in Southeast Asia as well as East Asia but is not a member of ASEAN. Likewise, a similar argument could be applied to some southern parts of Mainland China, as well as Hong Kong and Macau, may also considered as part of Southeast Asia as well as East Asia but are not members of ASEAN. History Prehistory The region was already inhabited by Homo erectus from approximately 1,500,000 years ago during the Middle Pleistocene age. Distinct Homo sapiens groups, ancestral to East-Eurasian (East Asian-related) populations, and South-Eurasian (Papuan-related) populations, reached the region by between 50,000BC to 70,000BC, with some arguing earlier. Rock art (parietal art) dating from 40,000 years ago (which is currently the world's oldest) has been discovered in the caves of Borneo. Homo floresiensis also lived in the area up until at least 50,000 years ago, after which they became extinct. During much of this time the present-day islands of western Indonesia were joined into a single landmass known as Sundaland due to lower sea levels. Ancient remains of hunter-gatherers in Maritime Southeast Asia, such as one Holocene hunter-gatherer from South Sulawesi, had ancestry from both, the South-Eurasian lineage (represented by Papuans and Aboriginal Australians), and the East-Eurasian lineage (represented by East Asians). The hunter-gatherer individual had approximately ~50% "Basal-East Asian" ancestry, and was positioned in between modern East Asians and Papuans of Oceania. The authors concluded that East Asian-related ancestry expanded from Mainland Southeast Asia into Maritime Southeast Asia much earlier than previously suggested, as early as 25,000BC, long before the expansion of Austroasiatic and Austronesian groups. Distinctive Basal-East Asian (East-Eurasian) ancestry was recently found to have originated in Mainland Southeast Asia at ~50,000BC, and expanded through multiple migration waves southwards and northwards respectively. Geneflow of East-Eurasian ancestry into Maritime Southeast Asia and Oceania could be estimated to ~25,000BC (possibly also earlier). The pre-Neolithic South-Eurasian populations of Maritime Southeast Asia were largely replaced by the expansion of various East-Eurasian populations, beginning about 50,000BC to 25,000BC years ago from Mainland Southeast Asia. The remainders, known as Negritos, form small minority groups in geographically isolated regions. Southeast Asia was dominated by East Asian-related ancestry already in 15,000BC, predating the expansion of Austroasiatic and Austronesian peoples. In the late Neolithic, the Austronesian peoples, who form the majority of the modern population in Brunei, Indonesia, East Timor, Malaysia, and the Philippines, migrated to Southeast Asia from Taiwan in the first seaborne