Oldest-known stone tools pre-date Homo

May 20, 2015
Tool unearthed at excavation site. Credit: MPK-WTAP

Scientists working in the desert badlands of northwestern Kenya have found stone tools dating back 3.3 million years, long before the advent of modern humans, and by far the oldest such artifacts yet discovered. The tools, whose makers may or may not have been some sort of human ancestor, push the known date of such tools back by 700,000 years; they also may challenge the notion that our own most direct ancestors were the first to bang two rocks together to create a new technology.

The discovery is the first evidence that an even earlier group of proto-humans may have had the thinking abilities needed to figure out how to make sharp-edged tools. The stone tools mark "a new beginning to the known archaeological record," say the authors of a new paper about the discovery, published today in the leading scientific journal Nature.

"The whole site's surprising, it just rewrites the book on a lot of things that we thought were true," said geologist Chris Lepre of the Lamont-Doherty Earth Observatory and Rutgers University, a co-author of the paper who precisely dated the artifacts.

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 and the Universite? Paris Ouest Nanterre.

Hominins are a group of species that includes , Homo sapiens, and our closest evolutionary ancestors. Anthropologists long thought that our relatives in the genus Homo - the line leading directly to Homo sapiens - were the first to craft such stone tools. But researchers have been uncovering tantalizing clues that some other, earlier species of hominin, distant cousins, if you will, might have figured it out.

The researchers do not know who made these oldest of tools. But earlier finds suggest a possible answer: The skull of a 3.3-million-year-old hominin, Kenyanthropus platytops, was found in 1999 about a kilometer from the tool site. A K. platyops tooth and a bone from a skull were discovered a few hundred meters away, and an as-yet unidentified tooth has been found about 100 meters away.

The precise of modern humans is contentious, and so far, no one knows exactly how K. platyops relates to other hominin species. Kenyanthropus predates the earliest known Homo species by a half a million years. This species could have made the tools; or, the toolmaker could have been some other species from the same era, such as Australopithecus afarensis, or an as-yet undiscovered early type of Homo.

Sammy Lokorodi, a resident of Kenya's northwestern desert who works as a fossil and artifact hunter, led the way to a trove of 3.3 million-year-old tools. Credit: West Turkana Archaeological Project

Lepre said a layer of volcanic ash below the tool site set a "floor" on the site's age: It matched ash elsewhere that had been dated to about 3.3 million years ago, based on the ratio of argon isotopes in the material. To more sharply define the time period of the tools, Lepre and co-author and Lamont-Doherty colleague Dennis Kent examined magnetic minerals beneath, around and above the spots where the tools were found.

The Earth's magnetic field periodically reverses itself, and the chronology of those changes is well documented going back millions of years. "We essentially have a magnetic tape recorder that records the magnetic field ... the music of the outer core," Kent said. By tracing the variations in the polarity of the samples, they dated the site to 3.33 million to 3.11 million years.

Lepre's wife and another co-author, Rhoda Quinn of Rutgers, studied carbon isotopes in the soil, which along with animal fossils at the site allowed researchers to reconstruct the area's vegetation. This led to another surprise: The area was at that time a partially wooded, shrubby environment. Conventional thinking has been that sophisticated tool-making came in response to a change in climate that led to the spread of broad savannah grasslands, and the consequent evolution of large groups of animals that could serve as a source of food for human ancestors.

Chris Lepre of Columbia University's Lamont-Doherty Earth Observatory (back to camera) precisely dated the artifacts by analyzing layers above, around and below them for reversals in earth's magnetic field. Credit: West Turkana Archaeological Project

One line of thinking is that 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 Jason Lewis of the Turkana Basin Institute and Rutgers. But the size and markings of the newly discovered tools "suggest they were doing something different as well, especially if they were in a more wooded environment with access to various plant resources," Lewis said. The researchers think the tools could have been used for breaking open nuts or tubers, bashing open dead logs to get at insects inside, or maybe something not yet thought of.

"The capabilities of our ancestors and the environmental forces leading to early stone technology are a great scientific mystery," said Richard Potts, director of the Human Origins Program at the Smithsonian's National Museum of Natural History, who was not involved in the research. The newly dated tools "begin to lift the veil on that mystery, at an earlier time than expected," he said.

Potts said he had examined the stone tools during a visit to Kenya in February.

"Researchers have thought there must be some way of flaking stone that preceded the simplest tools known until now," he said. "Harmand's team shows us just what this even simpler altering of rocks looked like before technology became a fundamental part of early human behavior."

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 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. Evidence from recent papers, the authors note, suggests that there is anatomical evidence that Homo had evolved into several distinct lines by 2 million years ago.

