These results are consistent with the relationships between the altitude and the q for the TESS groups, which was tested by performing a simple regression analysis; indeed this relationship was highly significant (P < 0.0001) for the TESS clusters T1, T2, T5 and T6 (R 2 = 0.25, 0.14, 0.10, 0.22 respectively), significant (P = 0.05) for T3, but not significant for T4 (P = 0.08).
The number of alleles ( n a ) and the allelic richness ( R S ) of the low altitude class (<2,300 m a.s.l.: n a = 39 and R S = 5.57) were lower than those of the intermediate altitude class (2,300-2,800 m a.s.l.: n a = 50 and R S = 7.10; difference marginally non-significant, P = 0.06, Wilcoxon signed-paired rank test, after Bonferroni correction) and of the high altitude class (>2800 m a.s.l.: n a = 57, P = 0.06, and R S = 7.40, P = 0.09).