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News Article | April 26, 2017
Site: hosted2.ap.org

Neanderthals in California? Maybe so, provocative study says In this April 28, 1993 photo provided by the San Diego Natural History Museum, a bulldozer refills the Cerutti Mastodon site in San Diego, Calif., after the excavation and salvage of fossils. In a report released on Wednesday, April 26, 2017, researchers say the southern California site shows evidence of human-like behavior from about 130,000 years ago, when bones and teeth of an elephant-like mastodon were evidently smashed with rocks. (San Diego Natural History Museum via AP) In this April 28, 1993 photo provided by the San Diego Natural History Museum, a bulldozer refills the Cerutti Mastodon site in San Diego, Calif., after the excavation and salvage of fossils. In a report released on Wednesday, April 26, 2017, researchers say the southern California site shows evidence of human-like behavior from about 130,000 years ago, when bones and teeth of an elephant-like mastodon were evidently smashed with rocks. (San Diego Natural History Museum via AP) This Jan. 25, 1993 photo provided by the San Diego Natural History Museum shows a concentration of fossil bone and rock at an excavation site in San Diego, Calif. The positions of the femur heads, one up and one down, broken in the same manner next to each other is unusual. Mastodon molars are located in the lower right hand corner next to a large rock comprised of andesite which is in contact with a broken vertebra. At upper left is a rib angled upwards resting on a rock fragment. (San Diego Natural History Museum via AP) In this February 1993 photo provided by the San Diego Natural History Museum, San Diego Natural History Museum paleontologists C. Paul Majors and Matt Colbert work at the Cerutti Mastodon site in San Diego, Calif. In a report released on Wednesday, April 26, 2017, researchers say the southern California site shows evidence of human-like behavior from about 130,000 years ago, when bones and teeth of an elephant-like mastodon were evidently smashed with rocks. (San Diego Natural History Museum via AP) (AP) — A startling new report asserts that the first known Americans arrived much, much earlier than scientists thought — more than 100,000 years ago __ and maybe they were Neanderthals. If true, the finding would far surpass the widely accepted date of about 15,000 years ago. Researchers say a site in Southern California shows evidence of humanlike behavior from about 130,000 years ago, when bones and teeth of an elephantlike mastodon were evidently smashed with rocks. The earlier date means the bone-smashers were not necessarily members of our own species, Homo sapiens. The researchers speculate that these early Californians could have instead been species known only from fossils in Europe, Africa and Asia: Neanderthals, a little-known group called Denisovans, or another human forerunner named Homo erectus. "The very honest answer is, we don't know," said Steven Holen, lead author of the paper and director of the nonprofit Center for American Paleolithic Research in Hot Springs, South Dakota. No remains of any individuals were found. Whoever they were, they could have arrived by land or sea. They might have come from Asia via the Beringea land bridge that used to connect Siberia to Alaska, or maybe come across by watercraft along the Beringea coast or across open water to North America, before turning southward to California, Holen said in a telephone interview. Holen and others present their evidence in a paper released Wednesday by the journal Nature . Not surprisingly, the report was met by skepticism from other experts who don't think there is enough proof. The research dates back to the winter of 1992-3. The site was unearthed during a routine dig by researchers during a freeway expansion project in San Diego. Analysis of the find was delayed to assemble the right expertise, said Tom Demere, curator of paleontology at the San Diego Natural History Museum, another author of the paper. The Nature analysis focuses on remains from a single mastodon, and five stones found nearby. The mastodon's bones and teeth were evidently placed on two stones used as anvils and smashed with three stone hammers, to get at nutritious marrow and create raw material for tools. Patterns of damage on the limb bones looked like what happened in experiments when elephant bones were smashed with rocks. And the bones and stones were found in two areas, each roughly centered on what's thought to be an anvil. The stones measured about 8 inches (20 centimeters) to 12 inches (30 centimeters) long and weighed up to 32 pounds (14.5 kilograms). They weren't hand-crafted tools, Demere said. The users evidently found them and brought them to the site. The excavation also found a mastodon tusk in a vertical position, extending down into older layers, which may indicate it had been jammed into the ground as a marker or to create a platform, Demere said. The fate of the visitors is not clear. Maybe they died out without leaving any descendants, he said. Experts not connected with the study provided a range of reactions. "If the results stand up to further scrutiny, this does indeed change everything we thought we knew," said Chris Stringer of the Natural History Museum in London. Neanderthals and Denisovans are the most likely identities of the visitors, he said. Denisovans, more closely related to Neanderthals than to us, are known from fossils found in a Siberian cave. But "many of us will want to see supporting evidence of this ancient occupation from other sites, before we abandon the conventional model of a first arrival by modern humans within the last 15,000 years," he wrote in an email. Erella Hovers of the Hebrew University of Jerusalem and the Institute of Human Origins at Arizona State University in Tempe, who wrote a commentary accompanying the work, said in an email that the archaeological interpretation seemed convincing. Some other experts said the age estimate appears sound. But some were skeptical that the rocks were really used as tools. Vance Holliday of the University of Arizona in Tucson said the paper shows the bones could have been broken the way the authors assert, but they haven't demonstrated that's the only way. Richard Potts of the Smithsonian Institution's National Museum of Natural History, said he doesn't reject the paper's claims outright, but he finds the evidence "not yet solid." For one thing, the dig turned up no basic stone cutting tools or evidence of butchery or the use of fire, as one might expect from Homo sapiens or our close evolutionary relatives. The lead author, Holen, told reporters Tuesday that he and co-authors were ready for such criticism. "We expected skepticism because of the extremely old age of this site," he said. "I think we made a very good case." Copyright 2017 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.


