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Stones Forum >> Neanderthals
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coldrum
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|  Posted 25-08-2010 at 11:00
'Callao Man' Could Redraw Filipino History
A foot bone from a human that lived 67,000 years ago suggests settlers first arrived earlier than once thought.
THE GIST
* Archaeologists have discovered a human foot bone that dates back 67,000 years.
* The finding pushes back the timeline of human settlement in the Philippines.
* The discovery also suggests that raft- or boat-building crafts would have been around at that time.
Archaeologists have been exploring the Callao caves system since the 1970s. Click to enlarge this image.
Getty Images
Archaeologists have found a foot bone that could prove the Philippines was first settled by humans 67,000 years ago, thousands of years earlier than previously thought, the National Museum said Tuesday.
The bone, found in an extensive cave network, predates the 47,000-year-old Tabon Man that is previously known as the first human to have lived in the country, said Taj Vitales, a researcher with the museum's archaeology section.
"This would make it the oldest human remains ever found in the Philippines," Vitales told AFP.
Archaeologists from the University of the Philippines and the National Museum dug up the third metatarsal bone of the right foot in 2007 in the Callao caves near Penablanca, about 335 kilometers (210 miles) north of Manila.
Their report on "Callao Man" was released in the latest edition of the Journal of Human Evolution after tests in France established the fossil's age, said professor Armand Mijares, the expedition leader.
"It broke the barriers," Mijares said, explaining that previous evidence put the first human settlements in the Philippines and nearby islands around Tabon Man. "It pushed that back to nearly 70,000 years."
Cut marks on bones of deer and wild boar found around it suggest Callao Man could have hunted and was skilled with tools, although no cutting or other implements were found during the dig, according to Mijares.
"This individual was small-bodied. It's difficult to say whether he was male or female," he said.
Mijares stressed the finding that Callao Man belongs to Homo sapiens was still only provisional. Some of the bone's features were similar to Homo habilis and Homo floresiensis -- which are distinct species from humans.
Existing evidence suggests that Homo sapiens, modern man, first appeared in Africa about 200,000 years ago.
Homo habilis is considered a predecessor to Homo sapiens while Homo floresiensis is thought to be a short, human-like species that once existed on an Indonesian island in the Late Pleistocene stage.
To determine whether Callao Man was human, Mijares said his team planned to secure permits to pursue further excavations in the Callao caves and hopefully find other parts of the skeleton, tools, or fossils of other potential humans.
Mijares said Callao Man also shared some features of today's Aetas, a short, curly-haired and dark-skinned people who are thought to be directly descended from the first inhabitants of the Philippines.
The discovery also suggests that raft- or boat-building crafts would have been around at that time.
"The hypothesis is that the Philippines, which is surrounded by bodies of water, was first reached by humans aboard rafts," Vitales said.
But he said there was no consensus on whether the first settlers came from mainland Asia, neighboring Southeast Asian islands or elsewhere.
Archaeologists have been exploring the Callao caves system since the 1970s. "Generally caves are used as habitations and burial sites," Vitales said.
Tabon Man, the fossilized fragments of a skull and jawbone from three individuals, was discovered along with stone flake tools by a National Museum team in a cave on the western Philippine island of Palawan in May 1962.
http://news.discovery.com/archaeology/callao-man-philippines.html
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coldrum
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| Posted 25-08-2010 at 11:01
'Mitochondrial Eve': Mother of All Humans Lived 200,000 Years Ago
The most robust statistical examination to date of our species' genetic links to "mitochondrial Eve" -- the maternal ancestor of all living humans -- confirms that she lived about 200,000 years ago. The Rice University study was based on a side-by-side comparison of 10 human genetic models that each aim to determine when Eve lived using a very different set of assumptions about the way humans migrated, expanded and spread across Earth.
The research is available online in the journal Theoretical Population Biology.
"Our findings underscore the importance of taking into account the random nature of population processes like growth and extinction," said study co-author Marek Kimmel, professor of statistics at Rice. "Classical, deterministic models, including several that have previously been applied to the dating of mitochondrial Eve, do not fully account for these random processes."
The quest to date mitochondrial Eve (mtEve) is an example of the way scientists probe the genetic past to learn more about mutation, selection and other genetic processes that play key roles in disease.
"This is why we are interested in patterns of genetic variability in general," Kimmel said. "They are very important for medicine."
For example, the way scientists attempt to date mtEve relies on modern genetic techniques. Genetic profiles of random blood donors are compared, and based upon the likenesses and differences between particular genes, scientists can assign a number that describes the degree to which any two donors are related to one another.
Using mitochondrial genomes to gauge relatedness is a way for geneticists to simplify the task of finding common ancestors that lived long ago. That is because the entire human genome contains more than 20,000 genes, and comparing the differences among so many genes for distant relatives is problematic, even with today's largest and fastest supercomputers.
But mitochondria -- the tiny organelles that serve as energy factories inside all human cells -- have their own genome. Besides containing 37 genes that rarely change, they contain a "hypervariable" region, which changes fast enough to provide a molecular clock calibrated to times comparable to the age of modern humanity. Because each person's mitochondrial genome is inherited from his or her mother, all mitochondrial lineages are maternal.
To infer mtEve's age, scientists must convert the measures of relatedness between random blood donors into a measure of time.
"You have to translate the differences between gene sequences into how they evolved in time," said co-author Krzysztof Cyran, vice head of the Institute of Informatics at Silesian University of Technology in Gliwice, Poland. "And how they evolved in time depends upon the model of evolution that you use. So, for instance, what is the rate of genetic mutation, and is that rate of change uniform in time? And what about the process of random loss of genetic variants, which we call genetic drift?"
Within each model, the answers to these questions take the form of coefficients -- numeric constants that are plugged into the equation that returns the answer for when mtEve lived.
Each model has its own assumptions, and each assumption has mathematical implications. To further complicate matters, some of the assumptions are not valid for human populations. For example, some models assume that population size never changes. That is not true for humans, whose population has grown exponentially for at least several thousand generations. Other models assume perfect mixing of genes, meaning that any two humans anywhere in the world have an equal chance of producing offspring.
Cyran said human genetic models have become more complex over the past couple of decades as theorists have tried to correct for invalid assumptions. But some of the corrections -- like adding branching processes that attempt to capture the dynamics of population growth in early human migrations -- are extremely complex. Which raises the question of whether less complex models might do equally well in capturing what's occurring.
"We wanted to see how sensitive the estimates were to the assumptions of the models," Kimmel said. "We found that all of the models that accounted for random population size -- such as different branching processes -- gave similar estimates. This is reassuring, because it shows that refining the assumptions of the model, beyond a certain point, may not be that important in the big picture."
