TABLE 2.
Means and 95% confidence intervals for data sets simulated in Serial SIMCOAL
| Mainland
|
Island
|
|||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| μ | Ne | r | S | π | D | Ne | r | S | π | D |
| 7 × 10−7 | 7 × 106 | 0 | 34.25 (31.94, 36.57) | 0.029* (0.026, 0.032) | 0.01* (−0.16, 0.19) | 25,000 | 0 | 0.12* (0.05, 0.20) | 5.81 × 10−5* (9.12 × 10−6, 1.07 × 10−4) | 0.4* (−0.25, 1.09) |
| 7 ×10−7 | 7 × 106 | 1 × 10−8 | 27.77* (25.94, 29.59) | 0.020* (0.018, 0.023) | −0.45* (−0.70, −0.20) | 25,000 | 1 × 10−8 | 0.02* (−0.02, 0.07) | 3.17 × 10* (−3.23 × 10−5, 9.57 × 10−5) | 0.054a |
| 7 ×10−7 | 7 × 106 | 1 × 10−6 | 15.90 (14.81, 16.98) | 0.010 (0.009, 0.011) | −0.86* (−0.98, −0.73) | 25,000 | 1 × 10−6 | 0.13* (0.07, 0.20) | 1.32 × 10−4* (5.62 × 10−5, 2.08 × 10−4) | −0.24* (−0.84, 0.35) |
| 7 × 10−7 | 7 × 106 | 1 × 10−6 | 15.46* (14.52, 16.44) | 0.010 (.009, 011) | −082* (−0.97, −0.67) | 100,000 | 1 × 10−6 | 0.41 (0.28, 0.54) | 4.03 × 10−4* (2.57 × 10−4, 5.49 × 10−4) | −0.32* (−0.63, −0.01) |
| 1 × 10−6 | 7 × 106 | 2 × 10−6 | 14.77* (13.94, 15.60) | 0.008 (0.072, 0.084) | −1.19 (−1.30, −1.09) | 100,000 | 2 × 10−6 | 0.63 (0.47, 0.79) | 6.29 × 10−4* (4.60 × 10−4, 7.98 × 10−4) | −0.22* (−0.47, 0.03) |
| 2 × 10−6 | 7 × 106 | 2 × 10−6 | 30.20* (29.02, 31.38) | 0.016 (0.015, 0.17) | −1.29 (−1.38, −1.21) | 100,000 | 2 × 10−6 | 1.230 (0.98, 1.48) | 0.001 (9.41 × 10−4, 0.01) | −0.26 (−0.50, −0.02) |
| Empirical values (95% CI): | 18.87 (13.40, 24.33) | 0.010 (0.074, 0.13) | −1.18 (−1.42, −0.94) | 2.10 (0.74, 3.64) | 0.002 (5.68 × 10−4, 2.78 × 10−3) | −0.65 (−1.44, 0.13) | ||||
Mutation rate per locus (μ), effective population sizes (Ne), and population growth rate (r) were varied for the mainland and island populations. A model with no growth (r = 0) for the mainland population produced summary statistics (S, number of segregating sites; π, nucleotide diversity; and Tajima's D) that were significantly different from empirical distributions (*Kolmogorov–Smirnov test, P < 0.05). Although none of the scenarios we tested were perfectly consistent with our data (K–S test, P > 0.05 across all parameters and populations), models incorporating population growth, higher mutation rates, and Ne = 100,000 for the island population values yielded summary statistics comparable with the observed data.
Estimates of nucleotide diversity (π) island population were often 0, making Tajima's D undefined. Averages of Tajima's D for the island population therefore represent only cases where π > 0. Where <5 simulations of 100 yielded π > 0, we did not calculate confidence intervals.