Ancient weapons found in Texas are believed to be the oldest ever found in North America and could shed new light on how humans came to the continent, Science Daily reported.

According to researchers, spear points and other tools discovered under several feet of sediment 40 miles northwest of Austin were dated to be 15,500 years old and pre-date Clovis, long believed to be the first people to enter the Americas.

The Clovis people invented the “Clovis point,' a spear-shaped weapon made of stone that is found in Texas and parts of the United States and northern Mexico. The weapons were made to hunt animals, including mammoths and mastodons, from 13,000 to 12,700 years ago.

“There is no doubt these weapons were used for hunting game in the area at that time,” Michael Waters, distinguished professor of anthropology and director of the Center for the Study of the First Americans at Texas A&M, who led the research, told The Daily Mail.

“The findings expand our understanding of the earliest people to explore and settle North America,” he added.

The researchers believe that the projectile point found in Texas is a distinct style created by people of an earlier migration into the Americas and would have been used between 13,500 and 15,500 years ago.

Conventional science says that the earliest settlers reached the Americas via Siberia, crossing the now-defunct Bering land bridge on foot and trekking through Canada some 13,000 years ago.

That clashes with archaeological findings that suggest humans were already living in Chile about 15,000 years ago or more and in Florida 14,500 years ago.

Scientists now believe the first Americans could have taken a coastal route along Alaska's Pacific border to enter the continent.

This theory provides an alternative narrative and could mark a step toward solving the mystery of how humans came to the Americas. </s> Texas A&M University researchers uncovered what are believed to be the oldest weapons ever found in North America.

A handful of ancient spear points were discovered under several feet of sediment at a dig site about 40 miles northwest of Austin.

Revealed to be 15,500 years old, the chert tools pre-date Clovis, a prehistoric Paleo-Indian culture that dates back roughly 13,200 to 12,900 years ago—previously believed to be the first people to enter the Americas.

“There is no doubt these weapons were used for hunting game in the area at that time,” professor Michael Waters, director of the Center for the Study of the First Americans at Texas A&M, said in a statement. “The discovery is significant because almost all pre-Clovis sites have stone tools, but spear points have yet to be found.

“The dream has always been to find diagnostic artifacts—such as projectile points—that can be recognized as older than Clovis and that is what we have at the [Debra L.] Friedkin site,” he added.

Waters, along with colleagues from Baylor University and the University of Texas, describes the breakthrough in a paper published this week by the journal Science Advances.

Clovis culture is named for the distinctly shaped stone spear point made by people some 13,000 years ago. Known as the “Clovis point,” the fluted weapon—found in Texas and other parts of the US and northern Mexico—was designed to hunt animals, including mammoths and mastodons.

“The findings expand our understanding of the earliest people to explore and settle North America,” Waters said.

“The peopling of the Americas during the end of the last Ice Age was a complex process and this complexity is seen in their genetic record,” the professor explained. “Now we are starting to see this complexity mirrored in the archaeological record.” </s> Michael Waters, distinguished professor of anthropology and director of the Center for the Study of the First Americans at Texas A&M, and colleagues from Baylor University and the University of Texas have had their work published in the current issue of Science Advances.

The team found the numerous weapons – about 3-4 inches long – while digging at what has been termed the Debra L. Friedkin site, named for the family who owns the land about 40 miles northwest of Austin in Central Texas. The site has undergone extensive archaeological work for the past 12 years.

Spear points made of chert and other tools were discovered under several feet of sediment that dating revealed to be 15,500 years old, and pre-date Clovis, who for decades were believed to be the first people to enter the Americas.

"There is no doubt these weapons were used for hunting game in the area at that time," Waters said. "The discovery is significant because almost all pre-Clovis sites have stone tools, but spear points have yet to be found. These points were found under a layer with Clovis and Folsom projectile points. Clovis is dated to 13,000 to 12,700 years ago and Folsom after that. The dream has always been to find diagnostic artifacts – such as projectile points – that can be recognized as older than Clovis and this is what we have at the Friedkin site."

Clovis is the name given to the distinctive tools made by people starting around 13,000 years ago. The Clovis people invented the "Clovis point," a spear-shaped weapon made of stone that is found in Texas and parts of the United States and northern Mexico and the weapons were made to hunt animals, including mammoths and mastodons, from 13,000 to 12,700 years ago.

