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The first hominid to be associated with manufactured tools lived in Africa about 2.4 to 1.5 million years ago.
This is the earliest known Homo species to show distinct differences from both apes and australopithecines. The face is still primitive and projecting, but the jaw is pulled under the brain, with smaller molars (though still much larger than in modern humans), and the skull is thinner than that of the chimpanzee, with a distinctive rounded shape, vertical sides and a small forehead above the brows. The average Homo habilis brain was considerably larger than the average Australopithecus brain (about 610 cubic centimeters on average), and the bulge of Broca's area, essential for speech indicates that it may have been capable of rudimentary speech. Homo habilis was capable of walking upright, but may have also spent a considerable amount of time in the trees. The average Homo habilis individual probably stood about five feet tall and weighed about 100 pounds.
Homo habilis is associated with the Oldowan tool industry, which is characterized by crude stone flakes, rounded hammer stones, and bones used for digging. Though odd stones or pieces of bone may have been used as weapons or scrapers much earlier, Homo habilis appears to have been the first to actually make its tools, rather than simply use what was available.
Homo habilis lived in a predominantly grassland environment. The climate was becoming cooler and drier, and this may have been the impetus for new feeding strategies that included scavenging and tool use. Chemical analysis suggests that this species was mainly vegetarian but did include some meat in their diet. Most of its meat was probably scavenged from carnivore meals, however.
The study of Homo habilis began in 1959, when two teeth were unearthed at Olduvai Gorge in Tanzania by a team led by Louis and Mary Leakey. Parts of a boy's skeleton were located at the site the next year and additional fossils from other individuals continued to be found. They were officially announced as new species in 1964, but their placement into the human genus Homo has been controversial ever since. Additional fossils, including the discovery of a skull in 1973 and a partial skeleton in 1986, have revealed that this species was more ape-like than previously believed.
Most of the specimens originally named Homo habilis have now been split into two groups. One group retains the name Homo habilis, although some scientists prefer the name Australopithecus habilis because these individuals have physical similarities with the australopithecines. The other group consists of fossils with larger brains and larger teeth. These individuals are now placed in a different species, but there is debate as to whether they should be named Homo rudolfensis, Australopithecus rudolfensis or Kenyanthropus rudolfensis.
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This page was last updated on 09/07/2018.