Volcanoes Killed Off Neanderthals, Study Suggests
Modern humans escaped extinction due to their farther-flung populations?
for National Geographic News
Published September 22, 2010
Catastrophic volcanic eruptions in Europe may have culled Neanderthals to the point where they couldn't bounce back, according to a controversial new theory.
Modern humans, though, squeaked by, thanks to fallback populations in Africa and Asia, researchers say.
About 40,000 years ago in what we now call Italy and the Caucasus Mountains, which straddle Europe and Asia, several volcanoes erupted in quick succession, according to a new study to be published in the October issue of the journal Current Anthropology.
It's likely the eruptions reduced or wiped out local bands of Neanderthals and indirectly affected farther-flung populations, the team concluded after analyzing pollen and ash from the affected area.
The researchers examined sediments layer from around 40,000 years ago in Russia's Mezmaiskaya Cave and found that the more volcanic ash a layer had, the less plant pollen it contained.
"We tested all the layers for this volcanic ash signature. The most volcanic-ash-rich layer"—likely corresponding to the so-called Campanian Ignimbrite eruption, which occurred near Naples —"had no [tree] pollen and very little pollen from other types of plants," said study team member Naomi Cleghorn. "It's just a sterile layer."
The loss of plants would have led to a decline in plant-eating mammals, which in turn would have affected the Neanderthals, who hunted large mammals for food.
"This idea of an environmental cause for the Neanderthals' demise has been out in the literature. What we're trying to do is point out a specific mechanism," said Cleghorn, an anthropologist at the University of Texas, Arlington.
Other theories propose that modern humans played a vital role in the fall of the Neanderthals, either through competition, warfare, or interbreeding.
If the volcanoes theory is correct, the Neanderthals' end was much more tragic: dying slowly in a cold and desolate landscape bereft of food sources.
"It's hard to say what it would have been like to be the last few groups out there, seeing other groups less and less over the years," Cleghorn said.
The Neanderthals were a hardy species that lived through multiple ice ages and would have been familiar with volcanoes and other natural calamities. But the eruptions 40,000 years ago were unlike anything Neanderthals had faced before, Cleghorn and company say.
For one thing, all the volcanoes apparently erupted around the same time. And one of those blasts, the Campanian Ignimbrite, is thought to have been the most powerful eruption in Europe in the last 200,000 years.
"It's much easier to adapt to something that's happening over a couple of generations," Cleghorn said. "You can move around, you can find other places to live, and your population can rebound.
"This is not that kind of event," she said. "This is unique."
There may also have been small bands of Homo sapiens living in Europe at the time, Cleghorn said. They too would have been affected by the eruptions.
But modern humans likely avoided extinction because they had larger populations in Africa and Asia, she said, while most Neanderthals were in Europe around this time.
"With their small population groups, Neanderthals did not really have a great source population," Cleghorn said.
"They didn't really have the numbers and the density" to rebuild their populations after the eruptions.
The researchers acknowledge that there are gaps in the volcanoes theory. For instance, the time line needs to be better defined—did the volcanic eruptions occur in a period of months, years, or decades?
"At this point, it's impossible to pin down a reliable date" for the eruptions, Cleghorn said. "We can't say, This eruption happened 50 years before the next eruption. We just don't have that kind of resolution."
It's also unknown exactly how long it took the Neanderthals to die out—or how long after the eruptions modern humans began settling Europe in force, she said.
Anthropologist John Hoffecker, though, suggests that modern humans had already begun crowding out Neanderthals in Europe long before the eruptions in question.
Judging from discoveries of modern-human artifacts in former Neanderthal strongholds, Hoffecker said, "Neanderthals were clearly in trouble well before 40,000 years ago, because modern humans were occupying certain places, such as Italy, where Neanderthals had been present. So something clearly had gone wrong there."
Perhaps, he added, the volcanic eruptions just dealt the final blow.
"I'm not entirely convinced that's the case either," said Hoffecker, of the University of Colorado. "But at least that's a plausible scenario that's consistent with the chronology."
