Laetoli Hominin Footprint Trails Excavated

Between 1976 and 1978, Mary Leakey's team excavated a 27-meter trail of approximately 70 hominin footprints preserved in volcanic ash at Laetoli, Tanzania, 45 km south of Olduvai Gorge. Dated to 3.66 million years ago, the prints were made by at least two individuals walking upright through fresh ash from the nearby Sadiman volcano. The footprints demonstrated that bipedal locomotion preceded significant brain enlargement in hominin evolution. Researchers attribute the prints to Australopithecus afarensis, the same species as the Lucy skeleton.