News Article | April 26, 2017
Site: hosted2.ap.org

Neanderthals in California? Maybe so, provocative story says In this April 28, 1993 photo provided by the San Diego Natural History Museum, a bulldozer refills the Cerutti Mastodon site in San Diego, Calif., after the excavation and salvage of fossils. In a report released on Wednesday, April 26, 2017, researchers say the southern California site shows evidence of human-like behavior from about 130,000 years ago, when bones and teeth of an elephant-like mastodon were evidently smashed with rocks. (San Diego Natural History Museum via AP) In this April 28, 1993 photo provided by the San Diego Natural History Museum, a bulldozer refills the Cerutti Mastodon site in San Diego, Calif., after the excavation and salvage of fossils. In a report released on Wednesday, April 26, 2017, researchers say the southern California site shows evidence of human-like behavior from about 130,000 years ago, when bones and teeth of an elephant-like mastodon were evidently smashed with rocks. (San Diego Natural History Museum via AP) This Jan. 25, 1993 photo provided by the San Diego Natural History Museum shows a concentration of fossil bone and rock at an excavation site in San Diego, Calif. The positions of the femur heads, one up and one down, broken in the same manner next to each other is unusual. Mastodon molars are located in the lower right hand corner next to a large rock comprised of andesite which is in contact with a broken vertebra. At upper left is a rib angled upwards resting on a rock fragment. (San Diego Natural History Museum via AP) In this February 1993 photo provided by the San Diego Natural History Museum, San Diego Natural History Museum paleontologists C. Paul Majors and Matt Colbert work at the Cerutti Mastodon site in San Diego, Calif. In a report released on Wednesday, April 26, 2017, researchers say the southern California site shows evidence of human-like behavior from about 130,000 years ago, when bones and teeth of an elephant-like mastodon were evidently smashed with rocks. (San Diego Natural History Museum via AP) (AP) — A startling new report asserts that the first known Americans arrived much, much earlier than scientists thought — more than 100,000 years ago __ and maybe they were Neanderthals. If true, the finding would far surpass the widely accepted date of about 15,000 years ago. Researchers say a site in Southern California shows evidence of humanlike behavior from about 130,000 years ago, when bones and teeth of an elephantlike mastodon were evidently smashed with rocks. The earlier date means the bone-smashers were not necessarily members of our own species, Homo sapiens. The researchers speculate that these early Californians could have instead been species known only from fossils in Europe, Africa and Asia: Neanderthals, a little-known group called Denisovans, or another human forerunner named Homo erectus. "The very honest answer is, we don't know," said Steven Holen, lead author of the paper and director of the nonprofit Center for American Paleolithic Research in Hot Springs, South Dakota. No remains of any individuals were found. Whoever they were, they could have arrived by land or sea. They might have come from Asia via the Beringea land bridge that used to connect Siberia to Alaska, or maybe come across by watercraft along the Beringea coast or across open water to North America, before turning southward to California, Holen said in a telephone interview. Holen and others present their evidence in a paper released Wednesday by the journal Nature . Not surprisingly, the report was met by skepticism from other experts who don't think there is enough proof. The research dates back to the winter of 1992-3. The site was unearthed during a routine dig by researchers during a freeway expansion project in San Diego. Analysis of the find was delayed to assemble the right expertise, said Tom Demere, curator of paleontology at the San Diego Natural History Museum, another author of the paper. The Nature analysis focuses on remains from a single mastodon, and five stones found nearby. The mastodon's bones and teeth were evidently placed on two stones used as anvils and smashed with three stone hammers, to get at nutritious marrow and create raw material for tools. Patterns of damage on the limb bones looked like what happened in experiments when elephant bones were smashed with rocks. And the bones and stones were found in two areas, each roughly centered on what's thought to be an anvil. The stones measured about 8 inches (20 centimeters) to 12 inches (30 centimeters) long and weighed up to 32 pounds (14.5 kilograms). They weren't hand-crafted tools, Demere said. The users evidently found them and brought them to the site. The excavation also found a mastodon tusk in a vertical position, extending down into older layers, which may indicate it had been jammed into the ground as a marker or to create a platform, Demere said. The fate of the visitors is not clear. Maybe they died out without leaving any descendants, he said. Experts not connected with the study provided a range of reactions. "If the results stand up to further scrutiny, this does indeed change everything we thought we knew," said Chris Stringer of the Natural History Museum in London. Neanderthals and Denisovans are the most likely identities of the visitors, he said. But "many of us will want to see supporting evidence of this ancient occupation from other sites, before we abandon the conventional model of a first arrival by modern humans within the last 15,000 years," he wrote in an email. Erella Hovers of the Hebrew University of Jerusalem and the Institute of Human Origins at Arizona State University in Tempe, who wrote a commentary accompanying the work, said in an email that the archaeological interpretation seemed convincing. Some other experts said the age estimate appears sound. But some were skeptical that the rocks were really used as tools. Vance Holliday of the University of Arizona in Tucson said the paper shows the bones could have been broken the way the authors assert, but they haven't demonstrated that's the only way. Richard Potts of the Smithsonian Institution's National Museum of Natural History, said he doesn't reject the paper's claims outright, but he finds the evidence "not yet solid." For one thing, the dig turned up no basic stone cutting tools or evidence of butchery or the use of fire, as one might expect from Homo sapiens or our close evolutionary relatives. The lead author, Holen, told reporters Tuesday that he and co-authors were ready for such criticism. "We expected skepticism because of the extremely old age of this site," he said. "I think we made a very good case." Copyright 2017 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.


