Role of ecological characteristics
Both pairwise intraspecific geographical and genetic distances were
plotted in subsets of ecological properties (see above). Subsequently,
sampling variables (i.e., the number of sampled localities, the number
of sampled specimens and the mean geographic distance among sampled
individuals per species) were plotted against test statistics and
significance to investigate the degree of their correlation. To check
for the role of sampling design on the meta-analyses through plot
choice, we compared statistics and significance scores of every species
against the other variables with the number of individuals examined per
species, the number of sampled localities and the mean geographic
distance among sampled individuals per species.
To detect potential population genetic “anomalies” or “regularities”
referable to ecological dynamics, we produced boxplots on all data and
on subsets of data, observing the variance in the mean values of
statistic and significance scores obtained as Mantel/NMDS/PCA output. We
were aware that significance in major part is also dependent from the
amount of intraspecific sampling of each species and the strength of the
relation.