"The findings expand our understanding of the earliest people to explore and settle North America," Waters said. "The peopling of the Americas during the end of the last Ice Age was a complex process and this complexity is seen in their genetic record. Now we are starting to see this complexity mirrored in the archaeological record."

More information: Michael R. Waters et al. Pre-Clovis projectile points at the Debra L. Friedkin site, Texas—Implications for the Late Pleistocene peopling of the Americas, Science Advances (2018). DOI: 10.1126/sciadv.aat4505 </s> Scientists believe newly-discovered, 15,500-year-old spear points are the oldest weapons ever found in North America.

The findings raise new questions about the settlement of early peoples on the continent.

As reported in Science Advances, scientists found numerous weapons—about 3-4 inches long—while digging at the Debra L. Friedkin site, named for the family who owns the land about 40 miles northwest of Austin in central Texas. The site has undergone extensive archaeological work for the past 12 years.

Researchers found spear points made of chert and other tools red under several feet of sediment that dating revealed to be 15,500 years old, and pre-date Clovis, who for decades scientists believed to be the first people to enter the Americas.

“There is no doubt these weapons were used for hunting game in the area at that time,” says Michael Waters, a professor of anthropology and director of the Center for the Study of the First Americans at Texas A&M University.

“The discovery is significant because almost all pre-Clovis sites have stone tools, but spear points have yet to be found. These points were found under a layer with Clovis and Folsom projectile points. Clovis is dated to 13,000 to 12,700 years ago and Folsom after that,” Waters says.

“The dream has always been to find diagnostic artifacts—such as projectile points—that can be recognized as older than Clovis and this is what we have at the Friedkin site.”

Clovis is the name given to the distinctive tools people made starting around 13,000 years ago. The Clovis people invented the “Clovis point,” a spear-shaped weapon made of stone that researchers have found in Texas and parts of the United States and northern Mexico. Those weapons were made to hunt animals, including mammoths and mastodons, from 13,000 to 12,700 years ago.

“The findings expand our understanding of the earliest people to explore and settle North America,” Waters says. “The peopling of the Americas during the end of the last Ice Age was a complex process and this complexity is seen in their genetic record. Now we are starting to see this complexity mirrored in the archaeological record.”

Additional coauthors are from Texas A&M, Baylor University, and the University of Texas. The North Star Archaeological Research Program and the Elfrieda Frank Foundation funded the work. </s> DALLAS (AP) — Anthropology researchers have found spearheads in Central Texas that the team’s leader says are the oldest hunting tools discovered so far in North America, according to a report published this week in the journal Science Advances.

The spear points, hewn of limestone, were found in 2015 at a dig near Buttermilk Creek, which is about 45 miles north of Austin, said Michael Waters, the Texas A&M University anthropologist who led the study and director of the university’s Center for the Study of First Americans.

Waters wrote in the report that analysis suggests the spearheads are between 13,500 and 15,500 years old, which is as many as 2,500 years older than projectile points found near Clovis, New Mexico, that many believed to be the oldest in North America.

The Texas artifacts came from what is known as the Debra L. Friedkin site, which was under excavation from 2006 to 2016. The earliest people in the area were hunter-gatherers who “probably moved from camp to camp over a year,” Waters said. They were likely attracted to the site by the year-round availability of drinking water and abundant chert on the surrounding slopes that was used for making stone tools. The region also had plenty of hunting and gathering in the surrounding Hill Country, Blackland Prairie and Coastal Plain, Waters said.

As for the spear points, they were not meant as combat weapons, Waters said.

“They were used for hunting. We saw evidence that they were hafted onto a spear (shaft), and there was clear evidence they were used for butchering,” he said. “They probably would have been used for hunting everything from mammoths and horses to deer.”

Given the age and shape of the recently found spear points, the people who used them likely arrived in the area from the Pacific coast as they circumvented the ice sheet that overlaid most of North America at the time, Waters said.

James Adovasio, director of archaeology at Harbor Branch Oceanographic Institute at Florida Atlantic University, wasn’t involved in the study. He said the spear points find was “certainly the oldest in Texas,” but questioned if they were the oldest discovered in North America.

Adovasio told The Associated Press that other sites “have produced items 1,500 or 2,000 years older than Clovis.” He argued the Clovis find was no longer the standard by which subsequent finds are judged, adding that the Texas find was “in the ballpark as some of the oldest finds (in North America). It may or may not be the oldest.”

