Lucy, easily the most famous ancient human ancestor ever discovered, has taught us a great deal about human evolution, but has also left us with some pretty good mysteries as well. One of them, how she died, seems to have been solved recently thanks to forensic science and modern technology. Lucy, a 40% complete specimen of Australopithecus afarensis, is about 3.18 million years old, making her the oldest, most complete specimen of an adult walking ancestor. She’s pretty famous.
In 2008, while on tour in the United States, she was scanned with computed tomography technology that gave us 35,000 scans without damaging the bones themselves. Since then, researchers at the University of Texas have used those scans to figure out how she died.
Though Lucy was comfortable on both land and in trees, she ironically died from falling out of a tree. Not only do we know that’s how she died, we also know she fell from about 40 feet. Calculations show that she fell at 35 miles per hour, and that she landed on her legs and fell forward as she attempted to break her fall with her hands. She died shortly afterwards.
Researchers gathered this information from Lucy’s bone fractures and splinters, which showed no signs of having healed, and could have only resulted from such a fall. The only way she could have fallen from such great heights was from a tree.
Though the knowledge of how she died helps to further humanize Lucy, it might also help us learn more about the transition our ancestors made from living in trees to living on the ground. Lucy and her peers probably foraged on the ground, and then climbed trees for safety at night. Because of fatalities like Lucy’s, Australopithecus likely switched from sleeping in trees to sleeping on the ground because trees were starting to pose more of a hazard than a benefit.