Uncontacted Indigenous peoples reject contact with outsiders, as an active and ongoing choice. Survival International has calculated that there are 196 uncontacted groups worldwide; some of these are entire peoples who are uncontacted – such as the Sentinelese in India. Some uncontacted groups – such as the Ayoreo Totobiegosode in the Paraguayan Chaco or the Amahuaca in Peru – are sub-groups of bigger tribes with whom they share a language and often a territory. All are aware of the outside world, and reject it. They are self-sufficient and resilient. They live independently in forests, sometimes on islands. They resist intrusion, and thrive when their rights are respected. Uncontacted peoples may encounter outsiders sporadically, or not at all. They are aware of neighboring Indigenous peoples, who may be closely or distantly related. The uncontacted Hongana Manyawa in Indonesia have family members who have left the forest, mostly under duress. The uncontacted Pirititi occasionally encounter their contacted Kinja neighbors in the Brazilian Amazon. The Massaco, also in Brazil, were for decades known only by traces in the forest, including booby traps sharpened with rodents' teeth and placed on their hunting trails to warn off outsiders. Uncontacted peoples’ rejection of contact is often rooted in memories of devastating past contact and invasion, which brought violence, epidemics and death. Their denial of contact is a clear expression of their autonomy and self-determination.