Study co-author Cleghorn counters that the modern human populations living in Europe 40,000 years ago were small and isolated, and only after the Neanderthals were gone did Homo sapiens populations explode.
"If modern humans were making any forays into European Neanderthal territory prior to this, they were doing it only on the very margins," Cleghorn said.
"What was keeping them from moving very quickly into the heart of Europe? We think Neanderthals were still holding their own and might have held out for much longer, if it hadn't been for the devastating impact of these eruptions."
Stone tools 'change migration story'
By Katie Alcock
Science reporter, BBC News, Birmingham
20 September 2010 Last updated at 00:25
A research team reports new findings of stone age tools that suggest humans came "out of Africa" by land earlier than has been thought.
Geneticists estimate that migration from Africa to South-East Asia and Australia took place as recently as 60,000 years ago.
But Dr Michael Petraglia, of Oxford University, and colleagues say stone artefacts found in the Arabian Peninsula and India point to an exodus starting about 70,000 to 80,000 years ago - and perhaps even earlier.
Petraglia, whose co-workers include Australian and Indian researchers, presented his ideas at the British Science Festival, which is hosted this year at Aston University.
"I believe that multiple populations came out of Africa in the period between 120,000 and 70,000 years ago," he said. "Our evidence is stone tools that we can date."
Most of the tools are from far inland - hundreds of kilometres from the coasts. This means it was more likely humans migrated by land than in boats, he said.
The tools are found in areas that are often very inhospitable now, but which at the time would have been much more conducive to migration.
"During the period we're talking about, the environments were actually very hospitable," he told BBC News. "So where there are deserts today, there used to be lakes and rivers, and there was an abundance of plants and animals."
The team found the stone tools - ranging from a couple of centimetres to nearly 10cm in size - in layers of sediment that they can date using sand and volcanic material found above and below the implements. The tools were mainly either spear heads or scrapers.
In particular, some tools were sandwiched in ash from the famous Toba eruption that geologists can date very accurately to 74,000 years ago.
Other species of early humans clearly left Africa before our species (Homo sapiens), but Dr Petraglia's team thinks that the tools it has found are the type made by modern humans - and not those of Neanderthals, for instance.
Previous research has leaned heavily on examining the genetics of different modern populations to find out how long ago they shared a common ancestor - their African common ancestor.
Professor Chris Stringer, of the Natural History Museum in London, said this genetic data showed humans left Africa around 60,000 years ago or even more recently.
He agreed that "these tools show that people were in these regions, but the genetic data show an exit from Africa of later than 60,000 years ago. The people in India could have died out."
Dr Petraglia, however, suggested that researching these migrations using population genetics might not lead to accurate results, because all of the genetic studies were based on today's people.
The absence of ancient DNA to make additional tests made this area of investigation much less reliable, he claimed.
Dr Petraglia's team now hopes to continue its excavations in the region. "We have literally hundreds of projects in Europe and a handful in the Arabian-South Asian belt," he said.
The Sex Toy for Cavewomen
SCIENTISTS in Sweden believe they have discovered the world's oldest sex-aid — and it's made from a stag antler.
The Stone Age phallus bears a startling resemblance to today's sex toys for women.
Made in 4,000 BC, the carving is six inches long and 0.8 inches in diameter.
Swedish archaeologist Martin Rundkvist said: "Without doubt anyone alive at the time of its making would have seen the penile similarities just as easily as we do today."
The sex toy was unearthed at a Mesolithic site in Motala, Sweden, which is rich with ancient artefacts from between 4000 to 6000 BC.
Bizarrely it was found among many other bone and stone fragments that appear to be related to harpooning.
