Donald Johanson and Tom Gray had just concluded a long, hot November morning of mapping and surveying for fossils near the village of Hadar, Ethiopia. En route back to their Land Rover, the paleontologists detoured through a gully where something caught Johanson’s...

Donald Johanson and Tom Gray had just concluded a long, hot November morning of mapping and surveying for fossils near the village of Hadar, Ethiopia. En route back to their Land Rover, the paleontologists detoured through a gully where something caught Johanson’s...