Fig. 4.
Simplified gene tree of the Nav family showing inferred ancestral states of the pore motifs. The gene duplication leading to the bilaterian Nav 1 and Nav 2 clades is noted, as are the points where we reconstruct fixation of lysines (K) in pore loops. Taxonomic information and information about the nervous system is also given. The Nematostella β and Trichoplax β genes have been left out for simplicity, but their addition would not change the proposed ancestral states. Pore states for both Mnemiopsis genes are shown because neither has a complete pore motif.