Figure 1.
An example of four pairs of hypothetical communities and types of phylogenetic beta diversity.
The species in a single community have the same color boxes. Species that are in neither community are left blank. All branch lengths are set to one and all species are scored as present or absent in this simplified example. It is important to note that in each of the four scenarios there is a complete turnover of species between the two communities, but the degree of phylogenetic beta diversity varies. Scenario A indicates species in the blue community are closely related to one another, but distantly related to the species in the orange community. This is an example of ‘basal’ phylogenetic turnover. Scenario B also indicates species in the blue community are closely related to one another, but distantly related to the species in the orange community. The main difference in that Scenario B has a much lower level of ‘basal’ phylogenetic beta diversity than that in Scenario A. Scenario C indicates locally phylogenetically overdispersed communities that have little phylogenetic beta diversity. Scenario D also indicates local phylogenetic overdispersion and low phylogenetic beta diversity. In both scenarios phylogenetic beta diversity measured using a nearest neighbor metric will be lower than when measured using a pairwise metric that considers the basal portion of the phylogeny and this effect will be maximized in Scenario C.
Table 1.
Calculated values for the four scenarios provided in Figure 1 using the six presence-absence weighted metrics used in the article.
Table 2.
The results of Mantel tests used to determine the correlation between community beta diversity metrics and geographic, altitudinal or precipitation differences.
Figure 2.
The relationship between phylogenetic signal in trait data (x-axis) and the relationship between the phylogenetic and functional beta diversity of communities (y-axis).
Larger K values indicate more phylogenetic signal in trait data and higher y-axis values indicate that the phylogenetic beta diversity of the tree plots is more correlated with the functional beta diversity.
Table 3.
A correlation analysis of different metrics of species and phylogenetic community dissimilarity.
Table 4.
Results of a principal components analysis of the eight phylogenetic beta diversity metrics used in this study.