multiple optima model is proposed to explain this contradictory result. Multiple optima model allows more than one optimal scenario and is valid to explain high time-devoting lithic technology (i.e., pre-processing of lithic) and more residential mobility strategy in the same time. Genetic links to ancient and modern East and Southeast Asian populations , only two ancient DNA samples have been extracted from individuals excavated in Hoabinhian contexts: one specimen from in Pha Faen in Bolikhamxay Province, Laos (7888 ± 40 BP) and one from Gua Cha in Ulu Kelantan, Malaysia (4319 ± 64 BP). While the Upper Paleolithic origins of this 'Hoabinhian ancestry' represented by the two samples are unknown, Hoabinhian ancestry has been found to be related to the main 'East Asian' ancestry component found in most modern East and Southeast Asians, although deeply diverged from it. Among present-day populations, the Andamanese Onge and Jarawa, and the Semang (also known as "Malaysian Negritos") and Maniq in the interior of the Malay Peninsula are genetically closest to the sampled ancient Hoabinhian individuals. The emergence of the Neolithic in Southeast Asia went along with a population shift caused by migrations from southern China. Neolithic Mainland Southeast Asian samples predominantly have East Asian ancestry related to ancient populations from southern China, but many of these samples also display admixture with Hoabinhian ancestry or Hoabinhian-related ancestry to a smaller degree. In modern populations, this admixture of East Asian and Hoabinhian (or Hoabinhian-related) ancestry is most strongly associated with Austroasiatic-speaking groups, and can also be reproduced in models where Onge samples are taken as proxies for Hoabinhian ancestry. See also Con Moong Cave An Son References Sources Literature Colani M. (1927) L'âge de la pierre dans la province de Hoa Binh. Mémoires du Service Géologique de l'Indochine 13 Flannery, KV. (1973) The origins of agriculture. Annual Review of Anthropology 2: 271-310 Forestier H, Zeitoun V, Winayalai C and Métais C (2013). The open-air site of Huai Hin (Northwestern Thailand): Chronological perspectives for the Hoabinhian. Comptes Rendus Palevol 12(1) Gorman C. (1969) Hoabinhian: A pebble tool complex with early plant associations in Southeast Asia. Science 163: 671-3 Gorman C. (1970) Excavations at Spirit Cave, North Thailand: Some interim interpretations. Asian Perspectives 13: 79-107 Gorman C. (1971) The Hoabinhian and After: Subsistence Patterns in Southeast Asia during the Late Pleistocene and Early Recent Periods. World Archaeology 2: 300-20 Matthews JM. (1964) The Hoabinhian in Southeast Asia