Fig. 2: Calibrated and dated vertebrate evolution.

Time-calibrated rooted phylogeny of vertebrates and two non-vertebrate species with 95% credibility intervals for clade divergence times indicated by red bars on nodes. The phylogenetic tree was obtained with Bayesian inference (Extended Data Fig. 2a) and all nodes were recovered with a posterior probability of 1. Numbers of gene family gains (green, novel homology group (HG); blue, novel core HG) and losses (red) are indicated in selected nodes (see text). Dated WGD events, including 1R, 2R and cyclostome-specific event (CR) described in this study, are indicated with coloured rectangles. The hagfish position is highlighted with a thickened line and bold font. Geological periods are colour-coded at the bottom: Ediac., Ediacaran; Cambr., Cambrian; Ordo., Ordovician; Sil., Silurian; Devon., Devonian; Carbonif., Carboniferous; Perm., Permian; Palg., Paleogene; Ng., Neogene. Animal illustrations kindly provided by Tamara de Dios Fernández; human, zebrafish, lamprey and hagfish illustrations reproduced with permission from ref. ¹³³.