The research was supported by grants from the Polish Ministry of Science and Higher Education and the Cancer Prevention and Research Institute of Texas. It has resulted from a standing collaboration between Rice University and Silesian University of Technology.
http://www.sciencedaily.com/releases/2010/08/100817122405.htm
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coldrum
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| Posted 25-08-2010 at 11:01
Cannibal cavemen of Spain uncovered
More evidence that The Flintstones didn't tell us the whole story about cavemen. Our prehuman ancestors cannibalized one another for the "nutritional value" starting about a million years ago, finds an analysis of bones left in a Spanish cave.
In the journal Current Anthropology, a team led by archaeologist Eudald Carbonell of Spain's University of Rovira and Virgili, report fossil evidence of continuous cannibalism - cut marks and butchering remains - as a way of life among the Homo antecessor inhabitants of the Atapuerca Mountains archeological site.
From a sample of some 1,039 bones that included mammoths, buffalo, cats and other butchered species found in the cave level deposited more than 800,000 years ago, there also emerged 159 bones from 11 H. antecessor individuals, they report:
"Cut marks (slicing, chop, and scraping marks) on the cranial segment are abundant on the base of the temporal bones, face, and zygomatic bones: segments with a large amount of muscular attachments and ligaments. Cut marks found on the face indicate skinning and defleshing activities. Cranial fragments also display abundant evidence of breakage (percussion pits and adhered flakes) mainly located on the lower part of the cranium. The majority of zygomatic bones are broken in a similar manner to those documented in Native American cannibalized remains and Neolithic (post 9500 BC) individuals," says the study.
Modern humans did not arrive in Spain until around 30,000 years ago. An "archaic" human species, H. Antecessor possessed a brain about two-thirds the size of modern humans. They are thought to be ancestral to both modern humans and our Neanderthal cousins, who disappeared from the fossil record about the time of the first modern-looking humans in Europe.
The cannibalized bones from the Spanish site, tossed in with the bones of animals butchered for food, suggest that cannibalism was just another dietary option for these early cavemen, one with neither symbolic meaning or pursued solely as a survival strategy during famine.
Instead, the study authors suggest they "added cannibalism to their set of survival strategies as a way of competing with other human groups for available resources. This practice, accepted and included in their social system, is the oldest example of cultural cannibalism known to date. "
http://content.usatoday.com/communities/sciencefair/post/2010/08/cannibal-cavemen-spain-nutrition/1
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John_Seaford
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| Posted 25-08-2010 at 17:16
I watched this show on our USA public TV called the "Human Spark" . The host, Alan Alda, went on and on about how wonderfull humans are because we have the Human Spark and how we developed new technologies and culture and blah, blah blah. He keep putting down Neanderthals because they stayed the same.
I must say I am fond of Neanderthals. They were around for 200 thousand years so they most have got something right. In the end they may have more successfull then us because we are on the path of creating a wholesale planetary meltdown. All these great new things our spark gave us may overwelm the earth's environment and destroy life as we know it. This will make us the least sucessfull species yet.
The Neanderthals were able to move around and adapt some. Their skulls and sites did change over time. But for the most part their way of life worked. They lived with nature. But what I really like about them is that they cared for one another and burried each other with care.
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coldrum
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| Posted 31-08-2010 at 11:26
Israel researchers find ancient disposable cutlery
Israeli archaeologists believe thousands of ancient shards of flint found scattered around a fire pit in a cave near Tel Aviv might be the world's oldest known disposable knives.
Dating to the Stone Age, the tiny knives are believed to be at least 200,000 years old. A Tel Aviv University excavation team found the tools around a fireplace littered with charred animal bones.
Archaeologist Ran Barkai said he believes Stone Age hunter-gatherers used the rough, round-shaped cutlery — ranging from the size of human teeth to guitar picks — for slicing through cooked meat because they were found next to the animal bones. The bones were used to determine the age of the knives.
The number of knives found, coupled with the fact that they had no signs of sharpening, indicates they were disposable because they would have dulled after several uses, he said.
The knives were made from recycled material — parts of larger knives and tools designed for other uses such as butchering animals and scraping hides, he said.
"They are made in a special way. On the one hand, they are very efficient and on the other, very simple," Barkai said.
Working with replicas made from other stones found in the cave, an expert determined that the wear and tear resulting from cutting soft tissues, like meat, matched marks found on the ancient knives.
Barkai said that while people have been cutting meat for the last 2 million years, these knives stood out because of their small size and the fact that they were disposable and made from recycled materials.
"Such tiny meat-eating knives were never discovered before," he said.
Yorke Rowan, an archaeologist from the University of Chicago who was not involved in the dig, said the discovery still leaves a number of questions unanswered, such as why the tools are so small and why the makers would have bothered to recycle materials when they had access to a large supply of flint stones.
But the finding is significant, he said, because it shows that materials "that have traditionally been treated as waste might actually be tools."
Barkai published the findings in the September issue of Antiquity, a quarterly journal.
http://www.google.com/hostednews/ap/article/ALeqM5hN7Ey0ODIgE7N6t0iBgvwqMhbIdgD9HTRSJG0
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coldrum
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| Posted 02-09-2010 at 19:04
Archaelogical dig at Orce, Granada, reveals riches
The site is being considered to be one of the best in Western Europe
The importance of a new archaeological dig at Fuente Nueva 3 and Barranco León, in Orce, Granada, is becoming clear.
In the first two days of the new dig, remains of elephants, rhinoceros, hippopotamus and deer have been found, and evidence that these animals were eaten by humans.
The news was given by the Project Director, Robert Sala. He described the finds at Orce as ‘the richest and the best in Western Europe’ as the site could show human existence at a particular time. He said such human evidence was greater at Orce than at Sima del Elefante, at Atapuerca, Burgos, and that made the site more important, provided the expected human fossils are found, dating from 1.3 million years ago.
The excavations at the site will continue until September 22. 45 people, including archaeologists, geologists and palaeontologists are working together to investigating human evolution.
Read more: http://www.typicallyspanish.com/news/publish/article_27041.shtml#ixzz0wT1j46fV
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bat400
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| Posted 28-09-2010 at 04:47
Neanderthals were able to 'develop their own tools'
Submitted by coldrum .
Neanderthals were keen on innovation and technology and developed tools all on their own, scientists say. A new study challenges the view that our close relatives could advance only through contact with Homo sapiens. The team says climate change was partly responsible for forcing Neanderthals to innovate in order to survive.
The research is set to appear in the Journal of Archaeological Method and Theory in December.
"Basically, I am rehabilitating Neanderthals," said Julien Riel-Salvatore, assistant professor of anthropology at the University of Colorado in Denver, who led the seven-year study.
