Hill crawls and surface sweeps are very laborious survey techniques designed to recover every tiny piece of fossil on the ground. At the Pliocene locality at South Turkwel, the crew was tasked with finding additional Australopithecus remains. The first species in that genus, Australopithecus anamensis, is possibly ancestral to modern humans and bipedal in ability but uncommitted to that form of locomotion. Fossil morphology suggests that A. anamensis was partly arboreal. Indeed, tree climbing remained a key behavioral trait in early hominins until the appearance of the first Homo species around 2.5 million year ago. The species shares many traits with Australopithecus afarensis (the specimen nicknamed "Lucy" being its most famous representative) and may well be its direct ancestor. Recent stratigraphic sequencing dates A. anamensis to between 4.1 and 4.2 million years ago.
South Turkwel 2013