Waters told the AP he was aware of other contenders for the oldest projectile points found in North America, but he contends there have been flaws in how the claims were substantiated. His findings are supported by the geological layer where his points were found, how they were dated, and the shape and style of the points, he said. </s> Ancient tools that may give historians a glimpse into America's history were recently discovered just feet below the surface in Texas. Researchers with Texas A&M University made the stunning discovery during a dig at the Debra L. Friedkin site, located just 40 miles northwest of Austin.

Archaeologists have been searching for artifacts at the site near Buttermilk Creek for more than a decade — but this may be their most important find yet.

Michael Waters, professor of anthropology and director of the Center for the Study of the First Americans at Texas A&M, and staff from Baylor University and the University of Texas described the various ancient items they found in a study published in the latest issue of Science Advances. The team reveals they found 3 to 4-inch weapons, including spear points made of chert, under sediment they believe to be at least 15,500 years old.

“The discovery is significant because almost all pre-Clovis sites have stone tools, but spear points have yet to be found. These points were found under a layer with Clovis and Folsom projectile points," Waters said in a statement Wednesday, noting the term Clovis describes tools used by people 13,000 years ago. "The dream has always been to find diagnostic artifacts — such as projectile points — that can be recognized as older than Clovis and this is what we have at the Friedkin site.”

The Clovis people invented the "Clovis point," a spear-like weapon which has been discovered in portions of the U.S. and Mexico. For decades, the Clovis population was considered the first people to enter the North American continent, according to Science Daily.

Like the Clovis point, Waters believes the 15,000-year-old weapons recently uncovered in Austin were used to hunt large animals. Their existence may further support evidence that shows the first American settlers came to the country earlier than historians previously thought.

"Over the past decade, genetic studies of modern Native Americans and prehistoric skeletons have shown that the initial movement of people south of the continental ice sheets occurred as early as ~15 to ~16 ka ago and that there is genetic continuity between the first immigrants to enter the Americas and modern Native Americans," authors of the research explained. "Archaeological studies over the last 25 years show that people successfully occupied the Americas ~14 to ~15 ka ago, in agreement with the genetic estimates."

However, Waters admits there's still a lot of research to be done in regard to the tools to gain better insight into the people who roamed North America back then.

“The findings expand our understanding of the earliest people to explore and settle North America,” Waters said. “The peopling of the Americas during the end of the last Ice Age was a complex process and this complexity is seen in their genetic record. Now we are starting to see this complexity mirrored in the archaeological record.” </s> Ancient weapons found in Texas could be the oldest ever found in North America by 2,500 years - and could shed new light on how mankind came to the continent.

The 'numerous' weapons found 40 miles northwest of Austin could point to two separate migrations into North America - one earlier than previously known, researchers say.

Spear points made of chert and other tools were discovered under several feet of sediment that dating revealed to be 15,500 years old, and pre-date Clovis, who for decades were believed to be the first people to enter the Americas.

However, some researchers have questioned the dating methods used.

Researchers have identified a particular style of projectile point – or triangular blade often attached to a weapon that would be thrown – dated between 13,500 and 15,500 years ago, they say. This is earlier than typical Clovis-style technologies dated to 13,000 years ago. The finding suggests that projectile points changed over time from the stemmed form found here into the more widespread, Clovis-style lanceolate fluted projectile point. It's also possible, say the study's authors, that the projectile point style they found in Texas is a distinct style created by people of an earlier, separate migration into the Americas.

'There is no doubt these weapons were used for hunting game in the area at that time,' said Michael Waters, distinguished professor of anthropology and director of the Center for the Study of the First Americans at Texas A&M, who led the research.

'The findings expand our understanding of the earliest people to explore and settle North America.'

It's also possible, say the study's authors, that the projectile point style they found in Texas is actually a distinct style created by people of an earlier, separate migration into the Americas.

Researchers found a style of projectile point often attached to a weapon that would be thrown, dated between 13,500 and 15,500 years ago.

This is earlier than typical Clovis-style technologies dated to 13,000 years ago.

Clovis is the name given to the distinctive tools made by people starting around 13,000 years ago.

The Clovis people invented the 'Clovis point,' a spear-shaped weapon made of stone that is found in Texas and parts of the United States and northern Mexico and the weapons were made to hunt animals, including mammoths and mastodons, from 13,000 to 12,700 years ago.

