Friday, January 20, 2017
New evidence involving the ancient poop of some of the huge and astonishing creatures that once roamed Australia indicates the primary cause of their extinction around 45,000 years ago was likely a result of humans, not climate change.
Led by Monash University in Victoria, Australia and the University of Colorado Boulder, the team used information from a sediment core drilled in the Indian Ocean off the coast of southwest Australia to help reconstruct past climate and ecosystems on the continent. The core contains chronological layers of material blown and washed into the ocean, including dust, pollen, ash and spores from a fungus called Sporormiella that thrived on the dung of plant-eating mammals, said CU Boulder Professor Gifford Miller.
Miller, who participated in the study led by Sander van der Kaars of Monash University, said the sediment core allowed scientists to look back in time, in this case more than 150,000 years, spanning Earth's last full glacial cycle. Fungal spores from plant-eating mammal dung were abundant in the sediment core layers from 150,000 years ago to about 45,000 years ago, when they went into a nosedive, said Miller, a professor in the Department of Geological Sciences.
"The abundance of these spores is good evidence for a lot of large mammals on the southwestern Australian landscape up until about 45,000 years ago," he said. "Then, in a window of time lasting just a few thousand years, the megafauna population collapsed."
A paper on the subject was published online Jan. 20 in Nature Communications.
The Australian collection of megafauna some 50,000 years ago included 1,000-pound kangaroos, 2-ton wombats, 25-foot-long lizards, 400-pound flightless birds, 300-pound marsupial lions and Volkswagen-sized tortoises. More than 85 percent of Australia's mammals, birds and reptiles weighing over 100 pounds went extinct shortly after the arrival of the first humans, said Miller.
The ocean sediment core showed the southwest is one of the few regions on the Australian continent that had dense forests both 45,000 years ago and today, making it a hotbed for biodiversity, said Miller, also associate director of CU Boulder's Institute of Arctic and Alpine Research.
"It's a region with some of the earliest evidence of humans on the continent, and where we would expect a lot of animals to have lived," Miller said. "Because of the density of trees and shrubs, it could have been one of their last holdouts some 45,000 years ago. There is no evidence of significant climate change during the time of the megafauna extinction."
Scientists have been debating the causes of the Australian megafauna extinctions for decades. Some claim the animals could not have survived changes in climate, including a shift some 70,000 years ago when much of the southwestern Australia landscape went from a wooded eucalyptus tree environment to an arid, sparsely vegetated landscape.
Others have suggested the animals were hunted to extinction by Australia's earliest immigrants who had colonized most of the continent by 50,000 years ago, or a combination of overhunting and climate change, said Miller.
Miller said the extinction may have been caused by "imperceptible overkill." A 2006 study by Australian researchers indicates that even low-intensity hunting of Australian megafauna - like the killing of one juvenile mammal per person per decade - could have resulted in the extinction of a species in just a few hundred years.
"The results of this study are of significant interest across the archaeological and Earth science communities and to the general public who remain fascinated by the menagerie of now extinct giant animals that roamed the planet - and the cause of their extinction - as our own species began its persistent colonization of Earth," said van der Kaars.
In 2016 Miller used burned eggshells of the 400-pound bird, Genyornis, as the first direct evidence that humans actually preyed on the Australian megafauna.
Wednesday, January 18, 2017
The timing of the first entry of humans into North America across the Bering Strait has now been set back 10,000 years.
This has been demonstrated beyond a shadow of a doubt by Ariane Burke, a professor in Université de Montréal's Department of Anthropology, and her doctoral student Lauriane Bourgeon, with the contribution of Dr. Thomas Higham, Deputy Director of Oxford University's Radiocarbon Accelerator Unit.
Their findings were published in early January in the open-access journal PLoS One.
The earliest settlement date of North America, until now estimated at 14,000 years Before Present (BP) according to the earliest dated archaeological sites, is now estimated at 24,000 BP, at the height of the last ice age or Last Glacial Maximum.
