We used SYNERGY [27, 28] to reconstruct the phylogeny of proteins across all 31 organisms, define sets of orthologs ("orthogroups"), and construct a phylogenetic tree of the genomes (Figure 1 ). An orthogroup is defined as the set of genes descended from a single common ancestral gene in the last common ancestor of the species under consideration [28] , containing both orthologs and possibly paralogs (Methods). At each node in the phylogenetic tree, we tabulated orthogroup appearances, duplications, and losses ( Figure 2 ). Figure 2 gives an overview of the evolution of gene families within these species. Full listings of the events tabulated in Figure 2 , as well as additional information about each orthogroup, can be found on the Supplementary Information website: