Neanderthals and humans had 'ample time' to mix

[Buster's Uncle]

Neanderthals and humans had 'ample time' to mix
Associated Press
By FRANK JORDANS  1 hour ago



This Jan. 8, 2003 file photo shows a reconstructed Neanderthal skeleton, right, and a modern human version of a skeleton, left, on display at the Museum of Natural History in New York. Humans and Neanderthals may have coexisted in Europe for more than 5,000 years, providing ample time for the two species to meet and mix, according to new research. Using new carbon dating techniques and mathematical models, the researchers examined about 200 samples found at 40 sites from Spain to Russia. (AP Photo/Frank Franklin II, FILE)



BERLIN (AP) — Humans and Neanderthals may have coexisted in Europe for more than 5,000 years, providing ample time for the two species to meet and mix, according to new research.

Using new carbon dating techniques and mathematical models, researchers examined about 200 samples found at 40 sites from Spain to Russia, according to a study published Wednesday in the journal Nature. They concluded with a high probability that pockets of Neanderthal culture survived until between 41,030 and 39,260 years ago.

Although this puts the disappearance of Neanderthals earlier than some scientists previously thought, the findings support the idea that they lived alongside humans, who arrived in Europe about 45,000-43,000 years ago.

"We believe we now have the first robust timeline that sheds new light on some of the key questions around the possible interactions between Neanderthals and modern humans," said Thomas Higham, an archaeologist at the University of Oxford who led the study.

While it's known that Neanderthal genes have survived in the DNA of many modern humans to this day, suggesting that at least some interbreeding took place, scientists are still unclear about the extent of their contact and the reasons why Neanderthals vanished.

"These new results confirm a long-suspected chronological overlap between the last Neanderthals and the first modern humans in Europe," said Jean-Jacques Hublin, director of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, who wasn't involved in the study.

Apart from narrowing the length of time that the two species existed alongside each other to between 2,600 and 5,400 years, Higham and his colleagues also believe they have shown that Neanderthals and humans largely kept to themselves.

"What we don't see is that there is spatial overlap (in where they settled)," said Higham.

This is puzzling, because there is evidence that late-stage Neanderthals were culturally influenced by modern humans. Samples taken from some Neanderthal sites include artifacts that look like those introduced to Europe by humans migrating from Africa.

This would point to the possibility that Neanderthals — whose name derives from a valley in western Germany — adopted certain human habits and technologies even as they were being gradually pushed out of their territory.

"I think they were eventually outcompeted," said Higham.

Wil Roebroeks, an archaeologist at Leiden University in the Netherlands, cautioned that the study relies to a large decree on testing of stone tools, rather than bones, and these haven't been conclusively linked to particular species, or hominins.

"The results of this impressive dating study are clear, but the assumptions about the association of stone artefact with hominin types underlying the interpretation of the dating results will be undoubtedly rigorously tested in field- and laboratory work over the near future," said Roebroeks, who wasn't involved in the study. "Such testing can now be done with a chronologically clean slate."


http://news.yahoo.com/neanderthals-humans-had-ample-time-mix-170128726.html

[Buster's Uncle]

Humans Did Not Wipe Out the Neanderthals, New Research Suggests
LiveScience.com
By Charles Q. Choi, Live Science Contributor  1 hour ago



A site in Abric Romani, Spain, where Neanderthal remains were found.



Neanderthals went extinct in Europe about 40,000 years ago, giving them millennia to coexist with modern humans culturally and sexually, new findings suggest.

This research also suggests that modern humans did not cause Neanderthals to rapidly go extinct, as some researchers have previously suggested, scientists added.

Neanderthals are the closest extinct relatives of modern humans, and lived in Europe and Asia. Recent findings suggest that Neanderthals were closely related enough to interbreed with ancestors of modern humans — about 1.5 to 2.1 percent of the DNA of anyone outside Africa is Neanderthal in origin.

It has long been uncertain when Neanderthals went extinct, and there has been much debate over whether interactions with modern humans might have driven their disappearance. Neanderthals entered Europe before modern humans did, and prior studies had suggested the last of the Neanderthals held out there on the Iberian Peninsula until about 35,000 years ago, potentially sharing the region with modern humans for millennia. However, more recent findings suggested that some Neanderthal fossils from Europe might be thousands of years older than previously thought, raising the possibility that Neanderthals went extinct before modern humans arrived in Europe starting about 42,000 years ago.

To help solve the mystery of when Neanderthals went extinct, scientists analyzed bone, charcoal and shell materials from 40 archaeological sites from Russia to Spain. They employed advanced techniques for more precise dating of these specimens that involved ultra-filtering molecules from bone samples for examination and removing organic contaminants that could make specimens seem younger than they actually are.

The new findings suggest that Neanderthals disappeared from Europe between about 41,000 and 39,000 years ago.

"I think that, for the first time, we have a reliable extinction date for Neanderthals," said study author Tom Higham, a radiocarbon scientist at the University of Oxford in England. "This has eluded us for decades."

The Neanderthal extinction occurred across sites ranging from the Black Sea to the Atlantic Coast of Europe. The timing and geography suggest Neanderthals may have overlapped with modern humans for 2,600 to 5,400 years, opening the door for genetic and cultural exchanges between the two groups for millennia.

These findings suggest that modern humans did not rapidly replace Neanderthals in Europe — say, via violent means. Rather, the Neanderthal extinction "might have been more complex and drawn out than previously thought," Higham told Live Science.

There is some genetic evidence that Neanderthals in Western Europe may have experienced declining genetic diversity about the time when the first modern humans began arriving on the continent, Higham said. "This might mean that they were fading out at this time, although, of course, our evidence suggests that there was a long period of overlap during which this occurred," he said.

Neanderthals may not even have truly disappeared, but instead have been assimilated into modern human populations. "We know, of course, that we have a genetic legacy from Neanderthals of about 1 to 2 percent, so there was interbreeding," Higham said.

One mystery regarding sex between Neanderthals and modern humans is that the greatest amount of interbreeding between the two lineages is currently thought to have occurred about 77,000 to 114,000 years ago, preceding any potential interbreeding in Europe. However, Higham noted more recent as-yet-unpublished data suggest the interbreeding events occurred about 55,000 to 60,000 years ago, more in tune with interbreeding scenarios involving Europe. "What is needed is more genetic analysis of human bone from this transitional period in Europe," Higham said.

In the future, the researchers plan to extend their work into Eastern Europe and wider Eurasia to widen their data set and look for more patterns in the data pertaining to the Neanderthal extinction and the spread of modern humans, Higham said.

The scientists detailed their findings in the Aug. 21 issue of the journal Nature.


http://news.yahoo.com/humans-did-not-wipe-neanderthals-research-suggests-170427549.html

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Humans, Neanderthals shared Europe for millennia
AFP
29 minutes ago



Visitors look at a scientifically based impression of the face of a Neanderthal who lived some 50,000 years ago at an exhibition at the Museum of Human Evolution in Burgos on June 10, 2014 (AFP Photo/Cesar Manso)



Paris (AFP) - Neanderthals shared Europe with modern humans for as long as five millennia until they died out 40,000 years ago -- "ample time" for cultural exchanges and interbreeding, researchers said on Wednesday.

While there is no evidence that the two groups lived closely together, they did co-exist for anything from 25 to 250 generations, depending on the region, according to a paper published in the journal Nature.

"The results reveal a significant overlap of 2,600–5,400 years," wrote the researchers, who used improved technology to date about 200 samples of bone, charcoal and shell from 40 archaeological sites from Russia to Spain.

This was "ample time for interaction and interbreeding," said a press statement.

In the latest attempt to date our cousins' final moments on Earth, the team found that Neanderthals disappeared at different times from different parts of Europe instead of being replaced by humans at one fell swoop.

The question of how, why and when Neanderthals became extinct, leaving humans to take over, has long fascinated scientists. Some have postulated a much more recent disappearance.



Men look at a scientifically based impression of the skeleton of a Neanderthal who lived some 50,000 years during an exhibit at a museum in Burgos on June 10, 2014 (AFP Photo/Cesar Manso)


Anatomically-modern humans, having originated in Africa, reached Europe between 50,000 and 30,000 years ago, finding Neanderthals there. Their brief interaction resulted in non-African people today carrying about 1.5-2.1 percent Neanderthal DNA.

According to the new, six-year study, Europe 45,000 years ago was still occupied mainly by Neanderthals with small pockets of humans in between.

This balanced shifted over the following 5,000 years, until the Neanderthals eventually disappeared, the paper said.

Rather than modern humans abruptly replacing their distant cousins, there appears to have been a progressive change "characterised by a biological and cultural mosaic that lasted for several thousand years," the researchers wrote.

They said theirs was the most accurate dating yet of this period in history.

Reliable radiocarbon dating is often rendered difficult by the degradation of carbon in bone or rock samples older than 25,000 years.

"Previous radiocarbon dates have often underestimated the age of samples from sites associated with Neanderthals because the organic matter was contaminated with modern particles," said study leader Thomas Higham of Oxford University.

"We used ultrafiltration methods, which purify the extracted collagen from bone, to avoid the risk of contamination.

"This means we can say with more confidence that we have finally resolved the timing of the disappearance of our close cousins, the Neanderthals."

The study did not reach a conclusion on whether there had been a single human-Neanderthal interbreeding event, or several over time.

"Of course the Neanderthals are not completely extinct, because some of their genes are in most of us today," said Higham.


http://news.yahoo.com/humans-neanderthals-shared-europe-millennia-185117567.html

[Buster's Uncle]

Our life with the Neanderthals was no brief affair
Reuters
By Ben Hirschler  1 hour ago



An exhibit shows the life of a neanderthal family in a cave in the new Neanderthal Museum in the northern town of Krapina February 25, 2010. REUTERS/Nikola Solic



LONDON (Reuters) - Far from wiping out Neanderthals overnight, modern humans rubbed along with their shorter and stockier cousins for thousands of years, giving plenty of time for the two groups to share ideas - and have sex.

The most accurate timeline yet for the demise of our closest relatives, published on Wednesday, shows Neanderthals overlapped with present-day humans in Europe for between 2,600 and 5,400 years before disappearing about 40,000 years ago.

Pinpointing how and when the Neanderthals became extinct has been tough because the mainstay process of radiocarbon dating is unreliable for samples that are more than 30,000 years old, due to contamination.

The latest six-year project by researchers at the University of Oxford used modern methods to remove contaminants and accurately date nearly 200 samples of bone, charcoal and shell from 40 important archaeological sites across Europe.

The data showed that Neanderthals vanished from Europe between 39,000 and 41,000 years ago - but rather than being replaced rapidly by modern humans, their disappearance occurred at different times across sites from the Black Sea to the Atlantic.

"Now that we are using better techniques, the picture is becoming much more clear in terms of the process by which Neanderthals disappeared from Europe," said lead researcher Tom Higham. "Our results suggest there was a mosaic of populations."

Scientists already know from DNA evidence that there was some interbreeding between the two groups, although it is not clear whether this occurred once or many times. Recent studies have suggested between 1.5 and 2.1 percent of the DNA of modern non-African human populations originates from Neanderthals.

"In a way, our close cousins, as Neanderthals are, aren't extinct," according to Higham. "They carry on in us today."

Paleoanthropologist Chris Stringer of the Natural History Museum in London, who was not involved in the research, said the new findings were "striking" and backed up the idea that modern humans and Neanderthals may have learnt from each other.

He believes interbreeding probably first occurred in Asia soon after modern humans began to leave Africa around 60,000 years ago, so the latest evidence indicates the two populations may have been in some kind of contact for up to 20,000 years - much longer than in Europe alone.


NOT SO DIM-WITTED

Many scientists now reject the notion that Neanderthals were dim-witted brutes and point to evidence of use of symbolic objects, which may have been learnt from modern humans.

The Oxford team dated a number of items from sites of so-called transitional stone tool industries - viewed as either the work of the last of the Neanderthals or early modern humans - and found they were all between 40,000 and 45,000 years old, indicating a period of possible cultural exchange.

Interestingly, they found no evidence that Neanderthals and modern humans lived particularly closely together. Rather, Neanderthals probably survived in dwindling populations in pockets of Europe before dying out altogether.

It is unclear what killed off the Neanderthals, although theories include an inability to adapt to climate change and increased economic competition from more agile modern humans.

While the latest work provides the most robust timeline so far of the last days of the Neanderthals, there are still gaps in coverage, particularly in Siberia and eastern regions of Eurasia. That is something the researchers plan to address in follow-up investigations.

"Ultimately, our aim is to create kind of movies that show the arrival and departure of different sub-species of humans across Europe," Higham said in an interview filmed in his lab. "We are part-way towards that but there is a still a lot more work we can do."

Some scientists have hypothesized that late-surviving groups of Neanderthals lived in places such as Gibraltar after 40,000 years ago, but the latest dating provides no evidence of this, according to the Oxford team, whose findings were published in the journal Nature.

(editing by David Stamp)


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