Ardipithecus kadabba

Ardipithecus kadabba remains have been found in East Africa at Middle Awash and at Gona, Ethiopia.

Ar. kadabba retains many primitive characters, including relatively thin enamel, a possible honing complex, and a humerus and manual phalanges typically of arboreality. However, Ar. kadabba also has a reduced canine. A left foot phalanx, some 600,000 years (Ka) younger than many of the other specimens, and found some 20 km to the east, shows a morphology intermediate between apes and A. afarensis, which may indicates incipient bipedalism. (However, because the phalanx is isolated in time and space, it's assignment to A. kadabba is tentative).

Some scientists argue that Ardipithecus may represent the last common ancestor to chimpanzees and humans, while others believe there is not enough data to support this claim.

ALA-VP 1/20 is the type specimen for Ar. kadabba, which was found at Middle Awash and dates between 5.8 and 5.5 million years ago.