Morphometrics and multi-landmark depth analysis of the proximal hallucal metatarsal articular surface in hominoid

Three dimensional morphometrics and analysis of surface depths and breadths are used to compare the proximal articular surface of the first metatarsal among and between Homo sapiens, Pan troglodytes, Gorilla, Hylobates, and Pongo. Casts of the fossils AL 333-54, STX 5017 and OH 8 are analyzed in light of the data gathered. Significant differences in morphology exist between these species; the most extreme morphologies exhibited are in Homo and Hylobates. While the OH 8 articular surface is essentially indistinguishable from Homo sapiens, AL 333-54 and STX 5017 show a mosaic of human-like and ape-like traits, which indicates the retention of the ability to abduct and rotate the hallux. The cast of AL 333-54 shows many similarities to Gorilla, while demonstrating many changes in line with Homo . The cast of STX 5017 retains a surface morphology much like Gorilla and Pan, with fewer similarities to Homo compared to AL 333-54.