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Origins of Humankind
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The Hominid Family Tree

Orrorin tugenensis
(6 mya)

Ardipithecus ramidus
(4.4 mya)

Australopithecus anamensis
(4.2 to 3.9 mya)

Australopithecus afarensis
(3.6 to 2.9 mya)

Kenyanthropus platyops
(3.5 to 3.3 mya)

Australopithecus africanus
(3 to 2 mya)

Australopithecus aethiopicus
(2.7 to 2.3 mya)

Australopithecus garhi
(2.5 mya)

Australopithecus boisei
(2.3 to 1.4 mya)

Homo habilis
(2.3 to 1.6 mya)

Homo erectus
(1.8 to 0.3 mya)

Australopithecus robustus
(1.8 to 1.5 mya)

Homo heidelbergensis
(600 to 100 tya)

Homo neanderthalensis
(250 to 30 tya)

Homo sapiens
(100 tya to present)

mya = millions of years ago        tya = thousands of years ago

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Homo habilis (2.3 to 1.6 million years ago)

Species Description:

Homo habilis has been a controversial species since it was first described in the mid-1960s. Originally, many scientists did not accept its validity, believing that all specimens should be assigned either to the genus Australopithecus or to Homo erectus. Today, H. habilis is widely accepted as a species.

Some scientists, however, still believe that many of the earliest fossils assigned to H. habilis are too fragmented and separated in time for conclusions about their relationships or species compositions to be possible. H. habilis specimens with particularly large features -- brains or teeth, for instance -- are sometimes assigned as Homo rudolfensis.

Homo habilis, "handy man," is so called because of the wealth of tools that have been found with its fossils. The average H. habilis brain was considerably larger than the average Australopithecus brain. The brain shape is also more humanlike. The bulge of Broca's area, essential for speech, is visible in one H. habilis brain cast, indicating that the species may have been capable of rudimentary speech. The average H. habilis individual is thought to have been about five feet tall and 100 pounds, although females may have been smaller.

Fossil Finds:

The Mystery Skull (debated)
Estimated age: 1.85 million years
Date of discovery: 1973
Location: Koobi Fora, Kenya

The mystery of this specimen's identity may never be solved. This cranium is so different from any other specimen that there is still no consensus about what it really is. The sagittal crest resembles a common A. boisei trait, but the teeth are too small to be from that species.

Dik-dik Hominid

Dik-dik Hominid
Estimated age: 1.8 million years
Date of discovery: 1986
Location: Olduvai Gorge, Tanzania

This is a typical hominid fossil specimen, made up of very small fragments. The height of this H. habilis individual, estimated at 3 feet 5 inches tall based on arm and leg bone lengths, is very small for the species. It was most likely a female.

Olduvai George
Estimated age: 1.7 million years
Date of discovery: 1963
Location: Olduvai Gorge, Tanzania

Cattle trampled this specimen before it was found, so much of the skull was lost. It consists of teeth and skull fragments.

KNM-ER 1470
Estimated age: 1.9 million years
Location: Koobi Fora, Kenya

This is the most complete H. habilis skull known. The brain case is much larger than any australopithecine skull and lacks the large brow ridges typical of Homo erectus. Some people call this specimen H. rudolfensis.

Evidence of Culture:

Oldowan stone tools
Estimated age: 1.8 million years
Location: Olduvai Gorge, Tanzania

These tools, like most others from the same period, were made by chipping pieces from chunks of volcanic rock to reveal sharp, jagged edges.

-> Go to Homo erectus

 
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