There is some evidence of more primitive tool use going back even before the new find. In 2009, researchers at Dikika, Ethiopia, dug up 3.39 million-year-old animal bones marked with slashes and other cut marks, evidence that someone used stones to trim flesh from and perhaps crush bones to get at the marrow inside. That is the earliest evidence of meat and marrow consumption by hominins. No tools were found at the site, so it's unclear whether the marks were made with crafted tools or simply sharp-edged stones. The only hominin fossil remains in the area dating to that time are from Australopithecus afarensis.

The new find came about almost by accident: Harmand and Lewis said that on the morning of July 9, 2011, they had wandered off on the wrong path, and climbed a hill to scout a fresh route back to their intended track. They wrote that they "could feel that something was special about this particular place." They fanned out and surveyed a nearby patch of craggy outcrops. "By teatime," they wrote, "local Turkana tribesman Sammy Lokorodi had helped [us] spot what [we] had come searching for."

The finds were made in the desert badlands near Lake Turkana, Kenya. Many other important discoveries of fossils and artifacts have been made nearby. Credit: West Turkana Archaeological Project

By the end of the 2012 field season, excavations at the site, named Lomekwi 3, had uncovered 149 tied to tool-making, from stone cores and flakes to rocks used for hammering and others possibly used as anvils to strike on.

The researchers tried knapping stones themselves to better understand how the tools they found might have been made. They concluded that the techniques used "could represent a technological stage between a hypothetical pounding-oriented stone tool use by an earlier hominin and the flaking-oriented knapping behavior of [later] toolmakers." Chimpanzees and other primates are known to use a stone to hammer open nuts atop another stone. But using a stone for multiple purposes, and using one to crack apart another into a sharper tool, is more advanced behavior.

The find also has implications for understanding the evolution of the human brain. The toolmaking required a level of hand motor control that suggests that changes in the brain and spinal tract needed for such activity could have occurred before 3.3 million years ago, the authors said.

"This is a momentous and well-researched discovery," said paleoanthropologist Bernard Wood of George Washington University, who was not involved in the study. "I have seen some of these artifacts in the flesh, and I am convinced they were fashioned deliberately." Wood said he found it intriguing to see how different the tools are from so-called Oldowan , which up to now have been considered the oldest and most primitive.

Lepre, who has been conducting fieldwork in eastern Africa for about 15 years, said he arrived at the dig site about a week after the discovery. The site is several hours' drive on rough roads from the nearest town, located in a hot, dry landscape he said is reminiscent of Arizona and New Mexico. Lepre collected chunks of sediment from a series of depths and brought them back to Lamont-Doherty for analysis. He and Kent used a bandsaw to trim the samples into sugar cube-size blocks and inserted them into a magnetometer, which measured the polarity of tiny grains of the minerals hematite and magnetite contained in the sediment.

"The magnetics pretty much clinches that the age is something like 3.3 million years old," said Kent, who also is a professor at Rutgers.

Earlier dating work by Lepre and Kent helped lead to another landmark paper in 2011: a study that suggested Homo erectus, another precursor to modern humans, was using more advanced tool-making methods 1.8 million years ago, at least 300,000 years earlier than previously thought.

"I realized when you [figure out] these things, you don't solve anything, you just open up new questions," said Lepre. "I get excited, then realize there's a lot more work to do."

Explore further: Humans shaped stone axes 1.8 million years ago, study says

More information: 3.3-million-year-old stone tools from Lomekwi 3, West Turkana, Kenya, Nature, nature.com/articles/doi:10.1038/nature14464

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baudrunner
1.4 / 5 (9) May 20, 2015
The club would be the first tool used by early man for killing game and for knapping candidate stones to scrape the hides of the animals they killed. The effectiveness of the sharp edge was not lost on these proto-humans, and their use evolved into axes and spears, then arrows.
Stevepidge
1.3 / 5 (12) May 20, 2015
it's.. a ROCK!!! Stop the presses!!
AGreatWhopper
1.3 / 5 (6) May 20, 2015
It could have been antlers as well. You've been watching too many stupid movies. I f'ing detest idiots that sit around and pontificate. Usually some fat sorry loser.
AGreatWhopper
2.8 / 5 (9) May 20, 2015
Can't even post that before ANOTHER idiot has to drool his wisdumb!

