Although Darwin＇s natural selection theory reveals the competitive evolution of the organisms, it can not explain the altruistic and cooperative behavior of individual organisms. In the second half of the 20th century, with biologists＇ researches on altruism and cooperation in animal behavior, it gradually reveals the relationship of biological organism＇s egoism and altruism, the relationship of competitive evolution and cooperative evolution. The researches have improved the natural selection theory, and have promote...
