Human evolution is that part of biological evolution concerning the emergence of humans as a distinct species. It is the subject of a broad scientific inquiry that seeks to understand and describe how this change and development occurred. The study of human evolution encompasses many scientific disciplines, most notably physical anthropology, linguistics and genetics. The term "human", in the context of human evolution, refers to the genus Homo, but studies of human evolution usually include other hominins, such as the australopithecines.