'Given the age of the Debra L. Friedkin site—early people carrying stemmed points likely arrived by entering the Americas along the Pacific coast,' Waters told Gizmodo.

'Later lanceolate point forms like Clovis may have developed from the stemmed point forms or a second migration of people carried some sort of lanceolate point, like the triangular lanceolate form we found at the Friedkin site, and this developed into Clovis.'

'The dream has always been to find diagnostic artifacts – such as projectile points – that can be recognized as older than Clovis and this is what we have at the Friedkin site,' Water said in a statement.

'The peopling of the Americas during the end of the last Ice Age was a complex process and this complexity is seen in their genetic record.

'Now we are starting to see this complexity mirrored in the archaeological record.'

However, some researchers have questioned the dating techniques.

Ben Potter, an archaeologist from the University of Alaska Fairbanks said radiocarbon dating on cultural elements and artifacts would provide 'more precise and secure chronology.'

The team say from 19 optically stimulated luminescence dates of sediments, they determined the artifacts were between 13,500- and 15,500- years-old.

Waters and his team say that once developed, the lanceolate fluted point technology (associated with Clovis) could have spread over much of North America into northern Mexico, or alternatively, the stemmed and lanceolate point traditions may be evidence of two separate human migrations into North America

Waters and colleagues from Baylor University and the University of Texas have had their work published in the current issue of Science Advances. </s> For many years the consensus among archaeologists was that humans began settling in North America around 13,000 years ago. This timeline was based on artifacts found that dated back between 12,700 and 13,000 years, including weapons. Now, a new discovery in Texas could throw that theory right out the door.

Researchers from Texas A&M, Baylor University, and the University of Texas have uncovered what they believe to be spear points that were used by human hunters as far back as 15,500 years ago. The discovery pre-dates the accepted timeline for the settlement of North America by a significant margin, and scientists may be forced to rethink when and where the first groups of humans pushed into what is now the United States.

“There is no doubt these weapons were used for hunting game in the area at that time,” Michael Waters of Texas A&M, lead author of the paper published in Science Advances, said in a statement. “The discovery is significant because almost all pre-Clovis sites have stone tools, but spear points have yet to be found. These points were found under a layer with Clovis and Folsom projectile points. Clovis is dated to 13,000 to 12,700 years ago and Folsom after that. The dream has always been to find diagnostic artifacts – such as projectile points – that can be recognized as older than Clovis and this is what we have at the Friedkin site.”

It’s thought that hunting was what drove groups of ancient peoples into new areas, and at the time the spear points may have been used in hunting efforts against large game like mammoths. However, it wasn’t as though settlers of the age had maps or even a vague understanding of how the continent was shaped. They would have had little knowledge of what lied over the horizon as they traveled north, and wouldn’t have relocated unless it was necessary.

With that in mind, it’s easy to see why determining when human settlers arrived is such a difficult task. Smaller groups may have come and gone over time, and progress would have been slow. Whether this new discovery represents a large-scale movement into North America far earlier than was previously known, or if it’s nothing more than a bizarre outlier, remains to be seen. </s> Ancient weapons found in Texas could be the oldest ever found in North America by 2,500 years - and could shed new light on how mankind came to the continent.

The 'numerous' weapons found 40 miles northwest of Austin could point to two separate migrations into North America - one earlier than previously known, researchers say.

Spear points made of chert and other tools were discovered under several feet of sediment that dating revealed to be 15,500 years old, and pre-date Clovis, who for decades were believed to be the first people to enter the Americas.

However, some researchers have questioned the dating methods used.

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A 15,000-year-old stemmed point: Researchers found a style of projectile point often attached to a weapon that would be thrown, and dated it between 13,500 and 15,500 years ago

WHAT THEY FOUND Researchers have identified a particular style of projectile point – or triangular blade often attached to a weapon that would be thrown – dated between 13,500 and 15,500 years ago, they say. This is earlier than typical Clovis-style technologies dated to 13,000 years ago. The finding suggests that projectile points changed over time from the stemmed form found here into the more widespread, Clovis-style lanceolate fluted projectile point. It's also possible, say the study's authors, that the projectile point style they found in Texas is a distinct style created by people of an earlier, separate migration into the Americas.

'There is no doubt these weapons were used for hunting game in the area at that time,' said Michael Waters, distinguished professor of anthropology and director of the Center for the Study of the First Americans at Texas A&M, who led the research.