Tom Carlsson's book is an explicit and emphatically postmodernist reconsideration of his 1999-2003 excavation at Motala-Strandvagen in Ostergotland in Sweden, a 90m long and 10-20m wide section of a late Mesolithic riverbank site of unknown extent. An earlier report was published in Swedish by the Riksantikvarieimbetet. The site was discovered and excavated--partly underwater--as a consequence of the construction of a new railway. The site is unique in central Sweden for its preservation of bone implements (c. 50 barbed point fragments) and refuse, allowing that part of the subsistence based on animal resources to be assessed. The excavation also produced 800 hammer stones, over 100 greenstone axes and 180 000 flint and quartz artefacts, two antler punches or pressure flakers and two pieces of decorated bone. Most important in the interpretation ('The home in the world--the world in the home') are two (incomplete) plans of structures: a larger oval one measuring 4 x 8.5m (plan) or 5 x 10m (text) and a smaller one, probably circular, of about 4m (plan) or 5m (text) in diameter. Both are indicated by dark shading on all the plans, although no depression or discolouration is mentioned in the text. A warning is issued to those who are sceptical about these houses: they will have to put up with 'the Mesolithic house syndrome'. Thirty [sup.14]C dates are spread between c. 5900 and 4500 cal BC, but the main occupation is considered to date to 5500-5000 BC. Most interesting and really unique are two concentrations of fist-sized pebbles in the muddy bank zone, interpreted as platforms for leister fishing: close to these stones at least 17 broken tips of bone barbed points (Figure 17) were recovered 'in vertical position deep down in the bottom of the river'.
Parting the waters: Computer modeling applies physics to Red Sea escape route
September 21, 2010
The biblical account of the parting of the Red Sea has inspired and mystified people for millennia. A new computer modeling study by researchers at the National Center for Atmospheric Research (NCAR) and the University of Colorado at Boulder (CU) shows how the movement of wind as described in the book of Exodus could have parted the waters.
The computer simulations show that a strong east wind, blowing overnight, could have pushed water back at a bend where an ancient river is believed to have merged with a coastal lagoon along the Mediterranean Sea. With the water pushed back into both waterways, a land bridge would have opened at the bend, enabling people to walk across exposed mud flats to safety. As soon as the wind died down, the waters would have rushed back in.
The study is intended to present a possible scenario of events that are said to have taken place more than 3,000 years ago, although experts are uncertain whether they actually occurred. The research was based on a reconstruction of the likely locations and depths of Nile delta waterways, which have shifted considerably over time.
“The simulations match fairly closely with the account in Exodus,” says Carl Drews of NCAR, the lead author. “The parting of the waters can be understood through fluid dynamics. The wind moves the water in a way that’s in accordance with physical laws, creating a safe passage with water on two sides and then abruptly allowing the water to rush back in.”
The study is part of a larger research project by Drews into the impacts of winds on water depths, including the extent to which Pacific Ocean typhoons can drive storm surges. By pinpointing a possible site south of the Mediterranean Sea for the crossing, the study also could be of benefit to experts seeking to research whether such an event ever took place. Archeologists and Egyptologists have found little direct evidence to substantiate many of the events described in Exodus.
The work, published in the online journal, PLoS ONE, arose out of Drews’ master’s thesis in atmospheric and oceanic sciences at CU. The computing time and other resources were supported by the National Science Foundation.
The Exodus account describes Moses and the fleeing Israelites trapped between the Pharaoh's advancing chariots and a body of water that has been variously translated as the Red Sea or the Sea of Reeds. In a divine miracle, the account continues, a mighty east wind blows all night, splitting the waters and leaving a passage of dry land with walls of water on both sides. The Israelites are able to flee to the other shore. But when the Pharaoh's army attempts to pursue them in the morning, the waters rush back and drown the soldiers.
Scientists from time to time have tried to study whether the parting of the waters, one of the famous miracles in the Bible, can also be understood through natural processes. Some have speculated about a tsunami, which would have caused waters to retreat and advance rapidly. But such an event would not have caused the gradual overnight divide of the waters as described in the Bible, nor would it necessarily have been associated with winds.
Other researchers have focused on a phenomenon known as “wind setdown,” in which a particularly strong and persistent wind can lower water levels in one area while piling up water downwind. Wind setdowns, which are the opposite of storm surges, have been widely documented, including an event in the Nile delta in the 19th century when a powerful wind pushed away about five feet of water and exposed dry land.
