FIGURE 1. Simplified cladogram showing the relationships of the three main lineages of dinosaurs with focus on Sauropodomorpha. Letters A - F are related to clades treated in the main text. The assumed ages for the taxa of the tree are represented by rectangles thicker than other branches. Cladogenetic events (dichotomies) are not calibrated against geological time. Ornithischia is represented by the following taxa: Pisanosaurus, Heterodontosauridae, Eocursor, Thyreophora, Neornithischia. Theropoda is represented by the following taxa: Tawa, coelophysoids, Ceratosauria, Tetanurae. All other taxa represent Sauropodomorpha (here following the definition of Galton and Upchurch, 2004). Sauropoda (here following the definition of Salgado et al., 1997) is represented by Vulcanodon, Tazoudasaurus, Spinophorosaurus, Neosauropoda.

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FIGURE 2. Simplified version of the cladogram of Figure 1 showing the relationships of the three main lineages of dinosaurs with focus on Sauropodomorpha. ‘Sauropodomorpha A’ and ‘Sauropodomorpha B’ represent two hypothetical taxa that are more closely related to Saturnalia than to Sauropoda. Ornithischia is represented by a single terminal taxon and Theropoda is represented by the living bird Gallus gallus.

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FIGURE 3. Hypothetical data matrix and the most parsimonious tree obtained when it is analysed using parsimony.

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