"They were far more resourceful than we have given them credit for."
Neanderthals were first discovered in Germany's Neander Valley in 1856. It is believed that they lived in Europe and parts of Asia. Close examination of the found fossils shows that they shared 99.5-99.9% of modern humans' DNA, which makes them our closest relatives. They had short, muscular bodies, large brains, prominent facial features and barrel chests. Neanderthals split from our evolutionary line some 500,000 years ago, and disappeared off the face of the Earth about 30,000 years ago.
Since the first discovery, anthropologists have been trying to crack the mystery of the vanished culture, also debating whether or not Neanderthals were evolving on their own or through contact with Homo sapiens.
During the research, Dr Riel-Salvatore and his colleagues examined Neanderthal sites across Italy.
About 42,000 years ago, Homo sapiens and Neanderthals were already living in the northern and central parts of the area.
At that time, an entirely new group appeared in the south. The researchers believe that the southerners were also Neanderthals, of a culture named Uluzzian.
Dr Riel-Salvatore's team was astonished to find quite a few innovations throughout the area, even though the Uluzzians were isolated from Homo sapiens. They discovered projectile points, ochre, bone tools, ornaments and possible evidence of fishing and small game hunting.
"My conclusion is that if the Uluzzian is a Neanderthal culture, it suggests that contacts with modern humans are not necessary to explain the origin of this new behaviour.
"This stands in contrast to the ideas of the past 50 years that Neanderthals had to be acculturated to [modern] humans to come up with this technology.
"When we show Neanderthals could innovate on their own, it casts them in a new light.
"It 'humanises' them, if you will."
The researchers believe that one reason that forced Neanderthals to innovate was a shift in climate. When the area where they were living started to become increasingly open and arid, they had no choice but to adapt - or die out.
"The fact that Neanderthals could adapt to new conditions and innovate shows they are culturally similar to us," said Dr Riel-Salvatore. He added that they were also similar biologically, and should be considered a subspecies of human rather than a different species.
Neanderthals were keen on innovation and technology and developed tools all on their own, scientists say. A new study challenges the view that our close relatives could advance only through contact with Homo sapiens.
Source : http://www.bbc.co.uk/news/science-environment-11408298
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bat400
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| Posted 28-09-2010 at 04:50
Volcanoes Killed Off Neanderthals, Study Suggests
Submitted by coldrum --
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 (map)—"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.
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."
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."
For more, see http://news.nationalgeographic.com/news/2010/01/100922-volcanoes-eruptions-neanderthals-science-volcanic-humans/
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bat400
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| Posted 08-10-2010 at 04:41
The Prehistory of Compassion: Neanderthals Cared Too
Submitted by coldrum --
New research by archaeologists at the University of York suggests that it is beyond reasonable doubt Neanderthals – often misrepresented as furry, primitive caveman hobbling about – had a deep seated sense of compassion.
Dr Penny Spikins, Andy Needham and Holly Rutherford from the university’s Department of Archaeology examined the archaeological record in search for evidence for compassionate acts in early humans. These illustrate the way emotions began to emerge in our ancestors six million years ago, which developed into the idea of 'compassion' we know today.
Nowadays, 'compassion' is considered a great virtue by numerous philosophies and all the major religious traditions. But when did start to grow a desire to soother others' distress? In the study 'From hominity to humanity: Compassion from the earliest archaic to modern humans', the researchers took on the ‘unique challenge’ of charting key stages in the evolution early human's emotional motivation to help others. They propose a four stage model for the development of human compassion:
Compassion is perhaps the most fundamental human emotion. It binds us together and can inspire us but it is also fragile and elusive
Stage 1 - It begins six million years ago when the common ancestor of humans and chimpanzees experienced the first awakenings of an empathy for others and motivation to ‘help’ them, perhaps with a gesture of comfort or moving a branch to allow them to pass.
Stage 2 - The second stage from 1.8 million years ago sees compassion in Homo erectus beginning to be regulated as an emotion integrated with rational thought. Care of sick individuals represented an extensive compassionate investment while the emergence of special treatment of the dead suggested grief at the loss of a loved one and a desire to soothe others feelings.
Stage 3 - In Europe between around 500,000 and 40,000 years ago, early humans such as Homo heidelbergensis and Neanderthals developed deep-seated commitments to the welfare of others illustrated by a long adolescence and a dependence on hunting together.
There is evidence of the routine care of the injured or infirm over extended periods. These include the remains of a child with a congenital brain abnormality who was not abandoned but lived until five or six years old.
Stage 4 - In modern humans starting 120,000 years ago, compassion was extended to strangers, animals, objects and abstract concepts.
Dr Penny Spikins, lead author of the study, said that new research developments, such as neuro-imaging, have enabled archaeologists to attempt a scientific explanation of what were once intangible feelings of ancient humans – and that the research was only the first step in a much needed prehistoric archaeology of compassion.
“Compassion is perhaps the most fundamental human emotion. It binds us together and can inspire us but it is also fragile and elusive,” said Dr Spikins. “This apparent fragility makes addressing the evidence for the development of compassion in our most ancient ancestors a unique challenge, yet the archaeological record has an important story to tell about the prehistory of compassion.”
Dr Spikins will give a free lecture, 'Neanderthals in love: What can archaeology tell us about the feelings of ancient humans', about the research at the University of York on Tuesday 19 October.
For more, including their new book, see http://heritage-key.com/blogs/ann/prehistory-compassion-neanderthals-cared-too.
[ This message was edited by: bat400 on 2010-10-08 04:42 ]
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bat400
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| Posted 08-10-2010 at 04:45
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On 2010-10-08 04:41,
The Prehistory of Compassion: Neanderthals Cared Too
Submitted by coldrum --
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And also from coldrum, a slightly different article on the same subject: http://news.discovery.com/human/neanderthals-were-compassionate-and-caring.html
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coldrum
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| Posted 21-11-2010 at 13:08
Fossil Teeth of Neanderthals Reveal Fast Track to Maturity
Modern humans benefit from slower growth, longer lives, researchers say.
Children today take longer to mature than Neanderthal children did, which may have given modern humans an evolutionary advantage, researchers suggest.
In the study, a multinational team of scientists used synchrotron X-ray imaging to study the fossil teeth of young Neanderthals and Homo sapiens.
"Teeth are remarkable time recorders, capturing each day of growth much like rings in trees reveal yearly progress. Even more impressive is the fact that our first molars contain a tiny 'birth certificate' and finding this birth line allows us to calculate exactly how old a juvenile was when it died," Tanya Smith, a researcher at Harvard University and the Max-Planck Institute for Evolutionary Anthropology, said in a news release from the European Synchrotron Radiation Facility.
