| Author | The Flores Hobbit |
bat400
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|  Posted 23-04-2010 at 04:49
This thread will contain news stories about the Flores "hobbit".
Previous stories on this exciting find can be found at the following links:
'Hobbits' in Indonesia - January 2007
Indonesian 'hobbit' challenges evolutionary theory - 15 Mar 2010
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bat400
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| Posted 23-04-2010 at 04:54
Tools push back dates for humans on Flores - submitted by coldrum.
A new batch of stone tools suggest humans colonised the famous Indonesian 'hobbit' island of Flores much earlier than previously thought, say researchers. Professor Mike Morwood and Dr Adam Brumm of the University of Wollongong and colleagues report their study of the tools today in the journal Nature.
"We're pushing back the antiquity of hominins on Flores," says Morwood. Prior to this study, the oldest stone tools found on Flores were about 880,000 years old. Now in joint research with the Indonesian-Australian research with the Geological Survey Institute of Bandung, Morwood, Brum and colleagues have dated tools around a million years old, pushing the date that humans colonised Flores back by 120,000 years.
The tools came from an entirely new site in the Soa basin, to the east of Liang Bua cave, where the 18,000-year-old 'hobbit', Homo floresiensis was found. The tools, which could only have been made by early humans, were in the very bottom sediment layers of the site, just above the bedrock.
Morwood, Brumm and colleagues used a dating method that measures the amount of argon gas trapped in minerals present in volcanic ash deposits above the stone tools.
Brumm says while the findings are "exciting", they are also "frustrating". The fact these tools are on the bedrock at these sites, mean that any evidence of even earlier human occupation of Flores would not be found there.
"The search is on to try and find other sedimentary basins on Flores that may well have a geological record spanning 1 to 2 million years ago," says Brumm.
He says the ideal situation would be to find skeletal remains of early humans in sediments dating back to the early and middle Pleistocene.
When the hobbit was first discovered, it was thought to be descended from the large-bodied Homo erectus, which had somehow become isolated on Flores and undergone dwarfism. But, says Morwood, subsequent anatomical evidence suggested the hobbit was instead descended from an even more primitive and smaller creature, such as Homo habilis. The presence of such a primitive creature in this part of the globe challenges the generally accepted "Out of Africa" theory and suggests important human evolution may have happened in Asia.
For more, see ABC Science.
[ This message was edited by: bat400 on 2010-04-23 04:55 ]
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bat400
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| Posted 16-10-2010 at 21:09
Researchers offer alternate theory for found skull's asymmetry
Submitted by coldrum ---
A new turn in the debate over explanations for the odd features of LB1 -- the specimen number of the only skull found in Liang Bua Cave on the Indonesian island of Flores and sometimes called "the hobbit" -- is further evidence of a continued streak of misleading science regarding the development of a new species, according to researchers.
Robert Eckhardt, professor of developmental genetics and evolutionary morphology at Penn State, and Maciej Henneberg, Wood Jones professor of anthropological and comparative anatomy at the University of Adelaide, dispute that the skull represents a new species in the Aug. 31 issue of American Journal of Physical Anthropology.
"We have a case in which the majority of workers in paleoanthropology support the idea that a single asymmetrical skull is the representative of a new species rather than an individual abnormal human," said Eckhardt. "Instead, LB1 provides a fantastic example of how biomedical research methods can be used to study the evidence for human developmental patterns whenever and wherever they occur."
What Eckhardt called an "unscientific" dialogue has eclipsed core facts in the debate -- the existing data on LB1's development, he said.
The facts concern left-right asymmetry of LB1's face and braincase. In 2006, Eckhardt and colleagues showed that the face and braincase of LB1 were abnormally asymmetrical.
"Virtually everyone is asymmetrical to a minor degree," he noted. Normal becomes abnormal when that asymmetry exceeds about 1 percent. LB1 surpasses this cutoff for developmental abnormality -- all eight measurements on either side of the facial midline exceed 6 percent asymmetry, most by a large margin. The unusually large differences between the two sides of the skull provided evidence of disordered development, reinforcing their idea that the tiny brain of LB1 signaled not a new species, but a malformed human ancestor.
Over the past three years, a series of papers written by other researchers argued a contrasting opinion -- that the LB1 skull was symmetrical, not malformed.
