In 1974, scientists working in Ethiopia uncovered an extraordinary female skeleton, whom they called Lucy. She was 3.2 million years old, and belonged to a new species of hominid now known as Australopithecus afarensis. Her brain was small and chimp-sized, but her hips and legs that were clearly built for upright walking—a unique blend of features which revealed that our ancestors evolved a two-legged gait before their brains became big.
Lucy has since become a household name, and it’s easy to forget that she was more than just an avatar of human evolution. She was also a person. Back when her now-famous skeleton was still wrapped by flesh and skin, she was walking around Africa. She ate, drank, and socialized. She climbed trees. And that, if John Kappelman from the University of Texas at Austin is right, is how she died.
Who knows exactly what happened? Maybe she mistimed a jump. Maybe a dry branch gave way beneath her. Maybe she was distracted by a bird. Maybe she was pushed. Whatever the case, Kappelman thinks that Lucy fell—from the tree, to her death, and into history.
He met Lucy in 2008, when she went on tour in the US. Kappelman persuaded the Ethiopian government to send her bones on a brief detour to Austin, so he could put them in a medical CT scanner. Such devices were around when Lucy was first discovered, but they were still crude. Kappelman, however, had access to a high-resolution, state-of-the-art machine. “We had Lucy here for 10 days and we scanned every last bit of bone in her entire skeleton,” he says. “We’ve been working on those scans ever since.”