The study of people’s relationships with plants, e.g. how plants are used for food, shelter, medicine, cosmetics, clothing, or weapons, as well as the religious or broader cultural significance of plants. The work of ethnobotanists has contributed to the discovery and identification of many plants used for medicinal purposes by indigenous peoples, particularly those of tropical rainforests. Commonly these plants are assessed by pharmaceutical companies as sources of potential new drugs. Many other economically useful products have been derived from ethnobotanical research. Such work entails stringent ethical obligations (see bioprospecting). Other disciplines, such as anthropology, archaeology, and sociology, also have ethnobotanical dimensions.