In 1998, a unique fossil was discovered in South Africa’s Sterkfontein Caves, a site long associated with discoveries of interest to paleoanthropologists. The specimen, nicknamed “Little Foot,” was believed to have belonged to the genus Australopithecus, an enigmatic group of ancient human ancestors who once thrived in South Africa as much as 3 million years ago, and were among the earliest known to adopt bipedalism.
However, Little Foot’s identification as a member of Australopithecus is now being reconsidered, according to findings by an international study team led by scientists with La Trobe University in Australia, in cooperation with the University of Cambridge.
The findings, published in the American Journal of Biological Anthropology, now dispute that earlier classification, and instead point to an intriguing possibility: that Little Foot may be an entirely unrecognized early human species.
Little Foot Reconsidered
Little Foot’s story is a fascinating one and involves a laborious excavation and analysis process spanning nearly two decades. Led by paleoanthropologist Ronald Clarke, the groundbreaking research into this curious ancient human fossil revealed it in 2017 to belong to the species known as Australopithecus prometheus, representing the most complete example of an ancient hominin known from the fossil record.
This species, known since its first description in the mid 1920s by Australian anatomist Raymond Dart, seemed like a very good match at the time, especially since this member of the Australopithecine family was already widely known to have thrived in the area millions of years ago, based on past discoveries made at the same site.
However, something about Little Foot seemed to be slightly out-of-step in terms of its association with Australopithecus prometheus, according to Dr. Jesse Martin, a La Trobe University adjunct professor. Martin’s analysis, which forms the basis of the new peer-reviewed research, revealed that while similar to other members of the Australopithecus genus, Little Foot also seems to lack several of the specific traits associated with these species.
This raises a striking prospect: that Little Foot might not belong to these known groups at all.
A Major Paleoanthropological Discovery
“This fossil remains one of the most important discoveries in the hominin record and its true identity is key to understanding our evolutionary past,” Dr. Martin said in a recent statement, adding that he and his colleagues “think it’s demonstrably not the case that it’s A.prometheusor A. africanus.”
While the story behind this unique fossil is turning out to be more complex than once thought, Martin emphasized that Clarke’s earlier work was important for having been not only responsible for Little Foot’s discovery, but also being the first to suggest the presence of two separate hominin species in the fossils at Sterkfontein.
“Little Foot demonstrates in all likelihood he’s right about that,” Martin said. “There are two species.”
However, he adds that his team’s recent analysis challenges the “current classification of Little Foot and highlight the need for further careful, evidence-based taxonomy in human evolution.”
Next Steps for Little Foot
Currently, Martin and his team are working to try and uncover additional clues that will help them more precisely determine which class of ancient hominin Little Foot belongs to.
“It is clearly different from the type specimen of Australopithecus prometheus, which was a name defined on the idea these early humans made fire,” said Andy Herries, a professor at La Trobe University also associated with the recent research, adding regarding the species’ purported fire use that “we now know they didn’t.
“Its importance and difference to other contemporary fossils clearly show the need for defining it as its own unique species,” Herries added.
For Martin and his team, ongoing work will likely reveal additional details about this mystery of ancient human ancestry, although based on his team’s current findings, Little Foot’s associations with known hominin types in the region seem to be clearly off the table.
“This is more likely a previously unidentified, human relative,” Martin concludes.
The team’s findings were detailed in the recent paper, “The StW 573 Little Foot Fossil Should Not Be Attributed to Australopithecus Prometheus,” which appeared in American Journal of Biological Anthropologyon November 29, 2025.
Micah Hanks is the Editor-in-Chief and Co-Founder of The Debrief. A longtime reporter on science, defense, and technology with a focus on space and astronomy, he can be reached at micah@thedebrief.org. Follow him on X @MicahHanks, and at micahhanks.com.