Figure 1

Identification of pairs of parsimony-informative coevolving amino acid sites. The figure represents a multiple sequences alignments with the phylogenetic relationships of its constituent sequences. The phylogenetic tree is asymmetric due to the accelerated rates of evolution of one of the sequences (long branch). As a result, most of the evolutionary signal (amino acid variability) in the multiple protein sequence alignment (right hand) is due to amino acid differences at sites contributed by the accelerated sequence. Parsimony-informative coevolving sites (those sites showing at least two different amino acid states with each one represented by at least one sequence of the alignment) are shown, and the variability in their states is colour coded. Non-parsimony informative coevolving sites are also highlighted as example of phylogenetic coevolution.