A previous computer modeling study into the Red Sea crossing by a pair of Russian researchers, Naum Voltzinger and Alexei Androsov, found that winds blowing from the northwest at minimal hurricane force (74 miles per hour) could, in theory, have exposed an underwater reef near the modern-day Suez Canal. This would have enabled people to walk across. The Russian study built on earlier work by oceanographers Doron Nof of Florida State University and Nathan Paldor of Hebrew University of Jerusalem that looked at the possible role of wind setdown.
The new study, by Drews and CU oceanographer Weiqing Han, found that a reef would have had to be entirely flat for the water to drain off in 12 hours. A more realistic reef with lower and deeper sections would have retained channels that would have been difficult to wade through. In addition, Drews and Han were skeptical that refugees could have crossed during nearly hurricane-force winds.
Reconstructing ancient topography
Studying maps of the ancient topography of the Nile delta, the researchers found an alternative site for the crossing about 75 miles north of the Suez reef and just south of the Mediterranean Sea. Although there are uncertainties about the waterways of the time, some oceanographers believe that an ancient branch of the Nile River flowed into a coastal lagoon then known as the Lake of Tanis. The two waterways would have come together to form a U-shaped curve.
An extensive analysis of archeological records, satellite measurements, and current-day maps enabled the research team to estimate the water flow and depth that may have existed 3,000 years ago. Drews and Han then used a specialized ocean computer model to simulate the impact of an overnight wind at that site.
They found that a wind of 63 miles an hour, lasting for 12 hours, would have pushed back waters estimated to be six feet deep. This would have exposed mud flats for four hours, creating a dry passage about 2 to 2.5 miles long and 3 miles wide. The water would be pushed back into both the lake and the channel of the river, creating barriers of water on both sides of newly exposed mud flats.
As soon as the winds stopped, the waters would come rushing back, much like a tidal bore. Anyone still on the mud flats would be at risk of drowning.
The set of 14 computer model simulations also showed that dry land could have been exposed in two nearby sites during a windstorm from the east. However, those sites contained only a single body of water and the wind would have pushed the water to one side rather than creating a dry passage through two areas of water.
“People have always been fascinated by this Exodus story, wondering if it comes from historical facts,” Drews says. “What this study shows is that the description of the waters parting indeed has a basis in physical laws."
About the article Title: Dynamics of Wind Setdown at Suez and the Eastern Nile Delta
Authors: Carl Drews and Weiqing Han
Publication: PLos ONE; the article may be read online or downloaded from: http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0012481
Ancient remains discovered in Yorkshire
21 September 2010
A group of archaeology enthusiasts discovered a cup-and-ring stone in Steeton (West Yorkshire, England). According to a short report sent by Mr Paul Bennett, on the stone there are at least 19 cup-markings and a series of serpentine, curved lines running between and towards the cup-markings. Although some of the cups give an impression of being natural, others have the authentic-looking ring to them, with at least one of them possessing a near-complete ring encircling it.
Mr Bennett believes the carving has a similar feel in design, although graphically different, to that of the Wondjina Stone at Rivock Edge, on the other side of the Aire Valley a couple of miles east of the site - though this newly found carving is in a better state of preservation. The discoverers gave the newly discovered stone the imaginative title of the Dragon Stone.
The same group of people recently discovered more ancient remains on the North Yorkshire moors. When looking at a small, overgrown circle known as Dumpit Hill, one of the team of archaeolgy enthusiasts came across the lost stone circle of Dumpit Hill B, first reported by Arthur Raistrick in 1963. Thankfully much of the heathland had been burnt away, which enabled the group to uncover a near-complete ring of eight stones insted of the three originally reported by Mr Raistrick 47 years ago.
Nearby, Michala Douglas located a large prehistoric enclosure site. Structurally similar to the enclosure walling at Horse Close and Rough Haw, either side of Skipton, a few miles to the south, here there are about 100 yards of walling seeming to enclose the eastern side of the small hilltop, but running into the heather on its southern edge and the moorland track on its northern side, where it disappears again. At the northwestern point in the enclosure walling, a very distinct long stone about 4 feet high leans at an angle in the ling.