News Article | April 26, 2017
Site: hosted2.ap.org

Neanderthals in California? Maybe so, provocative study says In this April 28, 1993 photo provided by the San Diego Natural History Museum, a bulldozer refills the Cerutti Mastodon site in San Diego, Calif., after the excavation and salvage of fossils. In a report released on Wednesday, April 26, 2017, researchers say the southern California site shows evidence of human-like behavior from about 130,000 years ago, when bones and teeth of an elephant-like mastodon were evidently smashed with rocks. (San Diego Natural History Museum via AP) In this April 28, 1993 photo provided by the San Diego Natural History Museum, a bulldozer refills the Cerutti Mastodon site in San Diego, Calif., after the excavation and salvage of fossils. In a report released on Wednesday, April 26, 2017, researchers say the southern California site shows evidence of human-like behavior from about 130,000 years ago, when bones and teeth of an elephant-like mastodon were evidently smashed with rocks. (San Diego Natural History Museum via AP) This Jan. 25, 1993 photo provided by the San Diego Natural History Museum shows a concentration of fossil bone and rock at an excavation site in San Diego, Calif. The positions of the femur heads, one up and one down, broken in the same manner next to each other is unusual. Mastodon molars are located in the lower right hand corner next to a large rock comprised of andesite which is in contact with a broken vertebra. At upper left is a rib angled upwards resting on a rock fragment. (San Diego Natural History Museum via AP) In this February 1993 photo provided by the San Diego Natural History Museum, San Diego Natural History Museum paleontologists C. Paul Majors and Matt Colbert work at the Cerutti Mastodon site in San Diego, Calif. In a report released on Wednesday, April 26, 2017, researchers say the southern California site shows evidence of human-like behavior from about 130,000 years ago, when bones and teeth of an elephant-like mastodon were evidently smashed with rocks. (San Diego Natural History Museum via AP) (AP) — A startling new report asserts that the first known Americans arrived much, much earlier than scientists thought — more than 100,000 years ago __ and maybe they were Neanderthals. If true, the finding would far surpass the widely accepted date of about 15,000 years ago. Researchers say a site in Southern California shows evidence of humanlike behavior from about 130,000 years ago, when bones and teeth of an elephantlike mastodon were evidently smashed with rocks. The earlier date means the bone-smashers were not necessarily members of our own species, Homo sapiens. The researchers speculate that these early Californians could have instead been species known only from fossils in Europe, Africa and Asia: Neanderthals, a little-known group called Denisovans, or another human forerunner named Homo erectus. "The very honest answer is, we don't know," said Steven Holen, lead author of the paper and director of the nonprofit Center for American Paleolithic Research in Hot Springs, South Dakota. No remains of any individuals were found. Whoever they were, they could have arrived by land or sea. They might have come from Asia via the Beringea land bridge that used to connect Siberia to Alaska, or maybe come across by watercraft along the Beringea coast or across open water to North America, before turning southward to California, Holen said in a telephone interview. Holen and others present their evidence in a paper released Wednesday by the journal Nature . Not surprisingly, the report was met by skepticism from other experts who don't think there is enough proof. The research dates back to the winter of 1992-3. The site was unearthed during a routine dig by researchers during a freeway expansion project in San Diego. Analysis of the find was delayed to assemble the right expertise, said Tom Demere, curator of paleontology at the San Diego Natural History Museum, another author of the paper. The Nature analysis focuses on remains from a single mastodon, and five stones found nearby. The mastodon's bones and teeth were evidently placed on two stones used as anvils and smashed with three stone hammers, to get at nutritious marrow and create raw material for tools. Patterns of damage on the limb bones looked like what happened in experiments when elephant bones were smashed with rocks. And the bones and stones were found in two areas, each roughly centered on what's thought to be an anvil. The stones measured about 8 inches (20 centimeters) to 12 inches (30 centimeters) long and weighed up to 32 pounds (14.5 kilograms). They weren't hand-crafted tools, Demere said. The users evidently found them and brought them to the site. The excavation also found a mastodon tusk in a vertical position, extending down into older layers, which may indicate it had been jammed into the ground as a marker or to create a platform, Demere said. The fate of the visitors is not clear. Maybe they died out without leaving any descendants, he said. Experts not connected with the study provided a range of reactions. "If the results stand up to further scrutiny, this does indeed change everything we thought we knew," said Chris Stringer of the Natural History Museum in London. Neanderthals and Denisovans are the most likely identities of the visitors, he said. But "many of us will want to see supporting evidence of this ancient occupation from other sites, before we abandon the conventional model of a first arrival by modern humans within the last 15,000 years," he wrote in an email. Erella Hovers of the Hebrew University of Jerusalem and the Institute of Human Origins at Arizona State University in Tempe, who wrote a commentary accompanying the work, said in an email that the archaeological interpretation seemed convincing. Some other experts said the age estimate appears sound. But some were skeptical that the rocks were really used as tools. Vance Holliday of the University of Arizona in Tucson said the paper shows the bones could have been broken the way the authors assert, but they haven't demonstrated that's the only way. Richard Potts of the Smithsonian Institution's National Museum of Natural History, said he doesn't reject the paper's claims outright, but he finds the evidence "not yet solid." For one thing, the dig turned up no basic stone cutting tools or evidence of butchery or the use of fire, as one might expect from Homo sapiens or our close evolutionary relatives. The lead author, Holen, told reporters Tuesday that he and co-authors were ready for such criticism. "We expected skepticism because of the extremely old age of this site," he said. "I think we made a very good case." Copyright 2017 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.


