An early hominid, Homo erectus, depicted in this diorama from the American Museum of Natural History's Hall of Human Biology and Evolution, lived nearly 2 million years ago in the eastern Rift Valley of Africa.
The 1.8 million-year-old skull is the most complete hominid skull ever found. The idea that there were several different human species walking the Earth two million years ago has been dealt a blow. Instead, scientists say early human fossils found in Africa and Eurasia may have been part of the same species. Continue story -