Anthropology is the study of humans. It consists of four main sub-fields: Archaeology, Cultural Anthropology, Languages, and Paleoanthropology. Humans are the undisputed rulers of planet Earth. A human's brain is so advanced that it can manipulate virtually any environment to suit its needs, as well as create countless artifacts to improve its quality of life. Humans are capable of extraordinary compassion towards the misfortune of other members of its species, as well as countless non-human species, but are also able to cause immense devastation to the former, as well as multiple extinctions in the latter. Humans, or "Hominins," are members of the Great Apes, which include the orangutans, gorillas, chimpanzees, bonobos, and several extinct species. Like most animals, the human line would come from meager beginnings in the form of an ape with some of the most basic of human-like qualities, such as the bipedalism evidenced in the fossils of the earliest known human ancestor Sahelanthropus tchadensis of the Miocene epoch, central Africa, approximately 7 million years ago. In the millions of years to follow, the human line would continue not in a straight progression from the first species to the last, but into a multi-branched tree of several species, including the genus Australopithecus of which the famous "Lucy" specimen is a member of. From the Australopithecines would evolve another branch of the human family tree, the genus that survives today known as Homo. As the Homo genus continued to thrive, more modern human qualities would continue to evolve, such as an increased size in the brain. With a larger brain would come more advanced communication, planning, empathy, strategy, weapon and tool technology, artistry, as well as the ability to give concern to things outside of the realm of natural instinct, such as the moot question of where did we come from, and do we have a purpose outside of the natural world. With this question would come the invention of religion; the human-born concept of beliefs based on the attempt at making sense of what was then "the unknown" concerning the natural world, from which countless rituals and supernatural entities were created from the mind of mankind, and some of which still persist today. Approximately 180,000-200,000 years ago, a new species of human would evolve in Africa, the Homo sapiens. This species would eventually migrate out of Africa between 50,000-100,000 years ago, and would progressively dominate the planet wherever it went, eventually becoming the most successful mammal of all time. By around 12,000 years ago, all other species of human had become extinct, leaving only Homo sapiens to rule the world.