The fossil teeth were analyzed at the facility, located in France. The scientists found that Neanderthal teeth grew much faster than the teeth of modern humans.
The longer maturation process in modern human children may lead to additional learning and complex cognition, giving humans a competitive advantage over Neanderthals, the study authors noted.
The shift from a primitive "live fast and die young" strategy to a "live slow and grow old" strategy has helped make modern humans one of the most successful organisms on the planet, according to the scientists.
The study was published in this week's online issue of the Proceedings of the National Academy of Sciences.
http://www.businessweek.com/lifestyle/content/healthday/646125.html
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coldrum
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| Posted 21-11-2010 at 13:09
Questions arise over earliest evidence of human tool use
The debate over when our ancestors first used stone tools is not over just yet. In August, researchers had reported finding scratch marks on two 3.4-million-year-old animal bones that they said were made by Australopithecus afarensis — the ancestor made famous by Lucy — scraping meat off the bones with sharp-edged stones. If true, that would push tool use back to 800,000 years earlier than previously thought. However, a new study challenges this interpretation and says that the marks were not made by early humans, but came instead from sediments grinding against the surface of the bones.
Two parallel cut marks possibly made by stone tools cutting into tissues on the rib of a cow-sized or larger ungulate.
© Dikika Research Project
Possibly stone tool-modified bones from Dikika, Ethiopia.
© Dikika Research Project
Shannon McPherron, a Paleolithic archaeologist at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and his team found the bones in question in the Dikika area in Ethiopia. In August, McPherron and his team authored a paper in Nature stating that the marks resemble butchery cuts.
But figuring out what caused scratch marks on fossil animal bones is a tricky issue, says Henry Bunn, a paleoanthropologist at the University of Wisconsin at Madison and a member of the team criticizing the initial study. Both hominin butchery and trampling — either from animals stepping on bones or from sediments grinding against them — can cause deep grooves and fine scratches on bones, he says. However, experiments with modern bones have enabled scientists to distinguish between those types of cuts — for example, Bunn says, V-shaped marks are characteristic of stone tool use, while trampling causes more rounded grooves.
Bunn and his colleagues say the marks on the 3.4-million-year-old bones resemble the types of damage characteristic for trampling. “It’s almost like a mirror image; the similarities are striking,” Bunn says. Bunn and his team also considered evidence other than the actual marks on the bones. For example, no sharp-edged stones were found at the Dikika site, they wrote in the Proceedings of the National Academy of Sciences. That makes it hard to explain how hominins could have produced stone tool marks. “There are no bigger pieces of stone that would be graspable by a hominin, whether we are talking about intentionally produced flakes or naturally broken but unmodified pieces of rock,” Bunn says.
Another issue is the exact location where the bones came from, Bunn says. The team working at Dikika found the specimens on the surface and only know approximately which layer of sediment they were originally buried in. That matters because the type of sediment can determine whether trampling damage was even possible. “Did the bones originate in a very fine clay deposit, in which case there would be no natural sediments coarse and abrasive enough to cause the damage, or did the bones occur in a sandy deposit?” Bunn says. He and his team would like to see the Dikika research project team follow up by establishing where the bones came from and then excavating there.
The fact that Bunn and his team did not examine the actual bones, and instead based their analysis on the scanning electron microscope images published in the Nature paper, also makes their characterization of the marks difficult, McPherron says. “One of the issues that [Bunn and his team] raise is whether or not the marks have a V-shape to them and it’s obviously hard to show V-shapes in a photo,” McPherron says.
Richard Potts, a paleoanthropologist at Smithsonian’s National Museum of Natural History and the Human Origins Program in Washington, D.C., who was not involved in either study, agrees that additional evidence, such as the type of sediment and the presence of sharp stones, is important. “I would say that you need four things to make the extraordinary case of [stone tool use] 800,000 years earlier: sediments, tools, bones with marks on them, in the ground and in the same place.”
The answer to the question of whether the marks are actually butchery marks is unclear, Potts says. “What’s coming out from this [controversy] is that you can get two very good research groups who have been leaders in the field of identifying damage to fossil bones …. and they disagree. That basically says that the criteria for recognizing and distinguishing these kinds of marks are not as yet good enough.”
Nicole Branan
http://www.earthmagazine.org/earth/article/3c8-7da-b-12
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coldrum
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| Posted 21-11-2010 at 13:14
New statistical model moves human evolution back 3 million years
Evolutionary divergence of humans from chimpanzees likely occurred some 8 million years ago rather than the 5 million year estimate widely accepted by scientists, a new statistical model suggests.
The revised estimate of when the human species parted ways from its closest primate relatives should enable scientists to better interpret the history of human evolution, said Robert D. Martin, curator of biological anthropology at the Field Museum, and a co-author of the new study appearing in the journal Systematic Biology.
Working with mathematicians, anthropologists and molecular biologists, Martin has long sought to integrate evolutionary information derived from genetic material in various species with the fossil record to get a more complete picture.
Comparing DNA among related animals can provide a clear picture of how their shared genes evolved over time, giving rise to new and separate species, Martin said. But such molecular information doesn't yield a timetable showing when the genetic divergence occurred.
Fossil evidence is the only direct source of information about long-extinct species and their evolution, Martin and his colleagues said, but large gaps in the fossil record can make such information difficult to interpret. For a generation, paleontologists have estimated human origins at 5 million to 6 million years ago.
But that estimate rests on a thin fossil record. By looking at all of today's primate species, all of the known fossil primates and using DNA evidence, computer models suggest a longer evolutionary timetable. The new analysis described in the Systematic Biology paper takes into account gaps in the fossil record and fills in those gaps statistically.
Such modeling techniques, which are widely used in science and commerce, take into account more overall information than earlier processes used to estimate evolutionary history using just a few individual fossil dates, Martin said. It can give scientists a broader perspective for interpreting data.
One example is a skull fossil discovered in Chad (central Africa) earlier in this decade. The fossil, named Sahelanthropus tchadensis and nicknamed Toumaï (which means "hope of life" in the local Goran language), raised great interest because it has many human characteristics. But consensus on how to classify the discovery has been elusive particularly because the fossil is about 7 million years old, well beyond the accepted time frame for human evolution.
Under the new estimate, Toumaï would fall within the period after the human lineage split from chimpanzees, Martin said.
The new approach to dating evolutionary history builds on earlier work by Martin and colleagues. In 2002, they published a paper in Nature that argues the last common ancestor of today's primates lived some 85 million years ago.
This implies that for 20 million years before dinosaurs became extinct, early versions of primates also lived and evolved. It challenged the accepted theory that primates and other mammals didn't really thrive on the planet until dinosaurs were gone.
