Indigenous Australians are the Aboriginal and Torres Strait Islander people of Australia, descended from groups that existed in Australia and surrounding islands prior to European colonization. The earliest definite human remains found in Australia are those of Mungo Man, which have been dated at about 40,000 years old, although the time of arrival of the first Indigenous Australians is a matter of debate among researchers, with estimates including thermoluminescence dating to between 61,000 and 52,000 years ago, as well as a suggestion of up to 125,000 years ago.
There is great diversity among different Indigenous communities and societies in Australia, each with its own mixture of cultures, customs and languages. In present-day Australia these groups are further divided into local communities. At the time of initial European settlement, over 250 languages were spoken; it is currently estimated that 120 to 145 of these remain in use, but only 13 of these are not considered endangered.
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