This article first appeared in telegraph.co.uk and is written by Sarah Knapton
Stone tools have been found that are older than man, suggesting that our ancient ancestors were already skilled toolmakers before evolving into humans.
In a discovery which could, rewrite the history books, archaeologists working in northwestern Kenya found sharp cutting tools which date back to 700,000 years before the first ‘homo’ emerged.
The finding, which was described as ‘momentous’ is so significant because the making of stone tools is generally thought to mark the birth of humanity as it demonstrates significant mental ability and hand coordination.
But the tools show that earlier hominids – our ancestors who lie between humans and apes – were already well advanced.
Writing in the journal Nature, the researchers said the tools represent “a new beginning to the known archaeological record.”
The team from Lamont-Doherty Earth Observatory and Rutgers University, US, found 149 stone artifacts tied to tool-making, including stone cores, flakes, rocks used for hammering and anvils to strike on.
“The whole site’s surprising, it just rewrites the book on a lot of things that we thought were true,” said Professor Chris Lepre a co-author of the paper who precisely dated the artifacts.
Archaeologists long thought that our relatives in the genus Homo – the line leading directly to Homo sapiens – were the first to craft stone tools.
But recently researchers have been uncovering tantalizing clues that some other, earlier species of hominid might have figured it out.
The skull of a 3.3-million-year-old Kenyanthropus platytops, was found in 1999 about a kilometer from a toolmaking site, but there was no evidence directly linking the two finds.
However the new tools were found above a layer of volcanic ash which precisely dates them to 3.3 million years ago.
“This is a momentous and well-researched discovery,” said paleoanthropologist Bernard Wood of George Washington University,
The team also looked at the soil, and nearby animal fossils to determine what the environment would have looked like at the time And they were intrigued to find that it was a partially woodd, shrubby environment.
That challenges current thinking that sophisticated tool-making came in response to a change in climate that led to the spread of broad savannah grasslands, and the evolution of large groups of animals that could serve as a source of food for human ancestors
It was believed hominins started knapping – banging one rock against another to make sharp-edged stones – so they could cut meat off of animal carcasses, said paper co-author Dr Jason Lewis of the Turkana Basin Institute and Rutgers.
“But the size and markings of the newly discovered tools suggests they were doing something different as well, especially if they were in a more wooded environment with access to various plant resources,” said Dr Lewis.
The researchers think the tools could have been used for breaking open nuts or tubers, bashing open dead logs to get at insects inside, in the same way that chimps do today.
“The tools shed light on an unexpected and previously unknown period of hominin behavior and can tell us a lot about cognitive development in our ancestors that we can’t understand from fossils alone,” said lead author Sonia Harmand, of the Turkana Basin Institute at Stony Brook University.
Ancient stone artifacts from East Africa were first uncovered at Olduvai Gorge in Tanzania in the mid-20th century, and those tools were later associated with fossil discoveries in the 1960s of the early human ancestor Homo habilis. That species has been dated to 2.1 million to 1.5 million years ago.
Subsequent finds have pushed back the dates of humans’ evolutionary ancestors, and of stone tools, raising questions about who first made that cognitive leap. The discovery of a partial lower jaw in the Afar region of Ethiopia, announced on March 4, pushes the fossil record for the genus Homo to 2.8 million years ago.
Sarah Knapton is the Science Editor of Telegraph.