The group contacted Robert White of North Yorkshire's Historic Environment Office asking whether the site had previously been recorded, but he reported they have no record of sites at this spot. Mr White said he's planning a visit to the place soon to survey the site.
Edited from The Northern Antiquarian (13 and 18 August 2010, 4 september 2010) and from messages sent by Paul Bennett
Animal burials at Carshalton
Posted Thu, 09/23/2010 - 12:44
A series of 2,000 year old animal burials have been found at Carshalton, London Borough of Sutton.
The burials, which were placed in pits, were discovered in an excavation being done before Stanley Park High School moves from its current location to a new site on the former Queen Mary’s Hospital at Orchard Hill. The pits belonged to a farm that was lived in before the Roman conquest in AD 43 and which continued to be occupied for a few generations afterwards. At this time people lived in round houses which had conical thatched roofs.
The burial of animals in pits is well known in Iron Age Britain and is part of a tradition of making offerings to the gods of the underworld. The pits were probably originally dug to store grain through the winter before sown in the spring. When the pits passed out of use the farmers buried valuable things in the pits before filling them in. At Carshalton the animals, which were probably sacrificed, include horses.
As well as the animal burials, Bronze Age remains have also been found. Small gullies, perhaps field boundaries, and what may be droveways for cattle may be associated with the nearby Queen Mary’s fort. The circular fort dates to the Late Bronze Age and 2,800 years ago it was one of the most important sites in the south. It was discovered when the hospital, which was a children’s hospital, was built at the beginning of the 20th century.
The excavation is the latest in a series to be undertaken in recent years. As the hospital was gradually decommissioned over the last decade, archaeological works took place before redevelopment. Archaeologists also made thorough surveys of the hospital, carefully recording the buildings before they were demolished.
Some of our previous work close to this site has been published in the article "Excavations within and close to the Late Bronze Age Enclosure at the former Queen Mary’s Hospital Carshalton" by Jan Groves and Julie Lovell in London Archaeologist (Volume 10 No. 1 Summer 2002 pp 13-19), and is available online from the Archaeology Data Service.
A technical report for an archaeological evaluation consisting of fifteen trial trenches conducted on the site of the former hospital in August 2008, is also available.
Roman circus uncovered at Outlane
Sep 23 2010 Huddersfield Daily Examiner
FORGET the Galpharm Stadium!
Local archaeologists have discovered Huddersfield’s long-lost circus or sporting arena, built by the Romans in the village of Outlane nearly 2,000 years ago.
And they believe crowds of up to 2,000 would pack into the amphitheatre to watch horsemanship displays by the Roman cavalry.
The soldiers were based at the Slack Roman fort, built to protect the military road from Chester to York.
The fort was fully active from about AD 80 to AD 140 and housed a cavalry unit that could spring into action to quell any uprising by the local Brigantian tribe and was active in the Roman conquest of the north.
Now excited archaeologists have uncovered what they believe was the amphitheatre used by the troops to exercise and to show off their horsemanship skills.
Granville Clay, project co-ordinator for the Huddersfield and District Archaeological Society, said: “It is a very exciting find.
“We had studied an old map dating from 1854 which had a circle marked on it and the words ‘Circus here’.
“It means that the Slack fort was probably far more important in Roman history than people have previously believed.
“Roman forts had paved areas outside the walls where soldiers could exercise and train for battle.
“Some cavalry forts had an enclosed circus area where horses could be trained and sometimes raced for the entertainment of the garrison and this is what we have found.
“Horse racing and chariot racing was common throughout the Roman Empire and the circus recently discovered at Colchester is the largest so far found in Britain”
The one found at Outlane is about 80 metres in diameter but the exact shape is not known because New Hey Road cuts right through the middle of it and much of it has been built over.
A raised banking surrounds what is thought to have been a stone base.
The section excavated near Slack Lane has a hard compacted area of stone and rubble which would form the floor of the arena with a curving bank of stone and earth on the outside.
Mr Clay said: “People have heard of the Circus Maximus in Rome, but many of the forts had their own circus, or amphitheatre.
