Table 5.
Mean values of Tajima’s D and Fay and Wu’s H for the three Picea species observed in the analysed data and expected under a standard neutral model (SNM) and a bottleneck model followed by population expansion (BottExp)
| P. glauca | P. mariana | P. abies | ||||
|---|---|---|---|---|---|---|
| Mean Tajima’s D | Mean Fay and Wu’s H | Mean Tajima’s D | Mean Fay and Wu’s H | Mean Tajima’s D | Mean Fay and Wu’s H | |
| Observed | −0.88 | −3.20 | −0.90 | −2.52 | −1.49 | −6.14 |
| SNM | −0.02 (P = 0) | 0.01 (P = 0.02) | −0.02 (P = 0.001) | 0.04 (P = 0.02) | −0.01 (P = 0) | 0.04 (P = 0) |
| BottExpa | −0.92 (P = 0.55) | −6.89 (P = 0.44) | −0.76 (P = 0.52) | −5.50 (P = 0.50) | −0.75 (P = 0.23) | −5.25 (P = 0.33) |
A model is considered to fit empirical data if the P values of all the parameters considered (mean and variances of D and H) are higher than 0.05 (no significant difference)
aThe bottleneck model that best fit the observed data for each of the three species occurred during the LGM around 25,000 years ago and ended about 17,000 years ago when populations started expanding. Other near-best models suggested that the expansion phase might have been delayed to the Holocene for P. glauca and P. abies (see “Results”)