The researchers made their discovery using artifacts from the Bluefish Caves, located on the banks of the Bluefish River in northern Yukon near the Alaska border. The site was excavated by archaeologist Jacques Cinq-Mars between 1977 and 1987. Based on radiocarbon dating of animal bones, the researcher made the bold hypothesis that human settlement in the region dated as far back as 30,000 BP.
In the absence of other sites of similar age, Cinq-Mars' hypothesis remained highly controversial in the scientific community. Moreover, there was no evidence that the presence of horse, mammoth, bison and caribou bones in the Bluefish Caves was due to human activity.
To set the record straight, Bourgeon examined the approximate 36,000 bone fragments culled from the site and preserved at the Canadian Museum of History in Gatineau -- an enormous undertaking that took her two years to complete. Comprehensive analysis of certain pieces at UdeM's Ecomorphology and Paleoanthropology Laboratory revealed undeniable traces of human activity in 15 bones. Around 20 other fragments also showed probable traces of the same type of activity.
"Series of straight, V-shaped lines on the surface of the bones were made by stone tools used to skin animals," said Burke. "These are indisputable cut-marks created by humans."
Bourgeon submitted the bones to further radiocarbon dating. The oldest fragment, a horse mandible showing the marks of a stone tool apparently used to remove the tongue, was radiocarbon-dated at 19,650 years, which is equivalent to between 23,000 and 24,000 cal BP (calibrated years Before Present).
"Our discovery confirms previous analyses and demonstrates that this is the earliest known site of human settlement in Canada," said Burke. It shows that Eastern Beringia was inhabited during the last ice age."
Beringia is a vast region stretching from the Mackenzie River in the Northwest Territories to the Lena River in Russia. According to Burke, studies in population genetics have shown that a group of a few thousand individuals lived in isolation from the rest of the world in Beringia 15,000 to 24,000 years ago.
"Our discovery confirms the 'Beringian standstill [or genetic isolation] hypothesis,'" she said, "Genetic isolation would have corresponded to geographical isolation. During the Last Glacial Maximum, Beringia was isolated from the rest of North America by glaciers and steppes too inhospitable for human occupation to the West. It was potentially a place of refuge."
The Beringians of Bluefish Caves were therefore among the ancestors of people who, at the end of the last ice age, colonized the entire continent along the coast to South America.
The results of Lauriane Bourgeon's doctoral research were published in the January 6 edition of PLoS One under the title "Earliest Human Presence in North America Dated to the Last Glacial Maximum: New Radiocarbon Dates from Bluefish Caves, Canada." The article is co-authored by Professor Burke and by Dr. Thomas Higham of Oxford University's Radiocarbon Accelerator Unit, in the U.K.
Maybe this Neanderthal was a rock hound?
An international group that includes a University of Kansas researcher has discovered a brownish piece of split limestone in a site in Croatia that suggests Neanderthals 130,000 years ago collected the rock that stands out among all other items in the cave.
"If we were walking and picked up this rock, we would have taken it home," said David Frayer, a professor emeritus of anthropology who was part of the study. "It is an interesting rock."
The finding is important, he said, because it adds to other recent evidence that Neanderthals were capable -- on their own -- of incorporating symbolic objects into their culture. The rock was collected more than 100 years ago from the Krapina Neanderthal site, which has items preserved in the Croatian Natural History Museum in Zagreb, where in recent years the research team has re-examined them.
The group's findings on the collected rock at Krapina were published recently in the French journal Comptes Rendus Palevol. Davorka Radovčić, curator at the Croatian Natural History Museum, was the study's lead author, and Frayer is the corresponding author.
The same research group in a widely recognized 2015 study published a PLOS ONE article about a set of eagle talons from the same Neanderthal site that included cut marks and were fashioned into a piece of jewelry.
"People have often defined Neanderthals as being devoid of any kind of aesthetic feelings, and yet we know that at this site they collected eagle talons and they collected this rock. At other sites, researchers have found they collected shells and used pigments on shells," Frayer said. "There's a little bit of evidence out there to suggest that they weren't the big, dumb creatures that everybody thinks they were."
Similar to the Neanderthal jewelry discovery at Krapina, Frayer credits Radovčić's keen eye in examining all items found at that the site, originally excavated between 1899-1905 and found to contain Neanderthal bones.
