Ancestral state reconstructions to visualise the change in viral load across the host phylogeny at three temperatures.

Ancestral states are plotted as colour gradients across the tree. The colour gradient represents the change in RNA viral load; red represents the highest and green the lowest viral load at that temperature. Ancestral states were estimated using a phylogenetic mixed model that partitioned the inter-specific variance into that explained by the host phylogeny under a Brownian model of evolution (vp), and a species-specific variance component that is not explained by the phylogeny (vs).