The bipedalism of the Dmanisi hominins: pigeon-toed early Homo?

In the recent description of the hominin postcranial material from Dmanisi, Georgia, Lordkipanidze and colleagues (Lordkipanidze et al. [2007] Nature 449: 305-310) claim that the Dmanisi hominins walked with more medially oriented feet than do modern humans. They draw this functional inference from two postcranial features: a wide talar neck angle and a slight medial torsion of the tibia. However, we believe that the data provided by the authors fail to support their conclusions. Talar neck angle and tibial torsion values from the Dmanisi specimens fall comfortably within the range of modern human variation. We further submit that foot orientation cannot be reliably deduced from the tibia and talus alone.