Scientists studying fossils in Ethiopia’s Afar Rift Valley have found evidence of another early human species that lived around the same time as Lucy, about 3.4 million years ago.
For nearly 50 years, “Lucy” has been one of the most famous fossils in the world. The 3.2-million-year-old skeleton of Australopithecus afarensis, discovered in Ethiopia in 1974, has long been regarded as an important ancestor of modern humans. But new research suggests Lucy may not be as unique as people think.
Scientists studying fossils in Ethiopia’s Afar Rift Valley have found evidence of another early human species, Australopithecus deyiremeda, which lived around the same time as Lucy, about 3.4 million years ago. The discovery challenges the idea that Lucy’s species was the only one that dominated the landscape at the time.
The team analyzed the new jaw and tooth fossils, linking them to a partial foot discovered more than a decade ago, known as the “Bertler foot.” Together, these remains suggest that A. deyiremeda is a different species than Lucy’s, and not just a regional difference.
Although Lucy’s species is well-adapted to walking on two legs, the Bertler feet suggest that A. deyiremeda can still climb trees. Their diets were also different: Chemical analysis of the teeth revealed that de Iremeda macaques relied more on fruits and leaves, while Lucy’s conspecifics had a broader diet.
An undated illustration shows the 3.4-million-year-old “Burtele foot” bone, belonging to the ancient human relative Australopithecus deyiremeda, found in the Afar Rift Valley region of Ethiopia, with its anatomical position and foot bones embedded in the outline of a gorilla (Image credit: Yohannes Haile-Selassie/Handout from Reuters)
common ancestor of humanoid species
Researchers believe A. deyiremeda may be closely related to the older species Australopithecus anamensis. If so, this suggests that multiple humanoid species may have evolved from a common ancestor, forming a branching “thicket” of early humans, rather than the linear lineage of modern humans.
This new evidence paints a picture of East Africa 3.5 million years ago, when Africa was a busy place with several species coexisting, each finding its own way of survival. While some scientists still view Lucy as humanity’s primary ancestor, it’s becoming increasingly clear that she’s not the only player in our origin story.
The story of human evolution is being rewritten as more fossils emerge from Ethiopia’s ancient landscape, showing that humanity’s path was far more complex and crowded than previously thought.