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Another Nail in the Coffin for "Out of Africa" Theory

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Hobbits 'evolved separate to humans',23599,25862805-29277,00.html

AUSTRALIAN research has thrown a question mark over long-held beliefs of human evolution thanks to never-before-tried technology on a set of "hobbit bones'' found in Indonesia.

Researchers based in Canberra and Wollongong set to work on a "hobbit'' skeleton found on the Indonesian island of Flores in 2004, using new cladistic analysis.

It compares the forms of organisms to determine ancestral relationships - the first time it was used on this set of homo floresiensis bones.

The results were surprising.

Anthropologist Debbie Argue concluded the bones diverged from the Homo sapiens evolutionary line nearly two million years ago, meaning that it did not share an immediate ancestor with modern humans.

The homo floresiensis bones have previously been dismissed as the remains of a sick human or near-human impacted by environmental factors.

''(The results) suggests that H. floresiensis was not a sick modern human, not even a very close relative,'' Dr Argue said.

It would then also dispute the theory that Homo sapiens were the only hominin around after the Neanderthals, she said.

The research has been published in the Journal of Human Evolution.

Pesky science. Always conflicting with the "politically correct".

--- Quote ---A skull that rewrites the history of man

It has long been agreed that Africa was the sole cradle of human evolution. Then these bones were found in Georgia...

By Steve Connor, Science Editor

Wednesday, 9 September 2009

The conventional view of human evolution
and how early man colonised the world has been thrown into doubt by a series of stunning palaeontological discoveries suggesting that Africa was not the sole cradle of humankind. Scientists have found a handful of ancient human skulls at an archaeological site two hours from the Georgian capital, Tbilisi, that suggest a Eurasian chapter in the long evolutionary story of man.

The skulls, jawbones and fragments of limb bones suggest that our ancient human ancestors migrated out of Africa far earlier than previously thought and spent a long evolutionary interlude in Eurasia before moving back into Africa to complete the story of man.

Experts believe fossilised bones unearthed at the medieval village of Dmanisi in the foothills of the Caucuses, and dated to about 1.8 million years ago, are the oldest indisputable remains of humans discovered outside of Africa.
Related articles

    * Steve Connor: The story of humans unravels

But what has really excited the researchers is the discovery that these early humans (or "hominins") are far more primitive-looking than the Homo erectus humans that were, until now, believed to be the first people to migrate out of Africa about 1 million years ago.

The Dmanisi people had brains that were about 40 per cent smaller than those of Homo erectus and they were much shorter in stature than classical H. erectus skeletons, according to Professor David Lordkipanidze, general director of the Georgia National Museum. "Before our findings, the prevailing view was that humans came out of Africa almost 1 million years ago, that they already had sophisticated stone tools, and that their body anatomy was quite advanced in terms of brain capacity and limb proportions. But what we are finding is quite different," Professor Lordkipanidze said.

"The Dmanisi hominins are the earliest representatives of our own genus Homo outside Africa, and they represent the most primitive population of the species Homo erectus to date. They might be ancestral to all later Homo erectus populations, which would suggest a Eurasian origin of Homo erectus."

Speaking at the British Science Festival in Guildford, where he gave the British Council lecture, Professor Lordkipanidze raised the prospect that Homo erectus may have evolved in Eurasia from the more primitive-looking Dmanisi population and then migrated back to Africa to eventually give rise to our own species, Homo sapiens modern man.

"The question is whether Homo erectus originated in Africa or Eurasia, and if in Eurasia, did we have vice-versa migration? This idea looked very stupid a few years ago, but today it seems not so stupid," he told the festival.

The scientists have discovered a total of five skulls and a solitary jawbone. It is clear that they had relatively small brains, almost a third of the size of modern humans. "They are quite small. Their lower limbs are very human and their upper limbs are still quite archaic and they had very primitive stone tools," Professor Lordkipanidze said. "Their brain capacity is about 600 cubic centimetres. The prevailing view before this discovery was that the humans who first left Africa had a brain size of about 1,000 cubic centimetres."

The only human fossil to predate the Dmanisi specimens are of an archaic species Homo habilis, or "handy man", found only in Africa, which used simple stone tools and lived between about 2.5 million and 1.6 million years ago.

"I'd have to say, if we'd found the Dmanisi fossils 40 years ago, they would have been classified as Homo habilis because of the small brain size. Their brow ridges are not as thick as classical Homo erectus, but their teeth are more H. erectus like," Professor Lordkipanidze said. "All these finds show that the ancestors of these people were much more primitive than we thought. I don't think that we were so lucky as to have found the first travellers out of Africa. Georgia is the cradle of the first Europeans, I would say," he told the meeting.

"What we learnt from the Dmanisi fossils is that they are quite small between 1.44 metres to 1.5 metres tall. What is interesting is that their lower limbs, their tibia bones, are very human-like so it seems they were very good runners," he said.

He added: "In regards to the question of which came first, enlarged brain size or bipedalism, maybe indirectly this information calls us to think that body anatomy was more important than brain size. While the Dmanisi people were almost modern in their body proportions, and were highly efficient walkers and runners, their arms moved in a different way, and their brains were tiny compared to ours.

