Phylogenetic tree of rhodopsins from Amoebozoa, algae, bacteria and fungi. The tree was constructed by the neighbor-joining method based on the amino acid sequence of the rhodopsin domain using MEGA version 5 . The scale bar indicates the number of substitutions per site. Detailed rhodopsin information is listed in Table S3.6.1 in Additional file 1.
Clarke et al. Genome Biology 2013 14:R11 doi:10.1186/gb-2013-14-2-r11