Which hominin species is represented by the partial skeleton nicknamed “Ardi,” found in Ethiopia?

The partial skeleton nicknamed “Ardi,” found in Ethiopia, represents the hominin species Ardipithecus ramidus.

Ardi was discovered in the Afar Depression and described in detail in 2009. The skeleton is about 4.4 million years old, making it substantially older than the famous Australopithecus afarensis skeleton Lucy, which is about 3.2 million years old.

Ardipithecus ramidus had a mixture of traits. Its reduced canine teeth and some aspects of its pelvis suggest hominin relationships, while its grasping big toe and other foot features indicate substantial climbing ability. Researchers therefore use it to study an early stage of human evolution, not as a simple “missing link.”

The species name combines Ardipithecus, meaning roughly “ground ape,” with ramidus, a word from the Afar language associated with roots. Its anatomy has also influenced debates about how and when habitual bipedalism evolved.