they aren't "uncontacted tribes". They are voluntarily isolated tribes.

[the_future_modernes]

‘The last free people on the planet’

In small pockets around the world live isolated indigenous communities, groups that, even though they have had run-ins with their neighbours or Westerners, prefer to avoid or resist any further contact. Although we sometime call them ‘uncontacted,’ a more accurate description is probably ‘voluntarily isolated’ or ‘withdrawn’ or ‘evasive.’ Many of these groups have tragic histories of encounters with outsiders — too much ‘contact’ — where they fought to preserve their isolation and, usually, came up much worse off than their more numerous intruders.

Survival International reports that about one hundred groups around the world prefer to be left alone. They refuse to become enmeshed with their neighbours, to give up their ways of life and languages, or to find some way to earn the local currency or trade goods. All have made it abundantly clear their wishes: stay away.

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