Fig. 2.
From: The round goby genome provides insights into mechanisms that may facilitate biological invasions
Phylogenetic tree of vertebrate opsin gene sequences. Maximum likelihood phylogenetic tree based on the cone and rod visual opsins and using VA opsins and pinopsins as outgroup. The round goby genome contains two LWS gene copies, which seem to be the results of an ancient gene duplication event, and two more recently duplicated RH2 gene copies. Round goby is indicated in orange. Red opsin branches are indicated in red; green opsin branches are indicated in green. Non-teleost species and the outgroup (VA opsins and pinopsins) are indicated in gray. Gray boxes highlight Gobiidae. See Additional file 2: Figure S1 for a tree including expanded SWS1, SWS2, and RH1 branches and Additional file 3: Figure S2 for an exon-based tree