After studying the remains of a nearly 2-million-year-old being, Duke U. researchers believe they have found the oldest link in humanity’s family tree—a discovery that could cause the entire field of paleoanthropology to shift greatly.
The fossils from both a juvenile boy and an adult female in the Australopithecus sediba species were discovered in South Africa in 2008. Recent papers published by Steven Churchill, associate professor of evolutionary anthropology, have determined that this species is the base of the human genus. The remains include a foot, hand and parts of the pelvis and skulls.
According to their latest research published Sept. 8, Churchill and his team have determined that the sedibaare 1.977 million years old—a time period that is virtually unknown to science.
The species, Churchill said, lies between the end of Australopithecus lineage and the beginning of human lineage.
“Suddenly it was real to me,” he said. “I realized, wow, pretty soon everyone’s going to have a cast of this mandible in their laboratory, it’s going to be in every textbook, it’s going to change the way people teach paleoanthropology.”
Churchill first started working on the project when his colleague, paleoantrhopologist Lee Berger, found a fossil site in South Africa 17 years ago.
“Because I had a long working relationship with him, I was the first person he called” Churchill said. “I was kind of in on it from the get-go.”
Excavations began on the site just after apartheid ended in 1994. The new species was announced in April 2010. The team has since been publishing information about the species continuously.
“We’re spoiled in the fact that we have two nearly complete individuals” senior Tawnee Sparling said, who is doing her senior thesis project on the sediba and has traveled with Churchill to see the fossils. “Often fossils are just half of a mandible, and they have to infer everything from just that.”
Not only has Sparling had the opportunity to work with the fossils, but so have many others in the Duke community.
“The Malapa Team is unprecedented in the way that they’re opening up everything to the scientific community,” senior Kelly Ostrofsky said, who is also doing her senior thesis project on the sediba and has been to the site.
The team’s findings, if they prove to be correct, would have monumental consequences for theory of evolution, Churchill said, adding that there will undoubtedly be some opposition to his theories about the sediba, and its role in the development of the modern human species.
“Probably the majority of the field doesn’t buy our argument, but that’s just the way science works” Churchill said. “Whether our interpretation is right or not—this is an incredible find.”