British paleoanthropologist
English archaeologist and paleontologist whose crucial discoveries include Proconsul africanus, a 1.7 million-year-old dryopithecine (primitive ape) in 1948, at Rusinga Island, in Lake Victoria; then the 1.75 million-year-old hominid Zinjanthropus (later reclassified as Australopithecus boisei) at Olduvai Gorge in Tanzania, in 1959; and Homo habilis, a new species contemporary with, but more advanced than, Zinjanthropus in 1960-1963. Also remarkable was her excavation in 1976 at Laetoli, Tanzania, of fossilized hominid footprints, preserved in volcanic ash, which proved that our ancestors already walked upright 3.6 million years ago.