208.5533.6468.5486.9
10–42 × 10–80.246120.00.129220.8177.3168.9189.9
10–52 × 10–80.253128.30.113235.1155.2144.7171.1
05 × 10–90.253137.40.147215.8542.2523.9543.3
010–80.259126.80.119236.4292.3276.4314.4
02 × 10–80.222134.30.102234.0182.4142.2188.6
03 × 10–80.233140.60.091220.4107.695.7130.5
04 × 10–80.229141.80.078240.597.7472.1106.1

Results are based on 500 replicates for each parameter set. For all simulations, N = 5000, t1 = 1000, and t2 = 1000.

  • a Probability that two gene lineages experience only nonoverlapping selective sweeps before they find a common ancestor (Equation 15).

  • b Mean number of generations until fixation of the beneficial allele. tss and tsw are the fixation times for strong and weak beneficial alleles, respectively.

  • c Expected value of e from Equation 6 using (A) Φ = 1 – e–2s and (B) Φs = 1 – e–2ss and Φw = 1 – e–2sw.

  • d Expected value of e from Equation 6 using the observed values of Φ.