Despite a statistically significant separation in this multivariate space, and indeed on every univariate morphological measure, most populations of H. leucophyllata grade into one another in morphological space rather than showing obvious gaps.
These studies are based on the premise that the structure of phenotypic and genetic variance/covariance among multiple traits in a population can slow evolution towards optimally adapted phenotypes, depending on where this new optimum is located in multivariate space, and on the magnitude and direction of selection.
Thorough characterization of this multivariate space is difficult and costly, and finite developmental resources should be allocated using a modern science and risk-based approach.
Despite known species idiosyncrasies, our model is evidently tracking barrier traits that exert effects (Table 1) across taxa, since barriers involved in ring diversification in salamander and tree taxa are near one another in multivariate space (points 1 and 2, Figure 3A), and all individual barriers that comprise composite bird barriers also cluster (points 3 to 7, Figure 3A).
From the analysis of Figure 2(b), we can see that glucose characterizes t0 samples; lactate describes the multivariate space where samples t12 and t18 lie, and hypoxanthine, myo-inositol, and total glutathione (in its reduced, GSH, and oxidized, GSSG, forms) describe the region of t18 and t24 samples.
Our purpose was less focused on delimiting species (although we do make some recommendations) than on observing the distribution and congruence of clusters of individuals in multivariate space [sensu [ 10, 39], and discerning how changes in the way we view species affects our interpretation of the rates and significance of introgressive hybridization.
Indices I1 to I4 use multivariate space to estimate niche breadth and relative position.
Actually, PLS-DA is a special form of PLS modeling and focuses on finding the variables and directions in multivariate space, which discriminates the known classes in the training set.
Mahanalobis distances measure distance in multivariate space taking into account correlations among traits and are independent of the scale of the traits (Legendre and Legendre, 1998).
The five most highly ranked, and thus most cohesive in multivariate space, genetic clusters corresponded either to single morphospecies or groups of morphospecies.
The score plot depicted in Figure 3B shows the location of the LL muscle and SAT samples in the multivariate space of the first two PCs.
