A discovery by ASU researchers this month suggests early humans used technology 800,000 years earlier than previously thought.
By analyzing fragments of animal bones, the researchers on the project found evidence that humans began making tools about 3.4 million years ago, though past research showed the earliest use of tools at 2.6 million years ago.
The discovery means Lucy, an early human ancestor discovered in 1974, would have used tools to hunt animals, said Curtis Marean, an ASU professor who worked on the study at the School of Human Evolution and Social Change.
“This was an amazing discovery that has the scientific community chattering,” said Carol Hughes, spokeswoman for ASU’s College of Liberal Arts and Sciences.
In their research at ASU’s zooarchaeology lab, professors examined fragments of animal bones and found that the marks on them were made by stone tools.
“ASU's role in identifying the marks on the animal bones, using our microscopes and expertise, brings space age technology to the Stone Age,” Hughes said.
This discovery will have a major impact on the way zooarchaelogists analyze bones in future studies, Marean said.
“In the past, … field researchers focused on skull and other well-preserved fragments that could easily be identified to species,” Marean said. “These researchers now will need to focus on the small, hard-to-identify shaft fragments, as these are the ones most likely to preserve stone-tool-inflicted marks.”
Marean and Hamdallah Béarat, a researcher in the School for Engineering of Matter, Transport and Energy, were featured in the Aug. 12 edition of Nature, a science and medicine journal, for their study and analysis of marks on animal bone fragments from Lucy.
The marks on the bones were studied to determine their source, Béarat said.
“The conclusion here is that this fragment of rock has a peculiar composition, compared to the sediment that cannot be just adhered to the surface,” Béarat said during an online press conference. “It is the orientation and the composition that make us believe that it is a residual of the rock that was being used.”
ASU has played an important role in archaeological discoveries of early human ancestors. The founding director of ASU’s Institute of Human Origins was Don Johanson, the scientist who discovered Lucy, also known as Australopithecus afarensis.
“ASU has been a leader in the study of the anatomy of Australopithecus afarensis,” Marean said. “Now, ASU adds to this portfolio by showing that Lucy's species was a tool-user and meat-eater, and in so doing, shows once again that we are a top world leader in human origins studies.”
