Australopithecus afarensis' Hip Bone Indicates She Could ...

When Lucy’s hundreds of fragments were assembled, she turned out to be a female of a new species, Australopithecus afarensis, dating back 3.2 million years. She was between 20 and 30 years old, 3.5feet tall, weighing a scant 60 pounds, and possibly afflicted with arthritis. But most important, she walked on two legs. How can we tell? From the way that the femur (thighbone) connects to the pelvis at one end and to the knee at its other. In a bipedally walking primate like ourselves, the fem...