The results of phylogenetic signal test based on Blomberg’s K show
values in PC1 and PC2 are less than 1, best-fitted to WN model, which
suggests that PC1 and PC2 dimension climate changes independence of
phylogenetic relationships (data with no covariance structure among
clades); but more than 1 in PC3, PC4 and PC5 indicate PC3, PC4 and PC5
dimension changes have closely related phylogenetic relationships (Table
4). The comparisons of model fit based on the AICc value and AICc
weights (ω) indicate that the WN model is preferred in PC1 and
PC2, where climatic components change in PC1 and PC2 regardless of
shared ancestry between clades. Although niche conservatism is
maintained in some clades for PC1 and PC2 (Figure 2c and Table 4), our
tests of PC3, PC4 and PC5 fitted to a BM model, suggesting that
following a divergence event along these climate PCs, clades branches
may be subject to these variable environmental conditions, such as
promoting the evolution of different climatic tolerances, which may be
accumulated independently from ancestral ones.