The game traces the development of early human species from 120,000 years ago through to the near-modern era. Players take the role of Peking Man, Archaic Homo Sapiens, Cro-Magnon, Neanderthal, or Homo Floresiensis, and each attempts to develop instincts and higher cortical brain functioning, such as language traits. The populations expand and collide, and eventually consciousness, society, and culture are sought after.