How Teeth Can Help Us Decipher the Puzzle of Hominin Evolution in Asia

Clément Zanolli1,2*, Sofwan Noerwidi3, Jülide Kubat4,5, Xing Song6,7, Armand S. Mijares8,9, Florent Détroit10, Renaud Joannes-Boyau11, Fabrice Demeter12,13, Friedemann Schrenk5, Anne-Marie Bacon4, and Ottmar Kullmer5,14

Asia is a vast and ecologically diverse continent, which during the Pleistocene acted as a hub where several hominin taxa dispersed, met, interbred, evolved and diversified. Among them, Homo erectus, Homo neanderthalensis, Homo longi and Homo sapiens thrived on the Asian mainland (and even beyond for some of them), while Meganthropus palaeojavanicus, Homo floresiensis and H. luzonensis represent endemic forms that evolved in insular Southeast Asia. However, the phylogenetic relationships and evolutionary trajectories of these species remain unclear. Teeth are the most abundant elements representing these species, and they also happen to be among the most taxonomically diagnostic anatomical structures available in the fossil record. We extracted and analysed taxonomically and phylogenetically informative data from Asian hominin fossil dental remains and compared them with those of several other species, of Australopithecus, Paranthropus and Homo. Our results point toward a close evolutionary relationship between Australopithecus/Homo habilis and Meganthropus, implying an Early Pleistocene dispersal of another species than H. erectus from Africa to Asia. H. floresiensis and H. luzonensis most likely derived from H. erectus in insular contexts. Homo erectus also evolved on the Asian mainland during the Middle Pleistocene, sharing territories with H. longi and possibly also with early dispersed groups of H. sapiens coming from Africa or western Asia. The advanced study of teeth offers new insights to reconstruct the puzzle of human evolution in Asia.