'The findings expand our understanding of the earliest people to explore and settle North America.'

It's also possible, say the study's authors, that the projectile point style they found in Texas is actually a distinct style created by people of an earlier, separate migration into the Americas.

Researchers found a style of projectile point often attached to a weapon that would be thrown, dated between 13,500 and 15,500 years ago.

This is earlier than typical Clovis-style technologies dated to 13,000 years ago.

Clovis is the name given to the distinctive tools made by people starting around 13,000 years ago.

The Clovis people invented the 'Clovis point,' a spear-shaped weapon made of stone that is found in Texas and parts of the United States and northern Mexico and the weapons were made to hunt animals, including mammoths and mastodons, from 13,000 to 12,700 years ago.

Excavations at the Debra L. Friedkin site in 2016: Spear points made of chert and other tools were discovered under several feet of sediment that dating revealed to be 15,500 years old, and pre-date Clovis, who for decades were believed to be the first people to enter the Americas.

The team say from 19 optically stimulated luminescence dates of sediments, they determined the artifacts were between 13,500- and 15,500- years-old.

'Given the age of the Debra L. Friedkin site—early people carrying stemmed points likely arrived by entering the Americas along the Pacific coast,' Waters told Gizmodo.

'Later lanceolate point forms like Clovis may have developed from the stemmed point forms or a second migration of people carried some sort of lanceolate point, like the triangular lanceolate form we found at the Friedkin site, and this developed into Clovis.'

'The dream has always been to find diagnostic artifacts – such as projectile points – that can be recognized as older than Clovis and this is what we have at the Friedkin site,' Water said in a statement.

'The peopling of the Americas during the end of the last Ice Age was a complex process and this complexity is seen in their genetic record.

'Now we are starting to see this complexity mirrored in the archaeological record.'

However, some researchers have questioned the dating techniques.

The Buttermilk Creek Complex is known to have been home to a group of Clovis people, but in recent years scientists have turned up evidence to suggest the presence of human settlement that predates the Clovis culture.

HOW DID OUR ANCESTORS FIRST REACH THE AMERICAS? The conventional story says that the earliest settlers came via Siberia, crossing the now-defunct Bering land bridge on foot and trekking through Canada. In recent years, evidence has mounted against the conventional thinking that humans populated North America by taking an inland route through Canada. To do so, they would have needed to walk through a narrow, ice-free ribbon of terrain that appeared when two major ice sheets started to separate. But recent research suggests that while this path may have opened up more than 14,000 years ago, it did not develop enough biological diversity to support human life until about 13,000 years ago. That clashes with archaeological findings that suggest humans were already living in Chile about 15,000 years ago or more and in Florida 14,500 years ago. Scientists now believe the first Americans could have taken a coastal route along Alaska's Pacific border to enter the continent. This theory provides an alternative narrative and could mark a step toward solving the mystery of how humans came to the Americas. By analysing boulders and bedrock, researchers from the University at Buffalo say they have 'direct evidence' that part of a coastal migration route along Alaska's Pacific became accessible to humans 17,000 years ago. During this period, ancient glaciers receded, exposing islands of southern Alaska's Alexander. The area was home to food sources such as ancient ringed seal that could support human life at the time that early settlers may have been passing through. Recent genetic and archaeological estimates suggest that settlers may have begun travelling deeper into the Americas some 16,000 years ago, soon after the coastal gateway opened up.

Ben Potter, an archaeologist from the University of Alaska Fairbanks said radiocarbon dating on cultural elements and artifacts would provide 'more precise and secure chronology.'

The team say from 19 optically stimulated luminescence dates of sediments, they determined the artifacts were between 13,500- and 15,500- years-old.