News Article | May 1, 2017
Site: www.futurity.org

Mastodon bones recovered from a site in San Diego appear to dramatically revise the timeline for when humans first reached North America. The bones, tusks, and molars are about 130,000 years old. They were sharply broken and found deeply buried alongside large stones that appeared to have been used as hammers and anvils. “This discovery is rewriting our understanding of when humans reached the New World. The evidence we found at this site indicates that some hominin species was living in North America 115,000 years earlier than previously thought,” says Judy Gradwohl, president and chief executive officer of the San Diego Natural History Museum, whose paleontology team discovered the fossils, managed the excavation, and incorporated the specimens into the museum’s research collection. “This raises intriguing questions about how these early humans arrived here and who they were.” Until recently, the oldest records of human sites in North America generally accepted by archaeologists were about 14,000 years old. But the fossils from the Cerutti Mastodon site (named in recognition of field paleontologist Richard Cerutti, who discovered the site and led the excavation) were found embedded in fine-grained sediments that had been deposited much earlier—during a period long before humans were thought to have arrived on the continent. “When we first discovered the site, there was strong physical evidence that placed humans alongside extinct Ice Age megafauna. This was significant in and of itself and a ‘first’ in San Diego County,” says Tom Deméré, curator of paleontology and director of PaleoServices at the San Diego Natural History Museum and corresponding author of the paper in Nature. “Since the original discovery, dating technology has advanced to enable us to confirm with further certainty that early humans were here much earlier than commonly accepted.” University of Michigan paleontologist Daniel Fisher, a coauthor of the paper, says several lines of evidence from the Cerutti Mastodon site point to “one interpretation that is almost unavoidable because of the way these different lines of argument interlace.” “We don’t know how this animal died. We don’t know whether humans were part of that death. All that we know is that humans came along some time after the death, and they very strategically set up a process involving the harvesting of marrow from the long bones and the recovery of dense fragments of bone that they could use as raw material for producing tools,” says Fisher, who has been excavating mammoths and mastodons in the Great Lakes region for 38 years and who has also worked on woolly mammoth remains in Siberia for about 20 years. Since its initial discovery in late 1992, the Cerutti Mastodon site has been the subject of research by top scientists to date the fossils accurately and evaluate microscopic damage on bones and rocks that authors now consider indicative of human activity. In 2014, James Paces, a research geologist with the US Geological Survey, used state-of-the-art radiometric dating methods to determine that the mastodon bones—which were still fresh when they were broken by strategically placed blows from hammerstones—were 130,000 years old, with a conservative error of plus or minus 9,400 years. “The distributions of natural uranium and its decay products both within and among these bone specimens show remarkably reliable behavior, allowing us to derive an age that is well within the wheelhouse of the dating system,” says Paces, a coauthor of the paper. The finding poses a lot more questions than answers: Who were these people? Are they part of an early—but failed—colonization attempt? Or is there a long, but as of yet, scarcely recognized presence of humans in this hemisphere? “There’s no doubt in my mind this is an archaeological site,” says Steve Holen, director of research at the Center for American Paleolithic Research, former curator of archaeology at the Denver Museum of Nature & Science, and lead author of the paper. “The bones and several teeth show clear signs of having been deliberately broken by humans with manual dexterity and experiential knowledge. “This breakage pattern has also been observed at mammoth fossil sites in Kansas and Nebraska, where alternative explanations such as geological forces or gnawing by carnivores have been ruled out.” Both Holen and Fisher have conducted experiments with the bones of large modern mammals, including elephants, to determine what it takes to break the bones with large hammerstones and to analyze the distinctive breakage patterns that result. “It’s this sort of work that has established how fractures like this can be made,” says Fisher. “And based on decades of experience seeing sites with evidence of human activity, and also a great deal of work on modern material trying to replicate the patterns of fractures that we see, I really know of no other way that the material of the Cerutti Mastodon site could have been produced than through human activity,” he adds. The specimens recovered from the Cerutti Mastodon site will be displayed at the San Diego museum beginning April 26, and a public lecture featuring several of the Nature article authors will take place April 29. Digital 3D models of a selection of specimens pointing toward human association at this site can be viewed interactively at the University of Michigan Online Repository of Fossils. Animations featuring these models are also presented as supplementary information associated with the Nature paper. Coauthor Adam Rountrey, collection manager at the University of Michigan Museum of Paleontology, led the effort to create the 3D digital models of bone and stone specimens from the Cerutti site. “The models were immensely helpful in interpreting and illustrating these objects,” he says. “We were able to put together virtual refits that allow exploration of how the multiple fragments from one hammerstone fit back together. The 3D models helped us understand what we were looking at and to communicate the information much more effectively. “I think the models are important in terms of supporting the paper because they allow anyone to look at this evidence in much the same way the coauthors did. It’s fine to be skeptical, but look at the evidence and judge for yourself. That’s what we’re trying to encourage by making these models available.” The National Geographic Society, the Walton Family Fund, Pat Boyce and Debbie Fritsch, the James Hervey Johnson Charitable Educational Trust, and the Downing Family Foundation supported the project.


