Edward Burnett Tylor was an English anthropologist who is best known for developing the theory of cultural evolution. He believed that all human societies go through stages of cultural evolution, which means that they become more complex as time passes. Tylor argued that cultures start off with a primitive and general way of life and then slowly become more specialized and organized over time. He called this idea "the survival of the fittest" and this was a major foundation for the development of the field of anthropology. Tylor also studied how cultures change, how religion was related to society, and how different societies think about the natural world. He wrote many books and articles about his theories, and these works are still studied today by anthropologists.