Figure 1. Evolution of influenza virus in New World bats.
(a) Phylogenetic relationships of influenza A viruses sampled from bats (red branches) and other animals (‘non-bat’, black branches) based on the amino acid sequences of each gene segment. (b) The maximum amino acid distances are shown within and between the bat and non-bat sequences, and colored accordingly. These levels of diversity also effectively act as a scale-bar for the trees shown above.