The cave at the Krapina site was sandstone, so the split limestone rock stuck out as not deriving from the cave, Frayer said. None of the more than 1,000 lithic items collected from Krapina resemble the rock, but the original archaeologists apparently did nothing more with the rock other than to collect it.
Frayer said the limestone rock -- which is roughly five inches long, four inches high and about a half-inch thick -- did not have any striking platforms or other areas of preparation on the rock's edge, so the research team assumed it was not broken apart.
"The fact that it wasn't modified, to us, it meant that it was brought there for a purpose other than being used as a tool," Frayer said.
There was a small triangular flake that fits with the rock, but the break appeared to be fresh and likely happened well after the specimen was deposited into the sediments of the Krapina site. Perhaps it occurred during transport or storage after the excavation around 1900, he said.
The look of the rock also caught the researchers' eye as many inclusions or black lines on it stood out from the brown limestone. Perhaps that is what made the Neanderthal want to collect it in the first place.
"It looked like it is important," Frayer said. "We went back through all the collected items to make sure there weren't other rocks like it. It just sat there for 100 years like most of the other stuff from the site. The original archaeologists had described stone tools, but didn't pay any attention to this one."
They suspect a Neanderthal collected the rock from a site a few kilometers north of the Krapina site where there were known outcrops of biopelmicritic grey limestone. Either the Neanderthal found it there or the Krapinica stream transported it closer to the site.
The discovery of the rock collection is likely minor compared with other discoveries, such as more modern humans 25,000 years ago making cave paintings in France. However, Frayer said it added to a body of evidence that Neanderthals were capable assigning symbolic significance to objects and went to the effort of collecting them.
The discovery could also provide more clues as to how modern humans developed these traits, he said.
"It adds to the number of other recent studies about Neanderthals doing things that are thought to be unique to modern Homo sapiens," Frayer said. "We contend they had a curiosity and symbolic-like capacities typical of modern humans."
Intact defensive structure, livestock pens provide insight into complexity of Iron Age copper production
The entrance complex with a two-room gatehouse flanked by animal pens and piles of dung.
Erez Ben-Yosef et al.
Some believe that the fabled mines of King Solomon were located among copper smelting camps in Israel's Timna Valley. The arid conditions at Timna have seen the astonishing preservation of 3,000-year-old organic materials, which have provided Tel Aviv University archaeologists with a unique window into the culture and practices of a sophisticated ancient society.
An advanced military fortification -- a well-defined gatehouse complex -- unearthed recently at Timna, including donkey stables, points to the community's highly-organized defense system and significant dependence on long-distance trade. The research was recently published in The Journal of Archaeological Science: Reports.
The fortification dates to the reigns of Kings David and Solomon in the 10th century BCE.
"While there is no explicit description of 'King Solomon's mines' in the Old Testament, there are references to military conflicts between Israel and the Edomites in the Arava Valley," says Dr. Erez Ben-Yosef of TAU's Institute of Archaeology and one of the leaders of the Timna research and excavation team, along with his colleagues Dr. Lidar Sapir-Hen and Dr. Dafna Langgut.
"According to the Bible, David traveled hundreds of miles outside of Jerusalem and engaged in military conflict in the desert -- striking down '18,000 Edomites in the Valley of Salt.' Now, having found evidence of defensive measures -- a sophisticated fortification -- we understand what must have been at stake for him in this remote region: copper."
"Copper was a rare product and very challenging to produce," Dr. Ben-Yosef continues. "Because copper -- like oil today, perhaps -- was the most coveted commodity, it landed at the very heart of military conflicts. The discovery of the fortification indicates a period of serious instability and military threats at that time in the region."
In the remarkably intact two-room fortification, located in one of the largest smelting camps in the Timna Valley, the researchers also found evidence of a complex long-distance trade system that probably included the northern Edomite plateau, the Mediterranean coastal plain and Judea. The complex featured pens for draught animals and other livestock. According to precise pollen, seed, and fauna analyses, they were fed with hay and grape pomace -- high-quality sustenance that must have been delivered from the Mediterranean region hundreds of miles away.
