Johanson, Donald Carl (1943-...), an American anthropologist, is an authority on human origins. Johanson is also one of the world's most successful fossil hunters. In 1974, an expedition led by Johanson at Hadar, Ethiopia, discovered the fossilized remains of what is now commonly regarded as one of the earliest types of humanlike creatures that walked fully upright. The fossils, from a creature nicknamed "Lucy," are between 3 million and 3,600,000 years old. They belong to a species classified as Australopithecus afarensis (see Australopithecus).