News Article | April 27, 2017
Site: news.yahoo.com

Fossilised Mastodon bones could rewrite story of how humans colonised the world The discovery of the fossilised remains of an elephant-like animal on a construction site in San Diego appears to have entirely rewritten the story of humans’ colonisation of the world. For the 130,000-year-old mastodon bones had been smashed in a way that suggests people had used stones to break into the nutritious marrow inside – even though humans were not supposed to have arrived on the continent for another 115,000 years. Homo sapiens are thought to have still been in Africa at this time and the researchers said the type of human involved was “unidentified”. One expert suggested they could be Homo erectus, Neanderthals or Denisovans, but the newly discovered ‘hobbits’, Homo floresiensis, are not thought to be likely candidates. How they got there is another burning question. They might have crossed the land bridge that once linked east-Asia and Alaska, but it is also possible they sailed across an 80km stretch of ocean. The remains were found in 1992, but they could not be accurately dated until technological advances allowed this to happen in 2011. Now the researchers have published a paper about their work in the journal Nature as an exhibition about the findings opened at the San Diego Natural History Museum. In a video about the discovery, the museum said: “It took 22 years to piece the story of these fossils together. And the picture it reveals just might change everything.” When the remains were first found, experts from the museum thought they had simply discovered the remains of a dead mastodon. “But something was puzzling. Many of the bones were strangely fractures or missing entirely,” the museum said. “And there were several large stones that seemed out of place in the surrounding fine-grained sediments.” Ancestors of 'hobbits' may have been first humans to leave Africa Dr Steve Holen, of Denver Museum of Nature and Science, was brought in to examine the fractured fossils. “Using femur bones of recently deceased elephants, Holen had conducted two separate experiments in which he demonstrated that a stone used as a hammer causes fresh limb bones to fracture in a distinctive way,” the museum said. “No known geological process or animal scavenging produces the same fractures in bones.” Another expert was then asked to examine the stones found near the fossils. “The large stones showed the same abrasions, fractures and scars that only occur in stones used as hammer stones and anvils,” the museum added. It said the research raised fundamental questions about the human story. “Who were the humans at work at this site and how did they reach North America? Were they an early failed attempt to colonise a new part of the world?” the museum pondered in the video. In the Nature paper, the researchers said the dating technique suggested the remains were 130,000 years old, plus or minus about 9,400 years. “These findings confirm the presence of an unidentified species of Homo at the site during the last interglacial period, indicating that humans with manual dexterity and the experiential knowledge to use hammerstones and anvils processed mastodon limb bones for marrow extraction and/or raw material for tool production,” the paper said. “The site is, to our knowledge, the oldest in situ, well-documented archaeological site in North America and, as such, substantially revises the timing of arrival of Homo into the Americas.” An accompanying article by Professor Erella Hovers, an archaeologist at the Hebrew University of Jerusalem, said the “big surprise” was the site's age. “The finds … could place hominins in the New World more than 100,000 years earlier than previously thought,” she said. “The authors propose coastal entry, given claims that hominins reached Asian and Mediterranean islands more than 100,000 years ago. “They argue that, despite sea-level rise during the last interglacial, the distances to the Americas by water were within the capabilities of human populations at that time; the warm interglacial conditions would have facilitated adaptation to the newly discovered environment on land.” She suggested “late populations of Homo erectus”, Neanderthals or the “elusive” Denisovans may have butchered the mastodon. She noted that Dr Holen and colleagues “do not consider the insular Homo floresiensis as a probable early coloniser of America”. “What happened after these hominins reached the Americas? The archaeological record is silent until much more recent times,” Dr Hovers said. There have been other suggestions that humans were present in the Americas before 15,000 years ago, but the evidence has been inconclusive. But Dr Hovers said: “The evidence from the Cerutti Mastodon site has been rigorously researched and presented, and might be more difficult to refute, even though the proposed hominin narrative derived from these data has some gaping holes that need filling. “Time will tell whether this evidence will bring a paradigm change in our understanding of processes of hominin dispersal and colonisation throughout the world, including in what now seems to be a not-so-new New World.”


