WIKIMEDIA, NACHOSANAround 3.18 million years ago, a young adult hominid died. But the cause of her death has remained a mystery. Now, an international team led by researchers at the University of Texas (UT) at Austin has proposed that this famous member of the bipedal Australopithecus afarensis—best known as “Lucy”—died of traumatic injuries after falling from a tree. The team published its hypothesis Monday (August 29) in Nature.
The team first scanned Lucy’s bones, which represent about 40 percent of her complete skeleton, using X-ray computed tomography. The technique allowed them to peer deep into the fossils, and trace the webs of fractures within.
A key piece of evidence to unravelling the mystery of Lucy’s death lay in a fracture between her shoulder and elbow—an unusual injury in fossils, but one seen after accidents in humans.
From this and other fractures across her body, the team surmised that Lucy fell from a height, potentially 40 feet up, and hit the ground at a speed of 35 miles per hour. She landed feet first, the team proposed, and—toppling forward—braced herself with outstretched arms.
“When the extent of Lucy’s multiple injuries first came into focus, ...
