Fig. 2

Regucalcin evolution across the animal kingdom. Regucalcin presence is highlighted in green, absence in red and uncertainty regarding gene loss/presence in light blue. Gene duplications affecting a single species of a genus are marked with a *, while those which affected two or more species from the same genus are marked with a #. The number of species present in the final dataset and total number of species analysed for each taxonomic group, respectively, are shown within brackets. The identified gene duplicates are marked with letters H, S, C, T and R. Taxonomic groups are represented in different colours and labelled next to the cladogram. The known vertebrate Whole Genome Duplication (WGD) events are represented by orange circles, and the Teleost, Salmonidae and Cyprinidae specific WGDs are represented by blue circles, on top of the branches. The dashed branches represent taxonomic groups with uncertain position in the cladogram. The cladogram topology is depicted as in the Tree of Life web project [87]