Waters and his team say that once developed, the lanceolate fluted point technology (associated with Clovis) could have spread over much of North America into northern Mexico, or alternatively, the stemmed and lanceolate point traditions may be evidence of two separate human migrations into North America

Waters and colleagues from Baylor University and the University of Texas have had their work published in the current issue of Science Advances. </s> In the winter of 1992, a construction crew in San Diego, California started cutting into the rocks that flanked the State 54 Highway, in a bid to widen the road. Those rocks hailed from the Pleistocene period and were rich in Ice Age fossils, so scientists from the San Diego Museum of Natural History accompanied the crew to recover whatever they unearthed. Among bits of horse, camel, dire wolf, and ground sloth, they found the remains of a single mastodon—an extinct mammoth-like animal. “And we noticed there was something different about it,” says Thomas Deméré, who was part of the team. Based on several lines of evidence—the way the bones are broken, the way they lay, the presence of large stones that show curious patterns of wear and are out-of-place in the surrounding sediment—the team think that early humans used rocks to hammer their way into the mastodon’s bones. That wouldn’t have been contentious in itself, but the team also claims that the bones from the “Cerruti Mastodon” are 130,000 years old. That would push back the earliest archaeological evidence for humans in North America by a whopping 115,000 years.

To put that in perspective, for decades, the first American settlers were thought to be the Clovis people, who arrived 13,000 years ago. But by discovering older sites with strong evidence of human activity, archaeologists confirmed that the continent had a pre-Clovis presence that dates back 14,600 years—or perhaps even further. Genetic studies have also suggested that modern humans entered America from Asia even earlier, around 23,000 years ago. Each of these claims was a bold one. “We archaeologists had a tough-enough time accepting that there are sites in the Americas greater than 13,000 years old—and a few of us still haven’t accepted that,” says Bonnie Pitblado from the University of Oklahoma. “But 130,000 years—ten times that far back in prehistory? That’s an enormous leap for a profession that, for all its focus on changes in human culture through time, really does not like to change its views.” “If the authors are correct, it would completely rewrite our best understanding of the peopling of the Americas,” says Jon Erlandson from the University of Oregon. “As scientists we're supposed to keep an open mind, but I doubt that many archaeologists will be convinced by this case. Extraordinary claims require extraordinary evidence, and I didn't find it here.” David Meltzer from Southern Methodist University concurs. “If you are going to push human antiquity in the New World back more than 100,000 years in one fell swoop, you’ll have to do so with a far better archaeological case than this one,” he says.

Most of the experts I spoke to weren’t convinced by the presented evidence, and some were downright disdainful. “I was astonished, not because it is so good but because it is so bad,” says Donald Grayson from the University of Washington. But not everyone is ready to dismiss the study yet. “This paper is a fantastic hypothesis,” says Zeray Alemseged from the University of Chicago. If the team is right, the perpetrators who broke the mastodon couldn’t possibly have been Homo sapiens, since our species hadn’t left Africa 130,000 years ago. But at the time, the planet was full of other hominids, including Homo Erectus, Neanderthals, Denisovans, and the “hobbits” of Flores. “Could it be that some of them ventured into North America, back then? Why not? Could there have been another species of Homo hanging out in California? Knowing how migratory our genus is I wouldn’t be surprised.” “I think they’ve have made a very strong case,” says Pitblado. “They presented compelling evidence that doesn’t make this site a slam dunk, but must be taken seriously. I predict that most archaeologists will roll their eyes. What they’re unlikely to do is give the site a chance.” 

 A schematic of the Cerruit mastodon, showing recovered bones and teeth. Dan Fisher & Adam Rountrey, University of Michigan. Since 1993, the team, including lead author Steven Holen, have repeatedly tried to date the mastodon fragments, using techniques like carbon-dating. They repeatedly failed. They only succeeded when they turned to uranium-thorium dating, which looks at the decay of two radioactive elements. That gave an age of 130,700 years, give or take 9,400 in either direction. None of the people I contacted raised issues with those dates, but the team’s other clues are more controversial.

They found the mastodon’s bones in a couple of concentrated clusters rather than in a scattered mess. The tops of both thigh-bones had broken off and were lying side-by-side, amid a concentration of other bones. One of the tusks was lying horizontally in the sediment, the other was sticking up vertically. The team think that the remains of a naturally decaying mastodon wouldn’t have ended up in such distinctive patterns—and the bones of nearby bones of wolves and horses certainly didn’t. And although fragile bones like ribs and vertebrae were still intact, stronger ones like molars and thigh-bones were broken. The fractures aren’t consistent with chewing teeth or trampling feet; instead they look like the breaks you get when you deliberately smash a still-living bone. The team even tried doing this: they smacked modern elephant and cow bones with rocks, and got fractures very similar to the ones on the Cerruti mastodon. At the site, the team found five large stones (cobbles) amid their clusters of bones, which could have acted as hammers and anvils. These rocks sat in a layer of fine, silt-like sediment, and were far bigger and harder than anything around them. “How did they get there?” says Deméré. “They weren’t being transported by flowing water at the same time as the silt.” Instead, he suggests that they were carried to the site and used to infiltrate the mastodon bones—presumably to get at the marrow within. Sure enough, the rocks showed signs of impact, and the team even managed to fit several detached flakes back onto the “parent” stones.

