In Ankole, the Hima people who live on livestock and the Iru people who live on agriculture live together; in Arizona, the Navajo people used to hunt and gather for their livelihoods, but now they mainly live on livestock. The Hoppies are neighbors; the former southeastern coast of Australia was home to indigenous people who hunted and looted food, but now they live in Europe engaged in agriculture, animal husbandry and industry. Is the author enumerating these facts to illustrate? ['The environment forces people to accept a certain lifestyle.', 'People have strong adaptability to the natural environment.', 'It is entirely possible for different cultural groups to live in harmony.', 'Geographical environment is not a determinant of human production.']