Homo erectus (Peking man); Date: 780,000-400,000 BP; Location: Zhoukoudian, China. This composite skull combines several skulls from the same site, first named Sinanthropus pekingensis but later attributed to Homo erectus. The original fossils vanished while being shipped to the United States for safety during World War II, but scientists still have high-quality casts and descriptions to work with.