After that paper was published, Martin said he expected someone would apply the new statistical techniques to the question of human evolution, but when no one did, "We decided to do it ourselves."
More information: Here is a link to the article: http://sysbio.oxfordjournals.org/content/early/2010/11/04/sysbio.syq054.full.html?ijkey=CaQif1LgTAd7xOD&keytype=ref
Provided by Field Museum
http://www.physorg.com/news/2010-11-statistical-human-evolution-million-years.html
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coldrum
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| Posted 21-11-2010 at 13:15
Stone Age humans needed more brain power to make big leap in tool design
Stone Age humans were only able to develop relatively advanced tools after their brains evolved a greater capacity for complex thought, according to a new study that investigates why it took early humans almost two million years to move from razor-sharp stones to a hand-held stone axe.
Researchers used computer modelling and tiny sensors embedded in gloves to assess the complex hand skills that early humans needed in order to make two types of tools during the Lower Palaeolithic period, which began around 2.5 million years ago. The cross-disciplinary team, involving researchers from Imperial College London, employed a craftsperson called a flintnapper to faithfully replicate ancient tool-making techniques.
The team say that comparing the manufacturing techniques used for both Stone Age tools provides evidence of how the human brain and human behaviour evolved during the Lower Palaeolithic period.
Neuroscientist Dr Aldo Faisal, the lead author of the study from the Departments of Bioengineering and Computing at Imperial College London, says: "The advance from crude stone tools to elegant hand-held axes was a massive technological leap for our early human ancestors. Hand-held axes were a more useful tool for defence, hunting and routine work. Interestingly, our study reinforces the idea that tool making and language evolved together as both required more complex thought, making the end of the Lower Palaeolithic a pivotal time in our history. After this period, early humans left Africa and began to colonise other parts of the world."
Prior to today's study, researchers have had different theories about why it took early humans more than 2 million years to develop stone axes. Some have suggested that early humans may have had underdeveloped motor skills or abilities, while others have suggested that it took human brains this time to develop more complex thoughts, in order to dream up better tool designs or think about better manufacturing techniques.
The researchers behind today's study say that their evidence, from studying both tool-making techniques, confirms that the evolution of the early human brain was behind the development of the hand-held axe. Furthermore, the team suggest that the advancement of hand-held axe production may have also coincided with the development of language, as these functions overlap in the same regions of the modern and early human brains.
The flintnapper who participated in today's study created two types tools including the razor-sharp flakes and hand-held axes. He wore a data glove with sensors enmeshed into its fabric to record hand and arm movements during the production of these tools.
After analysing this data, the researchers discovered that both flake and hand-held axe manufacturing techniques were equally complex, requiring the same kind of hand and arm dexterity. This enabled the scientists to rule out motor skills as the principal factor for holding up stone tool development.
The team deduced from their results that the axe-tool required a high level of brain processing in overlapping areas of the brain that are responsible for a range of different functions including vocal cords and complex hand gestures.
This is the first time that neuroscientists, archaeologists, anthropologists and flintnappers have teamed together, using cutting edge technology including data glove sensors and advanced modelling, to develop a deeper understanding of early human evolution.
In the future, the team plan to use their technology to compare tools made by Neanderthals, an extinct ancestor of humans, to glean insights into their brain development.
More information: "The manipulative complexity of Lower Palaeolithic stone tool making" PLoS One journal, Wednesday 3 November 2010.
http://www.physorg.com/news/2010-11-stone-age-humans-brain-power.html
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coldrum
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| Posted 21-11-2010 at 13:17
Neanderthals Were Promiscuous, Finger Fossils Suggest
Neanderthals, early apes and other ancient human species may have been much more promiscuous and competitive than we are today, according to an unusual new study based on finger fossils.
The fingers weren't found in compromising positions, although that would've made for some interesting photos. Instead, researchers used finger ratios from fossilized skeletal remains to make the determination.
It's a reworking of a technique that has been applied to everything from studies on sexual orientation to research on why some people are superstitious.
Neanderthalensis
(Neanderthal skeleton at the American Museum of Natural History. Note the fingers. Credit: Claire Houck)
The gist is that androgens -- a group of hormones important in the development of masculine characteristics -- are thought to affect finger length. High levels of the hormones are believed to increase the length of the fourth finger in comparison to the second finger, resulting in a low index to ring finger ratio.
Emma Nelson, from the University of Liverpool's School of Archaeology, Classics and Egyptology and her colleagues applied the digit ratio theory to fossilized finger bones from early apes, Neanderthals, and two other early hominids: Ardipithecus ramidus and Australopithecus afarensis.
A.afarensis
(Australopithecus afarensis recreation; Wikimedia Commons image)
Nelson and her team discovered that the fossil finger ratios of Neanderthals and early humans were lower than those of most living people. This suggests they had been exposed to high levels of prenatal androgens, indicating they were likely to be more competitive and promiscuous than people are today.
The results, published in the Proceedings of the Royal Society B, also suggest that Australopithecus, which lived approximately three to four million years ago, was likely monogamous, while the earlier Ardipithecus appears to have been highly promiscuous and more similar to living great apes.
Nelson explained, "It is believed that prenatal androgens affect the genes responsible for the development of fingers, toes and the reproductive system. We have recently shown that promiscuous primate species have low index to ring finger ratios, while monogamous species have high ratios."
She added, "We used this information to estimate the social behaviour of extinct apes and hominins. Although the fossil record is limited for this period, and more fossils are needed to confirm our findings, this method could prove to be an exciting new way of understanding how our social behavior has evolved."
Susanne Shultz from the Institute of Cognitive and Evolutionary Anthropology at the University of Oxford also worked on the study.
Shultz concluded, "Social behaviors are notoriously difficult to identify in the fossil record. Developing novel approaches, such as finger ratios, can help inform the current debate surrounding the social systems of the earliest human ancestors."
http://news.discovery.com/human/neanderthals-were-promiscuous-finger-fossils-suggest.html
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coldrum
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| Posted 21-11-2010 at 15:14
The brains of Neanderthals and modern humans developed differently
Researcher at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany have documented species differences in the pattern of brain development after birth that are likely to contribute to cognitive differences between modern humans and Neanderthals.
Whether cognitive differences exist between modern humans and Neanderthals is the subject of contentious disputes in anthropology and archaeology. Because the brain size range of modern humans and Neanderthals overlap, many researchers previously assumed that the cognitive capabilities of these two species were similar. Among humans, however, the internal organization of the brain is more important for cognitive abilities than its absolute size is. The brain’s internal organization depends on the tempo and mode of brain development.
