The timeline of human evolution outlines the major events in the evelopment of human species, and the evolution of humans' ancestors. It includes a brief explanation of some animals, species or genera, which are possible ancestors of Homo sapiens sapiens. It begins with the origin of life and presents a possible line of descendants that led to humans. This timeline is based on studies from paleontology, developmental biology, morphology and from anatomical and genetic data. The study of human evolution is a major component of anthropology.