Obviously the Kochs, et al. are paying the trolls for more than just climate trolling.
Dug
3.4 / 5 (7) May 20, 2015
Besides our modern primate cousins extensive tool use - tool use is not restricted to just primates. Sea otters have been cracking clams with rocks for quite a while also - one stone on their chest (the anvil stone) and the other in their "hands" (the hammer stone.). Some birds use gravity as a tool and drop snails and other prey from height to "open" them up for easier access. Many species across the animal kingdom, build shelter (and traps) with a broad array of materials (sticks, pebbles, stones, mud, mastications/secretions, etc.) - using their appendages as "tools" to manipulate these materials into the desired, predictable, and specifically functional shapes - and whether such "tool" use is instinct based, or acquired learning based - both are forms of higher intelligence. Perhaps tool making isn't such a restricted or meaningful indicator of higher intelligence as some of us "special" humans think.
Eddy Courant
2.7 / 5 (3) May 20, 2015
That's early Rockwell. Cutting edge technology.
Rustybolts
5 / 5 (4) May 21, 2015
"AGreatWhopper - Usually some fat sorry loser." irony at its finest!
ThomasQuinn
4.5 / 5 (8) May 21, 2015
Isotopic dating methods are useless because we do not know from what date started and how they аре influenced by the physical factors of the environment in real time of their existence. They are useful only for the industry in the mythology in the society to maintain the myth of evolution.


Not only are you trying to promote anti-scientific drivel, apparently, you are also unable to write a legible English sentence. Religious nut -> dismissed.
Job001
3.3 / 5 (4) May 21, 2015
A theory to test;Apes crudely accidentally shaped these stones by long term use cracking nuts on top of a "back up" rock. When the upper stone glances off the nut it will tilt somewhat into a napping position.
Torbjorn_Larsson_OM
5 / 5 (6) May 21, 2015
Well, that clinches it. I usually await anthropologist John Hawks's take on these things, but the dating method and the number of tools precluding accidental or deliberate burying looks pretty definitive.

And if the technique shows that there long has been selection for doing tools - "required a level of hand motor control that suggests that changes in the brain and spinal tract needed for such activity could have occurred" - that means both older tool use and it being an important way to provide food sources.

Now let us sit back and see how people square this find a conventional way of defining Homo as "tool user". Maybe Australopithecus or Kenyanthropus should clade within an extended Homo clade. (More likely, since there is no conclusive fossil association, it won't go _that_ far.)
Torbjorn_Larsson_OM
5 / 5 (3) May 21, 2015
Dug, it starts with fishes (some use stones for hammering open stuff, like birds) among bilaterians, but some cnidarians (octopuses) can use tools too.

Job, good idea! But they found punches with points. More generally, flaking means the stones have to be oriented. I am no specialist, but I saw the tool set elsewhere and the flake cores were definitely oriented as there are no false hits in between flakings.

@baudrunner, AGW: Prove it!

@Stevepidge, Ren: It's ... a TROLL!!! Stop the presses!!
KBK
1.7 / 5 (6) May 21, 2015
See 'forbidden archeology' by Michael A. Cremo and Richard L. Thompson. 'Forbidden archeology', is about the things that are totally counter to the understanding of life on this planet. Things that would turn your understanding of humans, life, evolution and the nature of reality itself, completely upside down.

The book is about things that PTB and oligarch types desire to remain completely hidden and unknown. Things that break all your concepts of who and what you are. These are real finds, real research, real archeology that has been denied existence, forced out of the system.

World class highly reputed archeologists have been ruined and exorcized by the forced representation of a controlled history.

We're talking about suppression of evidence, on a massive level.

Science is about investigation and truths, no matter the level of personal discomfort-- so take a look, and prepare for discomfort.
Uncle Ira
3.9 / 5 (7) May 21, 2015
I wish they would put up some better pictures because it just looks like a rock to me. But it is pretty interesting this sort of stuffs.
Stevepidge
1 / 5 (4) May 21, 2015
I wish they would put up some better pictures because it just looks like a rock to me. But it is pretty interesting this sort of stuffs.


If it quacks like a duck.. Looks to me like they were fishing for funding. There is a reason the pictures are terrible. Because it is just a darn rock.
ThomasQuinn
5 / 5 (4) May 22, 2015
I wish they would put up some better pictures because it just looks like a rock to me. But it is pretty interesting this sort of stuffs.


If it quacks like a duck.. Looks to me like they were fishing for funding. There is a reason the pictures are terrible. Because it is just a darn rock.


