Evidence for increased hominid diversity in the Early to Middle Pleistocene of Indonesia

International audienceSince the first discovery of Pithecanthropus (Homo) erectus by E. Dubois at Trinil in 1891, over 200 hominid dentognathic remains have been collected from the Early-Middle Pleistocene deposits of Java, Indonesia, forming the largest palaeoanthropological collection in Southeast Asia. Most of these fossils are currently attributed to H. erectus. However, because of the substantial morphological and metric variation in the Indonesian assemblage, some robust specimens, such as the partial mandibles Sangiran 5 and Sangiran 6a, were formerly variably allocated to other taxa (Meganthropus palaeojavanicus, Pithecanthropus dubius, Pongo sp.). To resolve the taxonomic uncertainty surrounding these and other contentious Indonesian hominid specimens, we used Occlusal Fingerprint Analysis to reconstruct their chewing kinematics, and also used various morphometric approaches based on microtomography to examine internal dental structures. Our results confirm the presence of Meganthropus as a Pleistocene Indonesian hominid distinct from Pongo, Gigantopithecus and Homo, and further reveal tha