News Article | April 26, 2017
Site: www.bbc.co.uk

A study that claims humans reached the Americas 130,000 years ago - much earlier than previously suggested - has run into controversy. Humans are thought to have arrived in the New World no earlier than 25,000 years ago, so the find would push back the first evidence of settlement by more than 100,000 years. The conclusions rest on analysis of animal bones and tools from California. But many experts contacted by the BBC said they doubted the claims. Thomas Deméré, Steven Holen and colleagues examined material from the Cerutti Mastodon site near San Diego. The site was originally uncovered in 1992, during highway construction work. Possible stone tools were discovered alongside the smashed up remains of a mastodon (Mammut americanum) - an extinct relative of mammoths and living elephants. The researchers behind the latest study were unable to carry out radiocarbon dating on the remains, so they used a technique called uranium-thorium dating on several bone fragments, coming up with a date of 130,000 years. The team members found that some of the bones and teeth bore a characteristic breakage pattern known as spiral fracturing, considered to occur when the bone is fresh. Additionally, some of the bones showed typical signs of being smashed with hard objects. Rocks found alongside the mastodon remains show signs of wear and being struck against other surfaces, the researchers say. They conclude that these represent hammerstones and anvils - two types of stone tool used by prehistoric cultures. Dr Deméré, curator of palaeontology at the San Diego Natural History Museum, said the totality of evidence at the site had led team members to the conclusion that "humans were processing [working on or breaking up] mastodon limb bones using hammerstones and anvils and that the processing occurred at the site of burial 130,000 years ago". Dr Holen, co-director of the Center for American Paleolithic Research in South Dakota, commented: "We have conducted two experiments breaking elephant bones with large rock hammers and anvils. We produced exactly the same kind of fracture patterns as we found on the Cerutti mastodon limb bones." He added: "We can eliminate all of the natural processes that break bones like this. These bones were not broken by carnivore chewing, or by other animals trampling on this bone... the distribution patterns of the fractured pieces of bone right around the anvils is fairly conclusive evidence because we see that experimentally also." It's not entirely clear why early humans smashed up the mastodon bones. "We have no evidence that this is a kill or butchery site, but what we do have evidence of is that people were here breaking up the limb bones of this mastodon, removing some of the big thick pieces - probably to make tools out of - and they may also have been extracting the marrow for food," said Dr Holen. If the team's conclusions are correct, people could have reached the Americas from Asia via a land bridge across the Bering Strait. This bridge periodically emerged during cold periods - when ocean water was locked up as ice - and disappeared when the climate warmed again and sea levels rose. The earliest widely accepted evidence for humans in the Americas dates to roughly 15,000 years ago. This is a field where fierce debate has raged over rolling back the ages of human occupation by one or two thousand years, let alone 100,000. Dr Deméré and colleagues are not the first scientists to posit much earlier dates for people settling in the Americas. What distinguishes the latest work is that it has been published in one of the most prestigious peer-reviewed science journals in the world - Nature. However, other experts remain unconvinced by the new evidence. Prof Michael R Waters, from Texas A&M University in College Station, described the new paper as "provocative". He told BBC News the study "purports to provide evidence of human occupation of the Americas some 115,000 years before the earliest well established evidence". Prof Waters explained: "I have no issues with the geological information - although I would like to know more about the broader geological context - and the likely age of the locality. However, I am sceptical of the evidence presented that humans interacted with the mastodon at the Cerutti Mastodon site." "To demonstrate such early occupation of the Americas requires the presence of unequivocal stone artefacts. There are no unequivocal stone tools associated with the bones... this site is likely just an interesting paleontological locality." Prof Tom Dillehay, from Vanderbilt University in Nashville, Tennessee, told BBC News the claim was not plausible. Another authority on early American archaeology, Prof David Meltzer from Southern Methodist University in Dallas, Texas, said: "Nature is mischievous and can break bones and modify stones in a myriad of ways. "With evidence as inherently ambiguous as the broken bones and non-descript broken stones described in the paper, it is not enough to demonstrate they could have been broken/modified by humans; one has to demonstrate they could not have been broken by nature. "This is an equifinality problem: multiple processes can cause the same product." Chris Stringer, from London's Natural History Museum, said that "if the results stand up to further scrutiny, this does indeed change everything we thought we knew about the earliest human occupation of the Americas," adding: "If true, the results may well mean that archaic people like the Denisovans or Neanderthals were the first colonisers of the Americas, rather than modern humans." He explained that "extraordinary claims require extraordinary evidence - each aspect requires the strongest scrutiny," but Prof Stringer also observed: "High and concentrated forces must have been required to smash the thickest mastodon bones, and the low energy depositional environment seemingly provides no obvious alternative to humans using the heavy cobbles found with the bones." The dating method used by the researchers to assign an age to this material works by measuring the radioactive decay of uranium that becomes incorporated into the bones over time. "The type of samples that are most widely dated with this technique are ones that contain uranium as a primary substitution in their structure, such as inorganic carbonates, like cave carbonates, or corals, which take in uranium as they take calcium out of seawater," Dr Warren D Sharp, an expert in isotope dating from the Berkeley Geochronology Center in California, told BBC News. "What they've done in this paper is applied it to bone. That can be challenging because bones don't contain significant amounts of primary uranium. They acquire the uranium when they become buried - they take it up from soil porewaters." He added: "That said, I think the dating is sound. They have done a very careful job. They have dated multiple samples and obtained similar results. The systematics of the concentrations of uranium in profiles across the bones are what you'd expect for reliable dates. And the bones that they've dated seem to be an integral part of the site, so their age should be relevant to the rest of the observations." Prof Meltzer said the history of the material from the site meant it would be difficult to prove that humans broke the bones. He explained: "[The evidence] comes from a site that was excavated [approximately] 25 years ago as a salvage project during a highway expansion. "The kinds of detailed information necessary to understand how these bones and stones came to be... is simply not available. The authors do what they can with the extant collections, but they necessarily have to rely more on generalisations about what could (or could not) account for the evidence - which gets us back to the equifinality problem."


