Indigenous peoples everywhere are under threat today. One indicator of the loss of human cultural diversity is the loss of language. Linguists predict that almost half the world´s 6000 languages will die out in the next century. When they do, these cultures will also take with them traditional knowledge that is invaluable.
The world´s 250 million indigenous peoples live in about 70 countries and are marginalised wherever they are. They are also known as First Peoples, Indians, Natives, Aborigines, Nomads, Tribal?, First Nations, Minority Nationalities (China) and Small Peoples (Russia). But they are not just the first-comers to a land. The term is usually used more broadly, to include other marginalised groups such as the nomadic peoples of Africa. British anthropologist Andrew Gray says that, compared with the number of national state cultures, indigenous peoples constitute 90 to 95 per cent of global cultural diversity and "therefore represent the diversity of human existence, even though they constitute a numerical minority".
Previously, the main threat to human cultural diversity was extermination, which led, for example, to a fall in the Aboriginal population of Australia from 500 000 to 100 000 in the century after the arrival of Europeans. Since 1900, in Brazil alone, more than 90 indigenous groups have disappeared; 26 of those tribes were killed or scattered in the past decade. The rate of extinction has accelerated as a result of forest destruction. Today, assimilation is the main threat to cultural diversity.
Examples abound of the value of indigenous knowledge to modem agriculture and medicine. Forest dwellers in Papua New Guinea have for years cultivated the hardy and protein-rich winged bean (Psychocarpus tetragonohbus) which also enriches the soil by its ability to fix nitrogen.