Several parameters were computed to estimate the genetic diversity at the population level. We estimated allelic frequencies
using Zhivotovsky's (1999) Bayesian method, with uniform prior distributions and assuming HardyeWeinberg
genotypic proportions. Genetic diversity (He) based on allele frequencies was calculated using the method of Lynch and
Milligan (1994), as implemented in the program AFLP-SURV v. 1.0 (Vekemans et al., 2002). A matrix of pairwise population
FST (the proportion of the total genetic variance contained in a subpopulation (S subscript) relative to the total genetic
variance (T subscript)) values using the FST analogue ФPT was calculated using GENALEX 6.0 (Peakall and Smouse, 2006). To
visualize the pattern of genetic clustering of individuals, we used principal coordinate analysis (PCoA; Orloci, 1978) and
plotted the results on a genetic distance matrix generated from the binary presenceeabsence matrix, as implemented in
GENALEX 6.0. We also examined patterns of population structure using the Bayesian assignment probability test in the program
STRUCTURE 2.2 (Pritchard et al., 2004)