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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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Australopithecus anamensis (4.2 to 3.9 million years ago)

Species Description:

Australopithecus anamensis possesses a mix of advanced and primitive traits. A partial tibia (the larger of the two lower leg bones) suggests that A. anamensis probably walked upright. The teeth of A. anamensis were covered with a layer of enamel much thicker than that of Ar. ramidus, suggesting a diet of hard-to-chew foods. The thickened enamel is also a trait characteristic of all later hominids. In size and shape, however, the teeth of A. anamensis were primitive relative to later hominids. A. anamensis probably lived in open woodland habitats in what is now northern Kenya and southern Ethiopia.

Fossil Finds:

KP 29285
Estimated age: 4.1 million years
Date of discovery: 1994
Location: Kanapoi, Kenya

The shape of the end of this lower leg bone, or tibia, indicates that A. anamensis probably walked upright.

KP 29281

KP 29281
Estimated age: 4 million years
Date of discovery: 1994
Location: Kanapoi, Kenya

The teeth in this jawbone are very large relative to the body size of A. anamensis. The back teeth are also large relative to the front teeth. Both traits are characteristic of all Australopithecus species.

-> Go to Australopithecus afarensis

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