Homo Habilis

Homo habilis is an extinct hominin that lived in Africa between 2.3 and 1.6 million years ago. The type specimen, OH 7 (Olduvai Hominid #7), was discovered by Louis Leakey at Olduvai Gorge, Tanzania, in 1960. It consists of a mandible and two parietal (skull) bones that are 1.7 million years old. The species (literally, “handy man”) got its name from the association of the fossil with stone tools.

Homo habilis is distinguished from Australopithecus primarily on the basis of a larger brain, smaller molars, and aspects of the hand that support an anatomical basis for toolmaking. The brain of Homo habilis is estimated to have been between 500 and 710 cc (depending on the specimen). On average, it is larger than that of australopithecines but smaller than that of Homo erectus. The body size of Homo habilishas been estimated to be about 32 kg (70.5 lbs). Relative to its body size, Homo habilis had a large brain.

There is a great deal of variation among specimens attributed to Homo habilis. Some specimens show limb proportions that are similar to australopithecines (longer arms relative to legs), while others do not. It is clear, however, that Homo habilis was a biped. A nearly complete foot from Olduvai Gorge clearly shows characters associated with bipedal locomotion. These include the presence of both middle and longitudinal arches, the alignment of the second through fifth toes, and the enlarged big toe that is in line with, rather than opposable to, the other toes. There is some indication from the foot, however, that Homo habilis also spent some time in the trees. Muscle markings on the bone suggest that the foot [Page 1190]could be easily inverted (turned sideways), which would facilitate tree climbing.

Homo habilis was once associated with the earliest evidence for making stone tools, and paleoanthropologists considered them to be the first toolmakers. These tools consist of choppers and flakes and belong to the Oldowan tradition. The tools made by Homo habilis were most likely used for scavenging meat, not hunting prey. Interestingly, there is good evidence that Homo habilis was a major staple in the diet of large cats and other predatory animals. Therefore, rather than being “man the hunter,” Homo habilis was more likely “man the hunted.”

Recently, Oldowan tools that predate Homo habilishave been found in Ethiopia. These date to 2.5 to 2.6 million years ago. The younger tools are associated with Australopithecus remains (A. garhi).The older tools are not associated with any fossils. Based on this new evidence, it now seems possible that Australopithecus, rather than Homo, was the first hominin to make and use stone tools.

To date, indisputable Homo habilis fossils have not been found outside Africa. This suggests that the migration of early humans to Europe and Asia came later in human evolution. In fact, most human cultural evolution occurred in later Homospecies. There is no clear evidence that Homo habilis controlled fire or buried their dead. Neither is there unequivocal evidence that Homo habilis was capable of vocalizing sounds recognizable as language today.

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