Could these patterns have been caused by anything else? Could the bones have been trampled by heavy feet, chewed or crunched by scavengers, or displaced and eroded by water? “I cannot envision another scenario than human involvement that introduces heavy mastodon bones, lighter mastodon bones, and heavy cobbles into an otherwise well-sorted, fine-grained matrix,” says Pitblado. And Deméré adds that his team took care to rule out alternative explanations. “It’s the totality of the site—all these different lines of evidence that can’t be explained by processes other than human activity,” he says. But “nature is mischievous and can break bones and modify stones in a myriad of ways,” says Meltzer, who thinks that the evidence is “inherently ambiguous.” Ariane Burke from the University of Montreal adds that the fractures are consistent with the bones having been struck by a heavy object while still fresh—but it’s not clear if humans did the striking. The problem is that in focusing on the fractures, the team haven’t published information on the rest of the bones, which might reveal signs of weathering or other natural abrasions. “It is one thing to show that broken bones and modified rocks could have been produced by people, which they’ve done,” says Grayson. “It is quite another to show that people, and people alone, could have produced those modifications. This they have most certainly not done, making this a very easy claim to dismiss.”

Even if Holen, Deméré, and their colleagues are right, why has no one else found any trace of these bone-smashing pioneers? “Where are the clearly recognizable artifacts that hominins throughout the Old World were making 130,000 years ago?” says Erlandson. “And if people were in California at this time, what happened to them for the next 100,000 years?” Deméré can only speculate. Perhaps these people represented a failed attempt to colonize the New World—they arrived but eventually disappeared, leaving a hominid-less window of time before others entered America much later. And “maybe archaeologists just aren’t looking in 130,000-year-old rocks for evidence of humans,” he says. “You have to ask the question first. Maybe sites like this have been found but haven’t been recognized for what they are.” But “it’s unlikely that archaeologists have missed these sites, as people have been looking for Pre-Clovis for decades and other paleontological sites for the past century,” says Lauren Norman from Kansas University. And how, she wonders, did these hypothetical pioneers even get to North America? “They would have had to have either go by boat, or travel through the Bering Strait. There is very little evidence for long-distance boating technology at this time. And if people traversed the Bering Strait during a glacial period, they would have had to have Arctic adaptations. The earliest evidence of people using the Arctic is around 40,000 years ago.” “Scientific claims of this magnitude require far more than plausibility.” Controversies like this aren’t new. In the late 70s, researchers suggested that stone artifacts in California’s Calico Hills were 200,000-year-old tools—but others argued that they were likely shaped through natural processes. Another group of Californian artifacts, also recovered near San Diego, were billed as 125,000-year-old grinding stones, and that claim was also discredited for similar reasons. “The North American archaeological literature is full of claims like this,” says Grayson. “There is no reason to think that this new one will receive a different professional reaction.”

When I asked him what level of evidence he would need to be convinced, he admits that the Cerruti team is in a tough situation. “There’s probably a nearly-infinite set of natural processes that could produce damage of this sort and no one could reasonably be expected to eliminate all of them,” he says. “The kinds of damage they illustrate are known to occur in non-archaeological settings, often from unknown processes. This might seem unfair—unknown processes are, by definition, impossible to eliminate—but scientific claims of this magnitude require far more than plausibility.” Michael Waters from Texas A&M University would be more convinced by the presence of “unequivocal stone tools.” Those might include knapped stones used to cut bone and butcher meat. But “If you think of this as an expedient site for processing bone, where you break it and cart it off somewhere else, there’s really no reason for refined tools,” says Deméré. “It’s not a butchery site.” Burke says that she’s like to see them “compare their bone assemblage to those of a similar age, where we know humans were exploiting mammoths in Eurasia.” And Alemseged thinks that it might not be possible to settle the debate unless someone finds fossils of these hypothetical pioneering hominids. “We need bones to really finalize this business,” he says.
Stone tools are found in Texas dating back 15,000 years, being the oldest evidence of humans in North America.