Species to which all modern human beings belong. The oldest known fossil remains date to c. 120,000 years agoor much earlier (c. 400,000 years ago) if evidence of certain archaic varieties is included. Homo sapiens is distinguished from earlier hominin species by characteristics and habits such as bipedal stance and gait, brain capacity averaging about 1,350 cc, high forehead, small teeth and jaw, defined chin, construction and use of tools, and ability to use symbols. Most scholars believe that modern humans developed in Africa c. 150,000 years ago and spread to the Middle East c. 100,000 years ago and to other parts of Eurasia c. 40,000–50,000 years ago (this is known as the single-origin model). Others contend that modern humans developed from various regional populations of archaic H. sapiens or even other species of Homo in Eurasia beginning c. 250,000 years ago (the multiregional model). In the first model the genetic differences that exist between the peoples of the world would not be very old; in the second model they would be significantly older. In any case, by c. 11,000 BC modern H. sapiens had peopled virtually the entire globe. See alsoCro-Magnon; culture; human evolution; Neanderthal.