You clearly haven't even read the article, much less looked into the subject with any depth. More than 200 tools were recovered, and you are trying to discredit that by making ignorant remarks about one picture. People like you, who don't have a clue what they are talking about, should just shut up. If you refuse to educate yourself and instead choose to just spew your gall on scientific investigation, just take up a menial job and spend your free time killing brain cells with alcohol.
mreda14
1.7 / 5 (3) May 22, 2015
What about the possibility that these primitive stone tools are made from Volcanic eruption or meteorite impact.
PhotonX
5 / 5 (2) May 22, 2015
What about the possibility that these primitive stone tools are made from Volcanic eruption or meteorite impact.
I possess one crude Native American hand ax made of vesicular basalt, but it's a poor material to work with and was used only because better material was lacking. I suspect that you meant to say *by* eruption or impact (not *from*), and while I'm neither a geologist or anthropologist, IMHO the chances of pseudo-tools being formed from either of those natural means are zero. I've lived in volcanic regions (e.g. Modoc plateau volcanics, Tuscon Mt. rhyolite) for most of my life, and no natural volcanic ejecta or lava flow material I've ever seen looks like this. Impact ejecta might seem a likelier possibility, but impacts create distinctive signatures such as shocked quartz that experts well know, and wouldn't explain the series of discrete strikes required to form even a single stone tool, never mind hundreds at the same site.
PhotonX
5 / 5 (2) May 22, 2015
baudrunner:
The club would be the first tool used by early man for killing game and for knapping candidate stones
I'd pay to watch someone using a piece of wood to knap a sharp edged stone. Or are you suggesting they carried solid stone clubs around?
Ren82:
Isotopic dating methods are useless because we do not know from what date started and how they аре influenced by the physical factors of the environment in real time of their existence.
Likelier, you just don't understand how such dating works. Don't the scriptures explain that?
They are useful only for the industry in the mythology in the society to maintain the myth of evolution.
And those same scriptures don't represent a mythological industry all of their own? Please, the irony is killing me.
PhotonX
5 / 5 (5) May 22, 2015
Stevepidge:
There is a reason the pictures are terrible. Because it is just a darn rock.
No, they're good pictures, they're many rocks, not just one, and since you didn't seem to notice, they're in situ, not isolated pieces. Context matters. You can see that it's a worked piece, with multiple discrete edges, and it's sitting at a carefully determined layer, not just some random river rock somebody picked up.
Arrowstone
1 / 5 (3) May 23, 2015
Oh dear, this is starting to sound like Hindu fundamentalism. The infamous Michael Cremo had the audacity in 'Forbidden Archaeology' to mention the recovery of artifacts and remains of apparently homo provenance from beneath Table Mountain in California, which, considering the well-verified age of the overlying stone, had to be at least 9 million years old. For this and much else, he has been pilloried as a psuedoscientist and worse things. Beware of reporting anything very far removed from orthodoxy. You will be made to pay... Already I see the amateur skeptics are having a field day. Hopefully we'll hear from some who can actually construct decent arguments.
Arrowstone
1 / 5 (3) May 23, 2015
Oh yes, it might also be interesting to compare this to such sites as Calico Hills, Hueyatlaco and Sheguiandah in North America. At each of these places stones were found resembling assemblages from Asia which are considered to be artifacts rather than geofacts. The finds were fairly convincingly dated much earlier than any currently accepted artifacts from the Americas. However their out-of-place discovery in the Americas prima facie precluded acceptance as artifacts. In this article, the location is acceptable but the indicated time-frame is anomalous. Assuming a crucial flaw is not found, it will be interesting to see how far orthodoxy is willing to stretch.
Captain Stumpy
3 / 5 (2) May 24, 2015
Isotopic dating methods are useless
@ren
wrong
the methods are based upon sound science and physics, and a far cry better then your religion's interpretations of evidence using prayer and waiting for divine inspiration (which gave us flat earth, young earth, global flood, Earth centric astronomy and inbreeding as well as genocide and theft of other religious stories for the sake of control of populace)
to maintain the myth of evolution
and again, evolution is based upon sound scientific principles which have been repeatedly linked to you

you have yet to provide an alternative that conforms to the scientific principles (especially WRT evidence) that supports your own perspectives and adherence to your personal religious dogma

there in only one reason that you continue to flood the site with your dogma: TROLLING

do you get extra life points from your sky-faerie when you die for trolling science?
Captain Stumpy
3 / 5 (2) May 24, 2015
I wish they would put up some better pictures because it just looks like a rock to me.
Uncle Ira
i agree that i would like to see more and better pictures...
it may look just like a rock to you, but think about it another way: Forensic tool markings

when something strikes or touches another object, there is invariably transfer. Often microscopic

so the rocks found have been looked at very closely (and likely with magnification, which can help a lot) and tool markings (or forced manipulation of the medium) was found

the markings will differ depending on the medium used and manipulated, just like steel will leave a distinctive pattern on stone or bone, so will other materials leave distinctive patterns which can be replicated as well as demonstrated (a major tool of scientific evidence and esp. forensics is replication)

sometimes it just looks like a rock to US, but a trained professional will tell otherwise
JVK
1 / 5 (2) May 27, 2015
Has anyone ever asked Svante Paabo why his claims about natural selection do not fit with the claims made about the fossil record and evolution? http://linkinghub...07620138
antigoracle
1 / 5 (1) May 27, 2015
It could have been antlers as well. You've been watching too many stupid movies. I f'ing detest idiots that sit around and pontificate. Usually some fat sorry loser.

Wow!
What a TOOL.
Vietvet
not rated yet May 27, 2015
Has anyone ever asked Svante Paabo why his claims about natural selection do not fit with the claims made about the fossil record and evolution? http://linkinghub...07620138


@JVK

Because there is no conflict.

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