"Nevertheless, they were sophisticated tool makers with high social and cognitive skills," he told the science festival, which is run by the British Science Association.

One of the five skulls is of a person who lost all his or her teeth during their lifetime but had still survived for many years despite being completely toothless. This suggests some kind of social organisation based on mutual care, Professor Lordkipanidze said.
--- End quote ---

(TROLL) Dmanisi replica:

(APE)  Homo Habilis replica

Article Source:

Exerp: "The question is whether Homo erectus originated in Africa or Eurasia, and if in Eurasia, did we have vice-versa migration? This idea looked very stupid a few years ago, but today it seems not so stupid," he told the festival.

Comment:   I would be thrilled to find out that the H.E originated from Eurasia..

Exerp: "What we learn from the Dmanisi fossils is that they are quite small – between 1.44 metres to 1.5 metres tall. What is interesting is that their lower limbs, their tibia bones, are very human-like so it seems they were very good runners," he said.

He added: "In regards to the question of which came first, enlarged brain size or bipedalism, maybe indirectly this information calls us to think that body anatomy was more important than brain size. While the Dmanisi people were almost modern in their body proportions, and were highly efficient walkers and runners, their arms moved in a different way, and their brains were tiny compared to ours.

Comment:   I have learned from a documentary called "what makes us human" that it is not entirly the SIZE of the brain that makes us human. The amount of GREY MATTER we have is in relation to the kind of social environment we are designed for. Ants have a higher brain to skull ratio than humans do and they live in huge colonies.. Modern human brains are designed for social colonies of about 120 to 150. 

Link to documentary:

Video: What Makes Us Human? (1. Big Heads)
Update: Video Removed

There are also parts to the brain besides grey matter which play a role in our human characteristics and abilities. A smaller brain may be indication that Dmanisi species was designed to be a loner.

Human ancestors in Eurasia earlier than thought

Stone fragments found in Georgia suggest Homo erectus  might have evolved outside Africa.

Archaeologists have long thought that Homo erectus, humanity's first ancestor to spread around the world, evolved in Africa before dispersing throughout Europe and Asia. But evidence of tool-making at the border of Europe and Asia is challenging that assumption.

Reid Ferring, an anthropologist at the University of North Texas in Denton, and his colleagues excavated the Dmanisi site in the Caucasus Mountains of Georgia. They found stone artefacts mostly flakes that were dropped as hominins knapped rocks to create tools for butchering animals lying in sediments almost 1.85 million years old. Until now, anthropologists have thought that H. erectus  evolved between 1.78 million and 1.65 million years ago after the Dmanisi tools would have been made.

Furthermore, the distribution of the 122 artefacts paints a picture of long-term occupation of the area. Instead of all the finds being concentrated in one layer of sediment, which would indicate that hominins visited the site briefly on one occasion, the artefacts are spread through several layers of sediment that span the period between 1.85 million and 1.77 million years ago. The findings are published today in the Proceedings of the National Academy of Sciences1.

"This is indeed suggestive of a sustained regional population which had successfully adapted to the temperate environments of the southern Caucasus," explains Wil Roebroeks, an archaeologist at Leiden University in the Netherlands.

Eurasian ancestry?

 The presence of a tool-using population on the edge of Europe so early hints that the northern continent, rather than Africa, may have been the evolutionary birthplace of H. erectus. Unfortunately, the fossils of the hominins responsible for making the tools are not proving very helpful to the debate.

Fossilized bone fragments found in the same sedimentary layers as the Dmanisi artefacts are too weathered to be identified as belonging to any one species, so it is impossible to say for sure whether the tools were made by H. erectus.

Neither do fossil skulls previously retrieved from later sediments at the site help to resolve the controversy. These fossils, dating from 1.77 million years ago, had brains between 600 and 775 cubic centimetres in volume, whereas H. erectus  is generally thought to have had an average brain size of around 900 cubic centimetres. For comparison, modern humans have a brain capacity of around 1,350 cubic centimetres. "Many people call those Dmanisi fossils the earliest H. erectus, but there is still frequent debate about this," explains Ferring.

There and back again

 Even if the ancient inhabitants of the Dmanisi site were not early members of H. erectus, there is still a problem: anthropologists have previously thought that no hominins existed outside of Africa as early as 1.85 million years ago.

"Anthropology textbooks of the 1990s often showed maps with large arrows indicating migration of early H. erectus  from its inferred core area of eastern Africa to other parts of the Old World," explains Roebroeks. The findings in Dmanisi make such an explanation look faulty.

Ferring and his colleagues propose that some ancestors of H. erectus  might have travelled to Asia and possibly Europe, done a bit of evolving, then wandered back to Africa. [Exactly as explained in the book Erectus Walks Amongst Us ~ Cailen.]

"Remember, it would not have been obvious to the hominins they were leaving Africa. There were no signs saying 'You are leaving Africa now come and visit us again!'" says Bernard Wood, an anthropologist at the George Washington University in Washington DC. But Wood admits that it is unclear why the hominins might have made these movements. "It perplexes me," he says.

