AUSTRALOPITHICUS Anonymous (c. 4,000,000 BCE - c. 2,700,000 BCE): Lucy has been reconstructed in this model. She was approximately 3 1/2 tall and is considered to demonstrate the upright posture that was later used by Homo Sapiens. Lucy was discovered in 1974 in the Afar Depression by Donald C. Johanson and was named after the Beatles song "Lucy in the Sky with Diamonds."