| Species: | Homo habilis |
| Age: | 1.75 million years |
| Date of Discovery: | November 4, 1960 |
| Location: | Olduvai Gorge, Tanzania |
| Discovered by: | Jonathan Leakey |
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The partial mandible shown to the right was found in 1960 in Olduvai Gorge, Tanzania, along with two parietal bones. Labeled OH 7 ("Olduvai Hominid # 7"), this is the type specimen for the species Homo habilis. The teeth are obviously not megadont, and this suggested to the researchers that the specimen probably was not from the other early human species known at Olduvai from this time period, Paranthropus boisei. The two parietal bones allowed scientists to estimate the cranial capacity of the individual. A figure of 363cc was obtained. Accounting for the fact that this individual was a juvenile, an adult total cranial capacity of 674cc was extrapolated, placing OH 7 well out of the range of Australopithecus, yet at the same time, much smaller than H. erectus known from China or Java.
The designation of a second early human species at Olduvai in the 2 million year old range (and more importantly, a member of the genus Homo) was central to the validation of Louis Leakey's firmly held belief that the stone tools found at Olduvai were not made by australopiths.