News Article | April 26, 2017
Site: www.csmonitor.com

—American history may have begun more than 100,000 years earlier than previously thought. At least that's what a team of scientists suggest in a paper published Wednesday in the journal Nature. The paper's authors point to an assemblage of broken mastodon bones and chipped rocks unearthed in southern California as evidence that a stone tool-wielding people snacked on the meat and marrow, or perhaps shaped tools out of the massive animal's skeleton, when it died some 130,000 years ago. Such a megafauna-human interaction from that period wouldn't have been shocking to find almost anywhere else in the world, as various archaic human species had already spread across much of the globe. But humans are thought to have first settled the Americas around 15,000 years ago, give or take a thousand years, not 100,000. Rewriting history is not an easy thing to do. The researchers' findings have been met with widespread skepticism, highlighting just how hard it is to reframe historical narratives. "It's an extraordinary claim. It would rewrite the prehistory of the Americas, and the prehistory of human migrations around the world," says Jon Erlandson, an archaeologist at the University of Oregon. Still, he says, "Extraordinary claims require extraordinary evidence, and I didn't find it here." But Thomas Deméré, a paleontologist at the San Diego Natural History Museum and one of the paper's authors, disagrees. "Of course extraordinary claims like this require extraordinary evidence and we feel that [this site] preserves such evidence," he said in a press conference. Skeptics largely suggest that the evidence for a hominin presence could too easily be explained away. For example, the authors point to spiral fractures in the bones as being key evidence of a hominin smashing the bones with hammerstones, which matches behavior thought to be associated with prehistoric humans in Africa at the time, and even tried smashing elephant bones themselves as a proxy. But Joseph Ferraro, an anthropologist at Baylor University who studies archaeological and paleontological materials across humanity’s history in East Africa, suggests that there may be another explanation. The research team ruled out another carnivore chewing or bashing the bones, but Dr. Ferraro says that proboscideans, a group that includes elephants, mammoths, mastodons, and other tusked megafauna, are known to have tussled, using their tusks and whacking each other's flanks. "It's not uncommon to get broken ribs, not uncommon to get broken legs, and so forth," he says. "That could easily result in a fracture, and if it results in the death of an individual, there's not going to be any signs of any healing," much like the breaks found on the mastodon that is the focus of this study. "You can spin so many different equally or more plausible stories about how and why this assemblage formed, without having to invoke any sort of hominin activity whatsoever," Ferraro says. So just what would it take for this discovery to revise the prehistory of the Americas? Although cutmarks and flaked stone tools would make this site more compelling, Ferraro says, all that is really needed would be one human fossil. If you had an unquestionably well-dated Homo erectus, or Neanderthal, or Denisovan, or even Homo sapiens bone, he says, then the prehistory books would certainly need to be rewritten. But, he says, "This is not that." The prehistory of the Americas has actually been rewritten before. For decades, archaeologists thought they knew exactly how and when humans first spread across the Americas. The story, called the Clovis-first model, had the Clovis people as the first population to spread south into the Americas from the region near the Bering land bridge when an ice-free corridor opened up through the middle of Canada, around 13,500 years ago at the earliest. As this model reigned, older archaeological sites, like an underwater 14,500-year-old site in Florida or a 15,000-year-old site in Chile, were dismissed as insufficient evidence. The thinking was that anything dating before the distinctive Clovis spearpoints showed up in the archaeological record couldn't possibly be evidence of a human presence. But as fresh evidence poured in from sites across the Americas, including genetic analysis, the Clovis-first model was eventually discarded and the history books were rewritten. Tom Dillehay, an anthropologist at Vanderbilt University, helped lead efforts countering the Clovis-first narrative through his work at the Monte Verde archaeological site in Chile. But, he says, although the San Diego site is a "classic early site" made up of bones and stones, the Monte Verde site also had other evidence pointing to a human presence, such as burned wood, knotted reeds, chunks of hide and meat, and even footprints. Dr. Dillehay advises that it's best to try to disprove any potentially history-shattering claims, rather than trying to prove them, saying it's a stronger way to rule out all the other possible explanations for the evidence. In the case of debunking the Clovis-first model, more archaeological sites bolstered the claim, and the same could help support Deméré and his colleagues' claim, too. There have been previous suggestions of such shockingly early human occupation of the Americas, similar to the current claim, Dr. Erlandson says. Items suggested to be artifacts of particularly ancient human settlements have been described from other sites in southern California, for example. But when this was proposed before, scientists went out looking for more evidence, Erlandson says, "And they never came up with anything convincing." Erlandson himself looked for evidence of human-caused fire, but was unable to find evidence that old scorched materials were the result of anything other than wildfires. Still, Steven Holen, lead author on the new paper, said in the press conference that he has already been looking for similar fractures in megafauna bones, which may have been overlooked by paleontologists who wouldn't have even considered a human impact at the time. Dr. Holen says evidence may have fallen through the cracks between archaeology and paleontology, as archaeologists wouldn't have been looking at materials this old before and paleontologists wouldn't have been considering a human factor when they examined the bones. But Ferraro says such an assertion isn't giving the experts enough credit. "There's a big literature out there on bone damage," he says. Paleontologists who devote their lives to studying bone damage can even identify something as specific as which species of termite once munched an old bone, he says, so he suspects paleontologists wouldn't have missed something as significant as evidence of human activity. Skeptics are also concerned about the bigger-picture implications of shifting the story of human occupation in the Americas so dramatically. "As scientists we're supposed to keep an open mind, but this discovery is hard to wrap my mind around because it falls so far beyond the realm of accepted knowledge," Erlandson says. "I'm not opposed to controversial theories," he says, "but if it's really 130,000 years ago, it just raises so many questions": for example, who those people were, where they came from, how they got there, and what happened in the subsequent 100,000 years. To answer that last question, the authors did suggest in the press conference that, like any other population of animals, this group of humans may have died out and therefore not left a trace in the years before the ancestors of today's Native Americans trekked across the land bridge from Siberia and spread across the region. Filling in the other gaps of the background story implied by Deméré, Holen, and colleagues' claim would require other extraordinary claims, Ferraro says. To explain how humans got to southern California would require a scenario such as one in which Homo erectus, Denisovans, or another archaic human species would have had to have been making boats in Siberia and following the coastline east, then down the western coast of the Americas, for example. And each detail needed to support such a tale, from whether they possessed boating technology to which archaic human species made the journey, would be an additional extraordinary claim in its own right, he says, which would in turn require its own set of extraordinary evidence. "It just requires so many individual extraordinary claims," Ferraro says. "It's not just one claim, but the whole argument is resting on a very shaky foundation." Perhaps eventually the prehistory books of the Americas will need to be revised to include a human presence 130,000 years ago, but first, Dillehay says, all other possible explanations need to be ruled out. "In other words," he says, the question must be asked: "Are we being fooled in this case once again?"


News Article | April 26, 2017
Site: www.sciencemag.org

What broke the 130,000-year-old mastodon bones in California? Most archaeologists would tell you it couldn’t have been humans, who didn’t leave conclusive evidence of their presence in the Americas until about 14,000 years ago. But a small group of experts now says that the fracture patterns on the bones, found during highway construction near San Diego, California, must have been left by humans pounding them with stones found nearby. If correct, the paper, published this week in , would push back the presence of people in the Americas by more than 100,000 years—to a time when modern humans supposedly had not even expanded out of Africa to Europe or Asia. “The claims made are extraordinary and the potential implications staggering,” says Jon Erlandson, an archaeologist at the University of Oregon in Eugene who studies the peopling of the Americas. “But broken bones and stones alone do not make a credible archaeological site in my view.” He and many other archaeologists say it will take much stronger evidence to convince them that the bones were fractured by ancient people. Archaeologists first excavated the Cerutti Mastodon site in 1992, after the construction exposed bones. Over time they found more splintered bones and a smattering of large round rocks embedded in otherwise fine-grained sediment. More recently, Daniel Fisher, a respected paleontologist at the University of Michigan in Ann Arbor, took a close look at the fractures and found patterns he says are consistent with blows from a rounded stone, which leave a characteristic notch at the point of impact. Other chips of bone show what he calls unmistakable signs of being popped off by the impact. “Nobody has ever explained those [characteristic bone flakes] satisfactorily in any way not involving human activity,” Fisher says. He says humans were probably breaking the bones to reach the marrow, or to turn the bone itself into a sharper tool. The nearby stones, hefty and round, show wear patterns consistent with being smashed against bone, the authors say. In experiments, they used that method to break elephant bones and produced identical fracture patterns. The bones’ collagen, a protein that can be used for radiocarbon dating, was long gone. Instead, the team relied on a dating technique based on the radioactive decay of uranium in minerals within the bone. Several dating experts said the methods were sound and found the 130,000-year date trustworthy. “At face value, these results are about as good as you can get,” says Alistair Pike, a uranium dating expert at the University of Southampton in the United Kingdom. But that still leaves the question of what splintered the bones. “It is one thing to show that broken bones and modified rocks could have been produced by people, which [this paper does],” says Don Grayson, an archaeologist at the University of Washington in Seattle. “It is quite another to show that people alone could have produced those modifications.” And Gary Haynes, an archaeologist at the University of Nevada in Reno, notes that “the features of the broken bones … are also produced when heavy construction equipment crushes buried bones.” Author and site excavator Thomas Deméré, a paleontologist at the San Diego Natural History Museum, says the team carefully excavated 50 square meters beginning in 1992, and the bones described in the paper were “deeply buried. … There was no equipment damage to the heart of the site.” The lack of actual shaped stone tools, a “universal” at Old World sites, troubles archaeologist John Shea of the State University of New York in Stony Brook. Even the archaic humans that might have been present then, like Homo erectus or the mysterious Denisovans, left such flakes. “This evidence is well documented, but it’s not sufficient to close the case,” Shea says.


