Fig. 8.

Phylogenetic analyses of the vertebrate ROR family shows that ROR-γ existed in the jawed vertebrate ancestor and reveals a new vertebrate ROR-β paralog not found in mammals (which we name ROR-δ). Alternative rooting strategies, using (a) a relaxed clock model, (b) fruit fly HR3 as outgroup, or (c) human RARs as outgroup, show that the root of the ROR phylogeny cannot be confidently placed. Gene level clades are collapsed in (b) and (c), but contain the same taxa as a Other details as per Fig. 3