Based on detailed measurements of internal shape changes of the braincase during individual growth, a team of scientists from the MPI has shown that these are differences in the patterns of brain development between humans and Neanderthals during a critical phase for cognitive development.
Discussions about the cognitive abilities of fossil humans usually focus on material culture (e.g. the complexity of the stone tool production process) and endocranial volumes. "The interpretation of the archaeological evidence remains controversial, and the brain-size ranges of Neanderthals and modern humans overlap," says Jean-Jacques Hublin, director of the Department of Human Evolution at the MPI-EVA in Leipzig where the research was conducted. Hublin adds, "our findings show how biological differences between modern humans and Neanderthals may be linked to behavioural differences inferred from the archaeological record."
Nature of the evidence: As the brain does not fossilize, for fossil skulls, only the imprints of the brain and its surrounding structures in the bone (so called "endocasts") can be studied. The researchers used state-of-the-art statistical methods to compare shape changes of virtual endocasts extracted from computed-tomographic scans. The distinct globular shape of the braincase of adult Homo sapiens is largely the result of a brain development phase that is not present in Neanderthals.
One of the key pieces of evidence was the skull reconstruction of a Neanderthal newborn. In 1914, a team of French archaeologists had excavated the skeleton of a Neanderthal baby at the rock shelter of Le Moustier in the Dordogne. The original bones of the skeleton had been lost to science for more than 90 years, until they were rediscovered among museum collections by Bruno Maureille and the museum staff. The restored original baby bones are now on permanent display at the Musée National de Préhistoire in Les Eyzies-de-Tayac-Sireuil. The museum’s director Jean-Jacques Cleyet-Merle made it possible to scan the delicate fragments using a high-resolution computed-tomographic scanner (µCT). Using computers at the Max Planck Institute’s virtual reality lab in Leipzig, Philipp Gunz and Simon Neubauer then reconstructed the Neanderthal baby from the digital pieces, like in a three-dimensional jigsaw puzzle. "When we compare the skulls of a Neanderthal and a modern human newborn, the Neanderthal’s face is already larger at the time of birth. However, most shape differences of the internal braincase develop after birth," explains Gunz. Both Neanderthals and modern human neonates have elongated braincases at the time of birth, but only modern human endocasts change to a more globular shape in the first year of life. Modern humans and Neanderthals therefore reach large adult brain sizes via different developmental pathways.
In a related study the same team of MPI researchers had previously shown that the developmental patterns of the brain were remarkably similar between chimpanzees and humans after the first year of life, but differed markedly directly after birth. "We interpret those aspects of development that are shared between modern humans, Neanderthals, and chimpanzees as conserved," explains Simon Neubauer. "This developmental pattern has probably not changed since the last common ancestor of chimpanzees and humans several million years ago." In the first year of life, modern humans, but not Neanderthals, depart from this ancestral pattern of brain development.
Establishing when the species differences between Neanderthal and modern human adults emerge during development was critical for understanding whether differences in the pattern of brain development might underlie potential cognitive differences. As the differences between modern humans and Neanderthals are most prominent in the period directly after birth, they likely have implications for the neuronal and synaptic organization of the developing brain.
The development of cognitive abilities during individual growth is linked to the maturation of the underlying wiring pattern of the brain; around the time of birth, the neural circuitry is sparse in humans, and clinical studies have linked even subtle alterations in early brain development to changes in the neural wiring patterns that affect behaviour and cognition. The connections between diverse brain regions that are established during this period in modern humans are important for higher-order social, emotional, and communication functions. It is therefore unlikely that Neanderthals saw the world as we do.
The new study shows that modern humans have a unique pattern of brain development after birth, which separates us from our closest relatives, the Neanderthals. This uniquely modern human pattern of early brain development is particularly interesting in light of the recent breakthroughs in the Neanderthal genome project. A comparison of Neanderthal and modern human genomes revealed several regions with strong evidence for positive selection within Homo sapiens, i.e. the selection occurred after the split between modern humans and Neanderthals. Three among these are likely to be critical for brain development, as they affect mental and cognitive development.
"Our findings have two important implications," says Philipp Gunz. "We have discovered differences in the patterns of brain development that might contribute to cognitive differences between modern humans and Neanderthals. Maybe more importantly, however, this discovery will tell us more about our own species than about Neanderthals; we hope that our findings will help to identify the function of some genes that show evidence for recent selection in modern humans."
http://goto.mpg.de/mpg/news/201011021/
Attached files
*
The brains of Neanderthals and modern humans are very similar at the time of birth. A reconstruction of a Neanderthal baby is compared to a modern human newborn. While the face of the Neanderthal is already larger than in a modern human at the time of birth, their brain shapes and volumes are very similar. Internal casts of brain cavities of skulls (Neanderthal: red; modern humans: blue) provide information about the relative size and form of the brain. Image: Max Planck Institute for Evolutionary Anthropology
http://www.alphagalileo.org/ViewItem.aspx?ItemId=89294&CultureCode=en
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Andy B
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| Posted 09-01-2011 at 17:20
Neanderthal face is not cold adapted
Researchers have reported in the Journal of Human Evolution that the long held belief that the Neanderthal nose was a result of adaptations to extreme cold may not be all it seems.
Many of the morphological features of Homo neanderthalensis, including the reputed large size of its paranasal sinuses, have been interpreted as adaptations to extreme cold, as some Neanderthals lived in Europe during glacial periods.
This interpretation of sinus evolution rested on two assumptions: that increased formation of air cells or cavities in the face, were an adaptation to lower ambient temperatures, and that Neanderthals have large sinuses relative to the modern human. However, the researchers from Roehampton University, Universität Greifswald and The Natural History Museum, London have conducted detailed analysis of humans, primates and rodents suggesting a very different picture
The new report shows the first assumption is at best suspect; with the maxillary sinus undergoing a significant reduction in volume in extreme cold, in both wild and laboratory conditions.
The second assumption – that Neanderthal sinuses are large, extensive, or even over developed has been accepted since the first specimen was described in the 19th century. This has been interpreted as the explanation for some of the distinctive aspects of Neanderthal facial form, but has never been evaluated with respect to scaling these cavities to other hominid forms.
Comparison between homo neanderthalis and homo sapies sapiens skullsTo test the second assumption, the researchers tested previously published measurements from two-dimensional X-rays and new three-dimensional data from computed tomography of Neanderthals and temperate-climate European Homo sapiens and then scaled the results against cranial size to determine the relative size of their sinuses.
The 2D data reveals Neanderthals sinus size is comparable in scale with that seen in temperate climate H. sapiens. The 3D analysis of CT data from a smaller sample also supported this conclusion.