"The gatehouse fortification was apparently a prominent landmark," says Dr. Ben-Yosef. "It had a cultic or symbolic function in addition to its defensive and administrative roles. The gatehouse was built of sturdy stone to defend against invasion. We found animal bones and dung piles so intact, we could analyze the food the animals were fed with precision. The food suggests special treatment and care, in accordance with the key role of the donkeys in the copper production and in trade in a logistically challenging region."
Archaeology and the Old Testament
The site was discovered in 1934 by the American archaeologist Nelson Glueck. He called the copper smelting site "Slaves' Hill," because he believed it bore all the marks of an Iron Age slave camp, complete with fiery furnaces and a formidable stone barrier that seemed designed to prevent escape.
But in 2014 Dr. Ben-Yosef and colleagues debunked this theory, revealing that the diets and clothing of the smelters -- perfectly preserved by the desert conditions -- pointed instead to a hierarchical, sophisticated society.
"The historical accuracy of the Old Testament accounts is debated, but archaeology can no longer be used to contradict them," Dr. Ben-Yosef observes. "On the contrary, our new discoveries are in complete accordance with the description of military conflicts against a hierarchical and centralized society located south of the Dead Sea."
Dr. Ben-Yosef and his team plan to continue exploring the ancient societies that worked in these remote copper mines. "The unique preservation of organic materials in Timna, coupled with 21st century research methods including ancient DNA and residue analyses, bear the potential for additional significant discoveries in the future," says Dr. Ben-Yosef.
Thursday, January 12, 2017
A rare and intriguing discovery was revealed this weekend by hikers exploring a water cistern in the Judean Shephelah: on the walls of the cistern, which is hewn in Menorah and a Cross chalk bedrock, were incised ancient engravings of a seven-branched menorah and a cross.
Last weekend touring enthusiasts Mickey Barkal, Sefi Givoni and Ido Meroz, who are members of the Israel Caving Club, went out to visit hidden caves in the Judean Shephelah. According to hiker Ido Meroz, “We heard there are interesting caves in the region. We began to peer into them, and that’s how we came to this cave, which is extremely impressive with rock-carved niches and engravings on the wall. Just before we were about to return we suddenly noticed an engraving that at first glance seemed to be a menorah. When we realized this is an ancient depiction of a menorah, we became very excited. Its appearance was quite distinct. We left the cave and reported the discovery to the Israel Antiquities Authority”.
The menorah engraved on the wall of the cave has a base with three feet, and it evidently portrays the menorah that stood in the Temple during the Second Temple period. A cross was engraved near the menorah. Another engraving was found on the side of the cave which seems to resemble a type of key that is characteristic of antiquity, as well as other engravings that were noted, some of which have not yet been identified. Alongside the cistern is a columbarium with dozens of niches that were used to raise doves in antiquity. During the Second Temple period doves were used as part of the sacrificial rites in the Temple.
According to Sa'ar Ganor, the District Archaeologist of Ashkelon in the Israel Antiquities Authority, “There are buildings and hiding refuges from the time of the Bar Kokhba uprising (second century CE) at the site and buildings that date to the Byzantine period. It is rare to find a wall engraving of a menorah, and this exciting discovery, which was symbolically revealed during the Hanukkah holiday, substantiates the scientific research regarding the Jewish nature of the settlement during the Second Temple period”. Ganor added, “The menorah was probably etched in the cistern after the water installation was hewn in the bedrock – maybe by inhabitants of the Jewish settlement that was situated there during the Second Temple period and the time of Bar Kokhba – and the cross was etched later on during the Byzantine period, most likely in the fourth century CE.
The menorah is a distinctly Jewish symbol of the Second Temple period. To date, only two engravings of menorahs are known in the region of the Judean Shephelah: one on oil press at Bet Loya where the same style menorah is depicted, and the other in a burial complex in the vicinity of Bet Guvrin. Other menorahs are portrayed on clay lamps from Beit Natif.
