Extended Data Fig. 3: Comparative mandibular third premolar morphology and dimensions.

a, P₃ occlusal morphology of eastern African hominins. A.L. 128-23, A.L. 333w-1 (mirrored), KNM-ER 5431, A.L. 437-2, OMO 33-73-5496, and LD 302-23. The crown of LD 302-23 measures 10.5 mm MD x 11.5 mm BL (est.). Mesial is oriented up and lingual is oriented to the right. Scale bar in centimetres; images are to scale. b, Bivariate plot of P₃ crown dimensions. The LD 302-23 P₃ (magenta star) falls near the upper range of Homo and well within Australopithecus. Authors’ data supplemented by references in Extended Data Table 1. Although LD 302-23 is large for a Homo P₃, our interpretation of the occlusal morphology is more consistent with assignment to this genus. c, P₃ (MD/BL ratio) shape variation. LD 302-23 falls in the middle range of Australopithecus and lower in the range of Homo, although these patterns show overlap. d, P₃ variation in area (mm²). LD 302-23 falls in the upper ranges of Australopithecus and Homo but is small compared to P. boisei.