These results suggest that the distinctive Neanderthal face cannot be interpreted as a direct result of increased sinus size as an adaptation to resist cold stress; and so an alternative explanation is required.
In 1997 Jeffrey Laitman, an anatomist at Mount Sinai Medical Centre in New York , asked the question if the Neanderthals’ highly specialised noses could have been a drawback once Europe’s climate warmed. In warm weather, a cavernous, sticky sinus might have been fertile ground for infection and with absolutely huge sinus systems how would this have affected the European Neanderthal.
Read more >> http://www.pasthorizons.com/index.php/archives/12/2010/neanderthal-face-is-not-cold-adapted#ixzz14bBB1YW1
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bat400
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| Posted 17-01-2011 at 22:27
Neanderthals fashioned earliest tool from human bone. Skull fragment dating back at least 50,000 years bears signs it was used as a sharpener.
Submitted by coldrum ---
The earliest known tool made from human bone has been discovered — and it was apparently crafted by Neanderthals, scientists find.
The scientists note that as of yet, they have no way to prove or disprove whether the Neanderthals who made the tool did so intentionally — for instance, for rituals or after cannibalization.
Until now, the first evidence that human bones were used either symbolically or as tools were 30,000-to 34,000-year-old perforated human teeth found at excavations in southwest France. These were apparently used as ornaments.
Now scientists have identified a human skull fragment dating back at least 50,000 years that bears signs it was used as a sharpener. It was found in a Neanderthal deposit — the first time our relatives were discovered making tools from human bone.
The bone was first unearthed in 1926 at the La Quina site, a former rock shelter at the foot of a limestone cliff flanking the left bank of the Voultron River in southwest France. It was discovered with artifacts from the Mousterian industry, a method of making flint tools linked with Neanderthals. These fragments did not yield much information about the anatomy of these individuals, so they were mostly ignored at the museum at Lyon, France.
Then paleoanthropologist Christine Verna (Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany,) reinvestigated all the human remains at La Quina. Using microscopic analysis of the bone fragment, she and her colleague Francesco d'Errico (University of Bordeaux, France) found evidence it was used to retouch stone tool edges. They also detected scraping marks on the fragment, possibly resulting from cleaning of the skull before it was broken into pieces. The bone likely came from a Neanderthal, as only they were found at Mousterian deposits at La Quina.
A number of animal bones on the site, (reindeer jaw, a horse tooth,) also showed evidence they were used as tools. However, none of the other retouchers from this site or any other known Mousterian site was ever made from skull fragments, apparently making this new discovery unique and perhaps suggesting the human bone was intentionally chosen for use as a tool.
"It could reflect that a human bone was not seen as any different from an animal one — that this human body was treated exactly like the fauna, in which case they were not attributing any symbolic meaning to this death," "Or it could reflect a particular process in which using this human bone as a tool had a special meaning, even though we don't know which one."
"These results remind us how little we know about the relationship these Paleolithic societies had with death, and that probably a high diversity existed in terms of treatment of the dead," Verna said. "Regarding Neanderthals, the debate usually focuses on the hypotheses of cannibalism and burial. We know that some Neanderthals were burying their dead, but that certainly reflects only a small part of a broad range of behaviors. It is unlikely that all groups of Neanderthals everywhere and during all their history were having the same mortuary practices."
Verna and d'Errico detailed their findings online Dec. 4 in the Journal of Human Evolution.
http://www.msnbc.msn.com/id/40718850/ns/technology_and_science-science/.
Coldrum also sent a link to a similar article at www.pasthorizons.com.
[ This message was edited by: bat400 on 2011-02-15 03:45 ]
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bat400
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| Posted 17-01-2011 at 23:12
Neanderthals: how needles and skins gave us the edge on our kissing cousins. The Neanderthal genome tells us we were very similar: in fact we interbred. But intellect and invention meant that we lived while they perished, says Robin McKie, of The Guardian.
Submitted by coldrum --
On the ground floor of the Natural History Museum in London, arrays of Formica-covered cabinets stretch from floor to ceiling and from one end of the great building to the other. Some of nature's finest glories are stored here: pygmy hippo bones from Sicily, mammoth tusks from Siberia and skulls of giant sloths from South America.
Many treasures compete for attention, but there is one sample, kept in a small plywood box, that deserves especial interest: the Swanscombe skull. Found near Gravesend last century, it is made up of three pieces of the brain case of a 400,000-year-old female and is one of only half-a-dozen bits of skeleton that can be traced to men and women who lived in Britain before the end of the last ice age. Human remains do not get more precious than this.
However, the Swanscombe find is important for another, crucial reason: the skull is that of a Neanderthal, shadowy, evolutionary cousins of our own species who made complex stone tools and who once thrived in Europe before being wiped about 35,000 years ago, not long after modern humans had emerged from their African birthplace and had begun to spread across the planet.
"This woman was clearly a member of a very successful tribe of hunter-gatherers to judge from the thousands of stone axes they left behind at Swanscombe," says Professor Chris Stringer, research leader in human origins at the museum.
The reason for the Neanderthals' extinction has been pondered by scientists for 150 years without resolution. These bulky but brainy people have stubbornly refused to give up their secrets. However, a series of remarkable projects has recently shed new light on the Neanderthals and their relationship with modern humans. It is a remarkable story that takes us from London to France, Spain, eastern Europe and Africa and – most important of all – to the Max Planck Institute for Evolutionary Anthropology in Leipzig.
The contrast between the institute and the dusty glories of the Natural History Museum could not be greater. The central concourse of this huge glass and concrete building has been fitted with a climbing wall while a baby grand piano stands at its foot. "We are encouraged to breakfast, lunch and dine here and to swap ideas," explains geneticist Svante Pääbo. "We need to take our minds off things occasionally."
Certainly, its researchers deserve relaxation. Set up in 1997 and lavishly funded by the German government as part of its reunification of the country, the institute has already pioneered some striking research which culminated this year with completion of the sequencing of a Neanderthal genome.
By any account, this was an extraordinary undertaking. Scientists only succeeded in unravelling the three billion units of DNA that make up the human genome in 2000. Yet within 10 years, Pääbo did the same for a species that had died out more than 30,000 years ago using only bones from Vindija cave in Croatia as his source material. It was simply "fabulous" research, says Ian Tattersall of the American Museum of Natural History.
To create the genome, Pääbo and his team used dentists' drills to extract pill-sized samples of bone cells which were then broken up to reveal the DNA in their nuclei. The risk of researchers contaminating samples with their own DNA required them to wear full-body suits, masks and gloves all the time while air pressure in the laboratory was kept high so no contamination could blow in. And when the team went home, the room was irradiated.
