 As these people are often considered to be "stewards" of their environments, loss of language diversity means a disappearance of traditional ecological knowledge (TEK), an important factor in the conservation of biodiversity.Awareness about the balance between biological and cultural diversity has been increasing for a few decades.At the first international congress on ethnobiology in 1988, scientists met with indigenous peoples to discuss ways to better manage the use of natural resources and protect vulnerable communities around the world.