Phylogenetic analysis of RTKs. Trks, Trkls, NRKs and RORs are analyzed together with Drosophila DTrk (DmDTrk) as an outgroup. A: Phylogenetic tree based on full length sequences: A BI derived tree topology is shown as well as support values for the nodes computed by BI (pp: posterior probability directly above the branches) and ML (ML bootstrap values directly below the branches). B: Phylogenetic tree based on sequences encoding the tyrosine kinase domains only. The topology and support values are depicted in the same way as in A. Human (Homo sapiens), Chicken (Gallus gallus), Zebrafish (Danio rerio), Amphioxus (Branchiostoma floridae), Sea urchin (Strongylocentrotus purpuratus), Lottia (Lottia gigantean), Aplysia (Aplysia californica), Dappu-(Daphnia pulex), Capitella (Capitella Sp. I), Honey Bee (Apis mellifera), Pea Aphid (Acyrthosiphon pisum), Jewel wasp (Nasonia vitripennis), Drosophila (Drosophila melanogaster).