In light of this interesting discovery, which adds another important tier to the archaeological information and knowledge about the region, the Israel Antiquities Authority will continue to study the site, whose exact location was not given in order to protect it and the safety of hikers.
The hikers who discovered the engravings will receive a good citizenship certificate and will be invited to participate in the coming archaeological surveys that the Israel Antiquities Authority will conduct in the Judean Shephelah.
Saturday, January 7, 2017
That conclusion challenges the previously held view that permanent human occupation of the Tibetan Plateau began no earlier than 5,200 years ago, after the advent of agriculture. The new finding is, however, consistent with research on the genetics of modern Tibetan Plateau people showing that they adapted genetically to the high-elevation environment beginning at least 8,000 years ago.
The research team includes Randy Haas, a postdoctoral research associate in the University of Wyoming's Department of Anthropology. The group was led by Michael Meyer of the University of Innsbruck in Austria and Mark Aldenderfer of the University of California-Merced. The multinational team includes scholars from institutions in Austria, Germany, New Zealand and the United States.
The researchers conducted an extensive analysis of human handprints and footprints found in 1998 in fossilized hot spring mud near the village of Chusang on Tibet's central plateau, at an elevation of 14,000 feet above sea level. Early analysis of the archaeological site indicated that the prints were made by people about 20,000 years ago, but the more thorough analysis dates them to at least 7,400 years ago, and possibly as early as 13,000 years ago. That still makes the Chusang site the oldest reliably dated archaeological site on the Tibetan Plateau.
While some have suggested that a human presence on the Tibetan Plateau at those early dates was only a result of short-term, seasonal movement from low-elevation base camps, the new research shows that it is much more likely that the handprints and footprints were made by permanent residents. Haas shows that the distance between lowland environments and the Chusang site would have required at least 230 miles of foot travel across the Himalayan arc -- a path far too long and treacherous for temporary use of the site, and far greater than what has been documented among most historic hunter-gatherers.
The early Tibetan Plateau settlers managed to survive at high elevation at least 7,400 years ago, before the development of an agricultural economy between 5,200-3,600 years ago.
"Although an agropastoral lifeway may have enabled substantial population growth after 5,000 years, it by no means was required for the early, likely permanent, occupation of the high central valleys of the Tibetan Plateau," the researchers wrote.
Haas says the research sheds new light on human colonization of high-elevation environments. For example, researchers have been puzzled by the striking differences in how Tibetans and Andean highlanders adapted physiologically to the rigors of life at high elevations.
"High-elevation environments (over 8,000 feet above sea level) were some of the last places in the world that humans colonized, and so they offer something of a natural laboratory for studying human adaptation," Haas says. "Research on high-elevation populations around the world tells us that there were multiple adaptive pathways involving various combinations of physiological, genetic and cultural responses. Our findings clarify that genetic and cultural responses on the Tibetan Plateau played out over considerably longer time spans than previously thought."
Wednesday, January 4, 2017
Deep in the caves of Goyet in Belgium researchers have found the grisly evidence that the Neanderthals did not just feast on horses or reindeer, but also on each other.
Human bones from a newborn, a child and four adults or teenagers who lived around 40,000 years ago show clear signs of cutting and of fractures to extract the marrow within, they say.
"It is irrefutable, cannibalism was practised here," says Belgian archaeologist Christian Casseyas as he looks inside a cave halfway up a valley in this site in the Ardennes forest.
The bones in Goyet date from when Neanderthals were nearing the end of their time on earth before being replaced by Homo sapiens, with whom they also interbred.
Once regarded as primitive cavemen driven to extinction by smarter modern humans, studies have found that Neanderthals were actually sophisticated beings who took care of the bodies of the deceased and held burial rituals.
But there is a growing body of proof that they also ate their dead....
The bones show traces of cutting, "to disarticulate and remove the flesh," said Christian Casseyas, who also leads tours for the public at the caves.
The Neanderthals "broke these bones in the same way that they broke those of the reindeer and horses found at the entrance of the cave, certainly to extract the marrow", he adds...
"Some of these bones have also been used to make tools to touch up the edges of flints to re-sharpen them," says Rougier.