Ancient Foot Fossil Reveals New Insights on Hominid Evolution
A peculiar foot fossil discovered in Ethiopia over a decade ago might finally be shedding some light on our evolutionary history, scientists suggest.
A recent study claims that the 3.4-million-year-old “Bartele’s Foot,” found in 2009, is linked to Australopithecus deiremeda, a contentious ancestor of humans that coexisted with the famous “Lucy.” This was published in Tuesday’s issue of Nature magazine.
The researchers behind the initial discovery named the new species back in 2015 after uncovering another 3.4-million-year-old jawbone at the same site. However, it wasn’t until this new research that they could confirm the link between Bartele’s feet and early humans.
Interestingly, Australopithecus deiremeda exhibited traits similar to modern species, like smaller canine teeth akin to those of Australopithecus afarensis (Lucy’s species), as well as more primitive features, including opposable thumbs ideal for climbing.
Despite having feet suited for climbing, this hominid walked upright, highlighting the differences in locomotion among hominids living during the same period.
Johannes Haile Selassie, the lead author and paleoanthropologist at Arizona State University, remarked, “What we’re learning now is that while bipedalism was certainly important in our evolutionary journey, there were various ways to be bipedal on land.” It’s a shift in perspective, given the prior belief that humans had fully developed bipedalism when Lucy was around.
Lucy, discovered in Ethiopia in 1975 and measuring about 3.5 feet tall, provides strong evidence that our distant ancestors were walking on two legs as early as 3 million years ago.
The distinct grasping of the big toe suggested that Au. deiremeda might have spent more time in trees compared to Lucy, who appeared to have predominantly remained on the ground.
Haile Selassie mentioned that the identity of the species corresponding to Bartele’s foot remained uncertain for a long time due to the need for a skull for proper classification.
Returning to the Wolanso Mir site in the Afar region, the research team unearthed 13 new teeth and fragments of jaw fossils from the same era near Bartele’s foot. Ultimately, they were able to determine “with confidence” that the limbs belonged to Au. deiremeda.
Opinions among scientists regarding the designation of Bartele’s foot as a hominid vary, but many are excited about the potential for further research into how Lucy and other similar species cohabitated.
Haile Selassie expressed, “I think this is the best way to understand how variations in diet and exercise can exist together.” And he added, “Is that surprising? Probably not, considering that modern primates, who are closely related, share the same habitats today.”