It was a draining, four-year effort. Pääbo outlined the 60% complete Neanderthal genome in May.
However, there was an added sensational aspect to Pääbo's work. He compared his Neanderthal genome with those of five modern humans, from South Africa, western Africa, France, China and New Guinea and found the last three possessed small amounts of Neanderthal DNA. The explanation is intriguing.
At some point during humanity's exodus from Africa, interbreeding between the two species must have taken place, probably when they met 100,000 years ago as Homo sapiens began to move into Neanderthal territory in the Levant. Hence it appears in non-Africans but not in Africans. "Our work is not about understanding Neanderthals," added Ed Green, one of Pääbo's team. "It's about understanding us."
Certainly, the notion that modern humans and Neanderthals were not just evolutionary cousins but were evolutionary kissing cousins does suggest differences between us may have been relatively slight. We had to be close to interbreed, surely? Thus it was just bad luck that doomed them and not us, a point stressed by Clive Finlayson, of the Gibraltar Museum.
He describes Neanderthals as expert ambush hunters who used thick vegetation to stalk their prey. By contrast, modern humans, who had evolved on the African savannah, were better long-distance runners who could chase their prey over open land. Crucially, as modern humans – or Cro-Magnons – entered Europe, climatic change began thinning its dense woodlands and opening up the landscape, giving them a key advantage over Neanderthals. "The roulette wheel of life favoured one and not the other. A slight change of time, place, climate or fortunes and a Neanderthal might have been writing these lines," Finlayson wrote recently in the Times.
In short, we just got lucky. Apart from some differences in physique and behaviour, we were really very close to one another, it is argued. Yet many other scientists dispute this idea and point to a series of recent studies which undermine notions that Neanderthals were the intellectual equals of modern humans. A powerful example is provided by Tom Higham (Oxford Radiocarbon Accelerator Unit) who used new dating techniques to study artefacts found at Grotte du Renne.
In the 1950s, archaeologists in central France dug up delicately carved pieces of bone and pierced teeth that had been worn as necklaces. These were attributed – by studying soil layers – to Neanderthal craftsmen and hailed as clear demonstrations of their artistic genius and capacity for symbolic expression. In fact, the artefacts are just about the only evidence so far uncovered which shows Neanderthals had artistic and symbolic talents. Hence the importance of Grotte du Renne.
Higham's work was published in the Proceedings of the US National Academy of Sciences last month and made uncomfortable reading for many researchers. He found that some pieces of Grotte du Renne jewellery that were attributed to Neanderthal "craftsmen" were only 21,000 years old – 10,000 years after the last Neanderthal had died.
In fact, it is now clear that layers of soil must have become mixed up over the millennia and that delicate artwork attributed to Neanderthals was the handiwork of Cro-Magnons. "The single most impressive and widely cited pillar of evidence for the presence of complex symbolic behaviour among the Neanderthal populations in Europe has now effectively collapsed," says Paul Mellars (University of Cambridge.)
In short, the idea that Neanderthals possessed the same capacity for sophisticated expression and thought as modern humans received a possibly mortal blow, raising serious questions about their intellectual prowess and ability to withstand their rivals, Homo sapiens. It seems clear that an "intellectual and social gulf" separated them from Homo sapiens, says archaeologist Brian Fagan, in his new book, Cro-Magnon. "What gave our ancestors the edge was their intellectual awareness and imagination, their ability not only to co-operate with others but also to plan ahead and think of their surroundings." We were a class apart, in other words.
But which specific traits gave us such an advantage at the expense of the Neanderthals? In the suite of behaviours that we evolved in Africa 150,000 years ago, what were the characteristics that really made a difference and can therefore be considered as defining human attributes? There are many candidates – complex language and superior memory, for example. However, among many scientists there appears to be consensus that imagination and opportunism were critical attributes.
This meant, says Fagan, that we learned to use local materials – antler, bone and ivory – in ways Neanderthals simply could not imagine. In one case, this resulted in "one of the most revolutionary inventions in history: the eyed needle, fashioned from a sliver of bone or ivory," he adds. While Neanderthals shivered in rags in winter, humans used vegetable fibres and needles to make close-fitting, layered clothing and parkas: the survival of the snuggest.
A slightly different interpretation is given by Steve Churchill of Duke University, in North Carolina. He believes it was the invention of the first projectile weapons that really did it for Homo sapiens. Spear-throwers allowed hunters to hurl projectiles with greatly improved accuracy and distance. The consequences of these inventions were profound. It meant Cro-Magnons could kill animals from a considerable – and rather safe – distance of between 20 and 40 metres. Neanderthals continued to fight close up and personal, often to their cost. "Spear-throwers meant you could fire a couple of shots off and not worry about being stamped on or trampled by an angry mammoth," says Churchill.
Stringer agrees: "If early modern humans had better ways of coping with rapid climate change, such as sewn clothing and more efficient weapons, they would have been more likely to survive. That is not to say modern humans always survived, since populations of both species only existed in their thousands in Europe then. Nevertheless, we multiplied and the Neanderthals did not."
http://www.guardian.co.uk/science/2010/dec/05/neanderthals-genome-anthropology
[ This message was edited by: bat400 on 2011-01-18 03:42 ]
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bat400
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| Posted 12-02-2011 at 20:24
US study finds Neanderthals ate their veggies
A US study on Monday found that Neanderthals, prehistoric cousins of humans, ate grains and vegetables as well as meat, cooking them over fire in the same way homo sapiens did. The new research published in the Proceedings of the National Academy of Sciences (PNAS) challenges a prevailing theory that Neanderthals' over reliance on meat contributed to their extinction around 30,000 years ago.
Researchers found grains from numerous plants, including a type of wild grass, as well as traces of roots and tubers, trapped in plaque buildup on fossilized Neanderthal teeth unearthed in northern Europe and Iraq.
Many of the particles "had undergone physical changes that matched experimentally-cooked starch grains, suggesting that Neanderthals controlled fire much like early modern humans," PNAS said in a statement.
Stone artifacts have not provided evidence that Neanderthals used tools to grind plants, suggesting they did not practice agriculture, but the new research indicates they cooked and prepared plants for eating, it said.
The squat, low-browed Neanderthals lived in parts of Europe, Central Asia and the Middle East for around 170,000 years but all evidence of them disappears some 28,000 years ago, their last known refuge being Gibraltar. Why they died out is a matter of debate, because they co-existed alongside modern man.
The latest study was carried out by the Department of Anthropology at the Smithsonian natural history museum in Washington.
Thanks to colrum for the link: http://news.yahoo.com/s/afp/20101227/ts_alt_afp/usanthropologyfoodneanderthals_20101227201706
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