Description

Ardipithecus kadabba (≈ 5.8 to 5.2 million years ago) is known only from teeth, jaw fragments, and a few bits of postcranial bones (toe, hand, arm, clavicle) discovered in the Middle Awash region of Ethiopia. The dating places it toward the end of the Miocene epoch, which makes it one of the earlier hominin candidates.

The toe bone discovered has a robust and dorsally inclined surface, suggesting that A. kadabba may have pushed off with the big toe in a way consistent with bipedal locomotion (though it probably retained significant arboreal capabilities). Its canines and premolars are more primitive (i.e. sharper, with some asymmetries) than in later hominins, but they show traits that foreshadow the shift away from the “honing” canine complex of apes.

Because no skull or full skeleton is known, estimates of body size, height, etc. are speculative. Some authors suggest it may have had a body plan and size roughly comparable to a modern chimpanzee.
The habitat is reconstructed as woodland, possibly mosaic forest-savanna, close to water sources such as rivers or wetlands. The paleoenvironment suggests a mixture of forest and more open patches.