News Article | April 26, 2017
Site: www.sciencemag.org

What broke the 130,000-year-old mastodon bones in California? Most archaeologists would tell you it couldn’t have been humans, who didn’t leave conclusive evidence of their presence in the Americas until about 14,000 years ago. But a small group of experts now says that the fracture patterns on the bones, found during highway construction near San Diego, California, must have been left by humans pounding them with stones found nearby. If correct, the paper, published this week in , would push back the presence of people in the Americas by more than 100,000 years—to a time when modern humans supposedly had not even expanded out of Africa to Europe or Asia. “The claims made are extraordinary and the potential implications staggering,” says Jon Erlandson, an archaeologist at the University of Oregon in Eugene who studies the peopling of the Americas. “But broken bones and stones alone do not make a credible archaeological site in my view.” He and many other archaeologists say it will take much stronger evidence to convince them that the bones were fractured by ancient people. Archaeologists first excavated the Cerutti Mastodon site in 1992, after the construction exposed bones. Over time they found more splintered bones and a smattering of large round rocks embedded in otherwise fine-grained sediment. More recently, Daniel Fisher, a respected paleontologist at the University of Michigan in Ann Arbor, took a close look at the fractures and found patterns he says are consistent with blows from a rounded stone, which leave a characteristic notch at the point of impact. Other chips of bone show what he calls unmistakable signs of being popped off by the impact. “Nobody has ever explained those [characteristic bone flakes] satisfactorily in any way not involving human activity,” Fisher says. He says humans were probably breaking the bones to reach the marrow, or to turn the bone itself into a sharper tool. The nearby stones, hefty and round, show wear patterns consistent with being smashed against bone, the authors say. In experiments, they used that method to break elephant bones and produced identical fracture patterns. The bones’ collagen, a protein that can be used for radiocarbon dating, was long gone. Instead, the team relied on a dating technique based on the radioactive decay of uranium in minerals within the bone. Several dating experts said the methods were sound and found the 130,000-year date trustworthy. “At face value, these results are about as good as you can get,” says Alistair Pike, a uranium dating expert at the University of Southampton in the United Kingdom. But that still leaves the question of what splintered the bones. “It is one thing to show that broken bones and modified rocks could have been produced by people, which [this paper does],” says Don Grayson, an archaeologist at the University of Washington in Seattle. “It is quite another to show that people alone could have produced those modifications.” And Gary Haynes, an archaeologist at the University of Nevada in Reno, notes that “the features of the broken bones … are also produced when heavy construction equipment crushes buried bones.” Author and site excavator Thomas Deméré, a paleontologist at the San Diego Natural History Museum, says the team carefully excavated 50 square meters beginning in 1992, and the bones described in the paper were “deeply buried. … There was no equipment damage to the heart of the site.” The lack of actual shaped stone tools, a “universal” at Old World sites, troubles archaeologist John Shea of the State University of New York in Stony Brook. Even the archaic humans that might have been present then, like Homo erectus or the mysterious Denisovans, left such flakes. “This evidence is well documented, but it’s not sufficient to close the case,” Shea says.


Herentalia nigra gen. et sp. nov. is described and compared to other mysticetes. It belongs to Cetotheriidae s.s. and represents one of the best-preserved cetotheriid skulls from the southern border of the North Sea. A comprehensive phylogenetic analysis revealed that it is closely related to Nannocetus and to a Japanese Herpetocetus, suggesting that it belongs to the subfamily Herpetocetinae. The phylogenetic analysis performed tests the recent hypothesis that Caperea marginata belongs to Cetotheriidae. However the present results confirm that the pygmy right whale cannot be considered a member of Cetotheriidae. The phylogenetic analysis was used as the basis for a cladistic palaeobiogeographical analysis of Cetotheriidae that revealed that the family originated in the Pacific basin during the Burdigalian and subsequently underwent a sequence of dispersal and vicariance events that allowed its members to enter other ocean basins. The evolution of Cetotheriidae diversity was punctuated by two distinct phases of species originations (one in the Burdigalian and the other in the Tortonian) that broadly correspond to a massive increase of food availability in the ocean trophic webs.http://zoobank.org/urn:lsid:zoobank.org:pub:DB1647B0-53E9-4014-B31A-F8B063923EB4 © 2014 © 2014 The Trustees of the Natural History Museum, London 2014. All Rights Reserved.

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