Fig. 3. Phylogenetic trees. Trees were calculated using amino acid sequences. Numbers at branching points are bootstrap values exceeding 500. (A) Phylogenetic tree of Pax6 proteins. Platynereis Pax6 is closest to the other lochotrophozoan Pax6 proteins described so far. (B) Phylogenetic tree of Six/Sine oculis proteins. Platynereis six1/2 clearly clusters within the Six1/Six2 subfamily. (C) Phylogenetic analysis of Atonal-related proteins shows close relationship of Platynereis ath with Drosophila atonal. (D) Clear distinction between rhabdomeric (r-) and ciliary (c-) opsis revealed by phylogenetic analysis. Platynereis opsin is a member of the r-opsins subgroup.