New jaw fossils might suggest a direct line of descent between two species of early humans, including the one to which "Lucy" belongs. The 3.2 million-year-old Lucy, the earliest known hominid, was found in Ethiopia in 1974 by U.S. paleontologists Donald Johanson and Tom Gray. Lucy and her kind, Australopithecus afarensis, stood upright and walked on two feet, though they might also have been agile tree-climbers. Anthropologists have suspected an ancestor-descendant relationship between the Lucy species and a predecessor — Australopithecus anamensis — based on