Scrutable

Some 3.6 million years ago, an upright walking creature trudged through layers of freshly fallen volcanic ash in what today is northern Tanzania. When anthropologists uncovered five of its fossilized footprints nearly 50 years ago, they couldn’t say whether this ancient biped was a hominin, a bear, or some other ape. Now, a new team claims to have solved this paleontological cold case, identifying the mystery walker as an unknown species of hominin. If true, this creature lived in the same place at the same time as the famed human ancestor, “Lucy.” It would also offer a window into the early day of our distant ancestors’ evolutionary forays into bipedalism.