Fig. 4 in New evidence on brain-endocranial cavity relationships in ornithischian dinosaurs

Fig. 4. Phylogenetic distribution of vascular valleculae in the forebrain region (bold lines) and Encephalization Quotients in Dinosauria. Valleculae occur in the clades with the relatively largest brains (i.e., the highest EQs). EQs are from Hurlburt (1996) and were calculated using the equation EQ = Mbr/(0.0155 * Mbd0.553). EQ for Hadrosaurinae (Edmontosaurus) was recalculated using an estimate that the brain occupied 60% of the endocranial cavity. Lambeosaurine EQ is approximate and assumed to be similar to hadrosaurines. Allosaurus and Tyrannosaurus EQs were recalculated using endocast volume data from Larsson et al. (2000). When information was available for more than one taxon in a clade, an average EQ is figured. Cladogram topology after Sereno (1999), Pisani et al. (2002); theropod topology from Holtz and Osmólska (2004).