FIGURE 1 in Phylogeny of iguanodontian dinosaurs and the evolution of quadrupedality

FIGURE 1. Simplified phylogeny showing the current understanding of ornithischian relationships, based on Butler et al. (2008). Silhouettes from Phylopic.org. Daspletosaurus by Tasman Dixon, Brachiosaurus by Michael P. Taylor, Lambeosaurus by Craig Dylke (all public domain). Triceratops by Raven Amos, Heterodontosaurus by Jaime Headden, Stegosaurus by Andrew A. Farke, Hypsilophodon by Mathew Wedel (https://creativecommons.org/licenses/by/3.0/). Stegoceras by Caleb M. Brown (http://creativecommons.org/licenses/by-sa/3.0/).