Perhaps the world's most famous early human ancestor, the 3.2-million-year-old ape "Lucy" was the first Australopithecus afarensis skeleton ever found, though her remains are only about 40 percent complete (photo of Lucy's bones).

Discovered in 1974 by paleontologist Donald C. Johanson in Hadar, Ethiopia, A. afarensis was for about 20 years the earliest known human ancestor species (Africa map).

With a mixture of ape and human features—including long dangling arms but pelvic, spine, foot, and leg bones suited to walking upright—slender Lucy stood three and a half feet (107 centimeters) tall.

Recreations based on other A. afarensis skulls later found nearby reveal an apelike head with a low and heavy forehead, widely curving cheekbones, and a jutting jaw—as well as a