“This one is quite big and I would estimate up to 2,000 people could be there to watch the horse shows.
“People have previously thought the fort was abandoned when the garrison left, but we now have evidence that it was in use for much, much longer, with people living there to look after travellers using the Roman road through Slack and to maintain the road itself.”
The Society is currently excavating at Slack to discover more about the water supply to the Roman fort and any evidence of how long the Roman road was in use after the fort was no longer used by the army.
The public can view the excavation tomorrow and Saturday between 10am and 4pm.
Long-Sought Viking Settlement Found
by Seán Duke on 22 September 2010, 10:51 AM
The Vikings, the famed Scandinavian warriors, started raiding Ireland in 795 and plundered it for decades, before establishing two Irish outposts, according to the Annals of Ulster, a 15th century account of medieval Ireland. One outpost, Dúbh Linn, became Dublin, the other, Linn Duchaill, was lost in time. Perhaps until now. A team of archaeologists announced on Friday that it has found the lost Viking settlement near the village of Annagassan, 70 kilometers north of Dublin. "We are unbelievably delighted," said archaeologist and team leader, Mark Clinton, an independent archaeological consultant.
The Annagassan locals have long believed they lived near an ancient Viking town or fort. The stories of Viking raids were told to local children by schoolteachers, and there were also occasional finds that underscored this story. For example, a few years ago, a set of handcuffs once used to shackle Viking slaves was found by a farmer ploughing land. The modern search for Linn Duchaill began 5 years ago when a local filmmaker named Ruth Cassidy, a member of the Annagassan and District Historical Society, enlisted the help of Clinton, a family friend, to find the lost Viking town. They searched through 2005, 2006, and 2007 and were on the point of despair when they came across a flat area—ideal for lifting boats out of the water for shipbuilding and repairs—a couple of kilometers up the River Glyde. They managed to secure funding to pay for a geophysicist, John Nicholls, to survey the site. Nicholls found a series of defensive ditches about 4 meters deep, running in lines. The pattern of ditches does not seem compatible with the typical Irish structure of the period, a ring fort, and no evidence of a Norman settlement, such as moat or castle remains, was found. That left just one other option: Vikings.
Despite this evidence, the researchers struggled to secure funding for excavation work. But the local Louth County Museum eventually offered funds to excavate at three locations. The team found 200 objects in 3 weeks, convincing them that they had found a major Viking shipbuilding town. There is evidence of impressive engineering, with an artificial island constructed out of the landscape to offer protection from attacks by the indigenous Irish. There is evidence of carpentry, smelting, and ship repair, with ship rivets dotted around the site. These features alone would make the site significant as few Viking longphorts—or shipbuilding towns—have been excavated. The team also found hacked coins, which Clinton says were a typical "calling card" of the Vikings, but there is also a total absence of pottery—the Vikings used wooden bowls. There are "high status" early Christian objects, too, probably stolen from the Irish.
Other Viking experts are cautiously optimistic that the long-lost Viking outpost has been found but emphasize the settlement needs to be solidly dated before the case is closed. "If the settlement found can be identified as Linn Duchaill, its value for linking archaeology to the written sources is very important," says Peter Pentz, an archaeologist at the National Museum of Denmark in Copenhagen. "In addition, it appears that the site is almost untouched by later activity, unlike those of Dublin—some longphorts developed into urban settlements—and thus it might provide important knowledge of this particular type of settlement."
"It's really, really exciting," adds Christina Lee of the University of Nottingham in the United Kingdom, an expert in Viking studies of Ireland and Britain. "I'm looking forward to hearing about the finds and the dating of the finds. It's a really important step in thinking about the westward expansion of the Vikings, and the importance that Ireland had for the Viking world is something that hasn't been recognized. Ireland in the Viking age is of strategic importance."
One lingering question is why Linn Duchaill was abandoned while Dublin thrived. One theory is that because Dublin has better 24-hour access to the sea, it meant that the Vikings there could take to their ships and head out when they were under attack. At Linn Duchaill, tidal fluctuations would cut off access for several hours a day.