FIGURE 1. A in Heterodonty in Tyrannosaurus rex: Implications for the taxonomic and systematic utility of theropod dentitions

FIGURE 1. A, idealized human dental arcade, in palatal view, showing mesial, distal, labial, and lingual directions (modified from Smith and Dodson, 2003). LM1, left upper first molar. B, photo traces of AMNH 5027 Lmx7–8 (bones are schematic), showing mesiodistal orientations of crown long axes (points A–D were defined by Smith et al., 2005). C, photo trace of the premaxilla of AMNH 5027 (teeth are schematic) in palatal view showing labiolingual orientations of the crown long axes. D, Saurornitholestes Sues, 1978, crown in lateral view showing crown height (CH, measured from the apex to the base of the enamel (̴between points G and B)); crown base length (CBL, measured along the mesiodistal axis of the crown at the base of the enamel, ̴between points A and B); apical length (AL, measured between points A and G); crown angle (CA, angle GAB); mesial apical (MA), mesial mid-crown (MC), and mesial basal (MB) denticle densities (measured along the length of the mesial carina); distal apical (DA), distal mid-crown (DC), and distal basal (DB) denticle densities (measured along the length of the distal carina). E, the crown in D in basal view showing CBL and crown base width (CBW, measured perpendicular to CBL). Crown in D redrawn from Currie et al., (1990). Figure concept after Smith et al. (2005).