Ferring suggests that ancient hominins might have been following their food source animals. "My hunch is that the migrations relate to the rise of carnivory and a sudden flexibility to live and eat meat anywhere," he says. Vegetarians, he explains, are limited to the specific plants that sustain them and cannot travel from tropics to deserts to mountains nearly as easily as predators can. Wood agrees. "My guess is that hominins were following game," he says.

Other possibilities also exist. "We tend to think of hominins as living in a disease-free world, but maybe they were eliminated in some places by an epidemic, and the only healthy ones left were at the edges of their distribution", who could then move back into the vacated areas, says Wood.

Arabian Artifacts May Rewrite 'Out of Africa' Theory

By Charles Choi | Wed, Nov 30, 2011

 Newfound stone artifacts suggest humankind left Africa traveling through the Arabian Peninsula instead of hugging its coasts, as long thought, researchers say.

Modern humans first arose about 200,000 years ago in Africa. When and how our lineage then dispersed has long proven controversial, but geneticists have suggested this exodus started between 40,000 and 70,000 years ago. The currently accepted theory is that the exodus from Africa traced Arabia's shores, rather than passing through its now-arid interior.

 However, stone artifacts at least 100,000 years old from the Arabian Desert, revealed in January 2011, hinted that modern humans might have begun our march across the globe earlier than once suspected.

 Now, more-than-100 newly discovered sites in the Sultanate of Oman apparently confirm that modern humans left Africa through Arabia long before genetic evidence suggests. Oddly, these sites are located far inland, away from the coasts.

 "After a decade of searching in southern Arabia for some clue that might help us understand early human expansion, at long last we've found the smoking gun of their exit from Africa," said lead researcher Jeffrey Rose, a paleolithic archaeologist at the University of Birmingham in England. "What makes this so exciting is that the answer is a scenario almost never considered."

Arabian artifacts

 The international team of archaeologists and geologists made their discovery in the Dhofar Mountains of southern Oman, nestled in the southeastern corner of the Arabian Peninsula.

 "The coastal expansion hypothesis looks reasonable on paper, but there is simply no archaeological evidence to back it up," said researcher Anthony Marks of Southern Methodist University, referring to the fact that an exodus by the coast, where one has access to resources such as seafood, might make more sense than tramping across the desert..

 On the last day of the research team's 2010 field season, the scientists went to the final place on their list, a site on a hot, windy, dry plateau near a river channel that was strewn with stone artifacts. Such artifacts are common in Arabia, but until now the ones seen were usually relatively young in age. Upon closer examination, Rose recalled asking, "Oh my God, these are Nubians what the heck are these doing here?"

 The 100-to-200 artifacts they found there were of a style dubbed Nubian Middle Stone Age, well-known throughout the Nile Valley, where they date back about 74,000-to-128,000 years. Scientists think ancient craftsmen would have shaped the artifacts by striking flakes off flint, leading to distinctive triangular pieces. This is the first time such artifacts have been found outside of Africa.

 Subsequent field work turned up dozens of sites with similar artifacts. Using a technique known as optically stimulated luminescence dating, which measures the minute amount of light long-buried objects can emit, to see how long they have been interred, the researchers estimate the artifacts are about 106,000 years old, exactly what one might expect from Nubian Middle Stone Age artifacts and far earlier than conventional dates for the exodus from Africa.

 "It's all just incredibly exciting," Rose said.

Arabian spring?

 Finding so much evidence of life in what is now a relatively barren desert supports the importance of field work, according to the researchers.

 "Here we have an example of the disconnect between theoretical models versus real evidence on the ground," Marks said.

 However, when these artifacts were made, instead of being desolate, Arabia was very wet, with copious rain falling across the peninsula, transforming its barren deserts to fertile, sprawling grasslands with lots of animals to hunt, the researchers explained.

 "For a while, South Arabia became a verdant paradise rich in resources large game, plentiful fresh water, and high-quality flint with which to make stone tools," Rose said.

 Instead of hugging the coast, early modern humans might therefore have spread from Africa into Arabia along river networks that would've acted like today's highways, researchers suggested. There would have been plenty of large game present, such as gazelles, antelopes and ibexes, which would have been appealing to early modern humans used to hunting on the savannas of Africa.

 "The genetic signature that we've seen so far of an exodus 70,000 years ago might not be out of Africa, but out of Arabia," Rose told LiveScience. [Out of Eurasia theory as expressed by other non-PC researchers in the field of anthropology ~ Cailen.]

 So far the researchers have not discovered the remains of humans or any other animals at the site. Could these tools have been made by now-extinct human lineages such as Neanderthals that left Africa before modern humans did? Not likely, Rose said, as all the Nubian Middle Stone Age tools seen in Africa are associated with our ancestors.

 It remains a mystery as to how early modern humans from Africa crossed the Red Sea, since they did not appear to enter the Arabian Peninsula from the north, through the Sinai Peninsula, Rose explained. "Back then, there was no land bridge in the south of Arabia, but the sea level might not have been that low," he said. Archaeologists will have to continue combing the deserts of southern Arabia for more of what the researchers called a "trail of stone breadcrumbs."

 The scientists detailed their findings online Nov. 30 in the journal PLoS ONE.


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