In 2009 published research by Yousuke Kaifu of the University of Tokyo and his collaborators showed that the skull of LB1 was asymmetrical, as Eckhardt and his colleagues had maintained all along. But Kaifu and his collaborators then proposed the explanation that LB1 suffered from an environmentally caused disease known as posterior deformational plagiocephaly (PDP) -- a skull condition caused by too much pressure put on one part of an infant's head.
In their journal article last month, Eckhardt and Henneberg respond that this diagnosis is impossible.
The first reason, they point out, is that widespread PDP is a relatively modern problem. The 1990s witnessed a large increase in the incidence of PDP because parents began putting infants to sleep on their backs to reduce the risk of sudden infant death syndrome (SIDS). The constant pressure on the back of the skull can cause a permanent deformation, which is PDP.
If LB1 represents a novel species with ancient roots, its ancestors predate PDP, say Eckhardt and Henneberg.
According to Eckhardt, Kaifu noted that PDP became evident only after the development of secondary altriciality, which forced modern humans to deliver a helpless newborn with soft and malleable cranial bones. The primate ancestors of humans probably were less dependent on their mothers than modern human infants. As the size of the neonate skull increased through time, human babies left the womb earlier in development to keep brain function intact.
This shift to more altricial comes much later than the hypothesized evolutionary branch point that led to "Homo floresiensis." LB1's discoverers invented this term to name LB1's species, which they believe to be different than direct human ancestors. Eckhardt and Henneberg disagree with this proposal. There is debate among paleoanthropologists over when hominids evolved to become extremely altricial, but these estimates generally range from about 500,000 to 200,000 years ago.
"No one outside of our research group seems to have recognized this contradiction," said Eckhardt. "With a chimp-sized brain, there is no basis for invoking plagiocephaly to explain the asymmetry seen in LB1."
Eckhardt said that, aside from having a tiny brain, LB1 resembles the normal people who still live on Flores in many features (such as jaws and teeth). But that tiny brain of LB1 is inside an asymmetrical skull, which is powerful independent evidence for abnormal development. He believes that many researchers in the field of paleoanthropology tend to favor differences as evidence of a new species rather than looking at characteristics as reflecting child development.
For more, see http://live.psu.edu/story/48238
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bat400
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| Posted 16-10-2010 at 21:12
'Hobbit' Was an Iodine-Deficient Human, Not Another Species, New Study Suggests.
Submitted by coldrum ---
A new paper is set to re-ignite debate over the origins of so-called Homo floresiensis -- the 'hobbit' that some scientists have claimed as a new species of human.
The University of Western Australia's Emeritus Professor Charles Oxnard and his colleagues, in a paper in PLoS ONE have reconfirmed, on the post-cranial skeleton, their original finding on the skull that Homo floresiensis in fact bears the hallmarks of humans -- Homo sapiens -- affected by hypothyroid cretinism.
The remains, allegedly as recent as 15,000 years, were discovered in 2003 in the Liang Bua caves on the Indonesian island of Flores by archaeologists seeking evidence of the first human migration from Asia to Australia.
When Professor Oxnard and fellow Australian researchers suggested in a 2008 paper that the skull showed evidence of endemic dwarf cretinism resulting from congenital hypothyroidism and were not a new species of human, their claim caused controversy.
In order to test their thesis, in their new paper Professor Oxnard and his team summarised data on the rest of the skeleton and mathematically compared the bones of cretins in relation to chimpanzees, unaffected humans and H. floresiensis. They used two methods with different statistical bases: principal components analyses (PCA) and non-metric multi-dimensional scaling (MDS).
Their work confirms the close grouping of H. floresiensis with the hypothyroid cretins, and the clear separation from both modern humans and from chimpanzees. This leads them to conclude that the Liang Bua remains were indeed most likely cretins from a population of unaffected H. sapiens. They have, further, provided a series of predictions for the further testing of the cretin hypothesis.
"This is consistent with recent hypothyroid endemic cretinism throughout Indonesia, including the nearby island of Bali," Professor Oxnard said.
"Cretinism is caused by various environmental factors including iodine deficiency -- a deficiency which would have been present on Flores at the period to which the dwarfed Flores fossils are dated."
For more, seehttp://www.sciencedaily.com/releases/2010/09/100928025514.htm
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bat400
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| Posted 18-02-2011 at 02:52
Prospects of recovering ancient DNA from Homo floresiensis boosted by study on teeth.
Scientists are planning an attempt to extract DNA from the 'hobbit' Homo floresiensis, the 1-metre-tall extinct distant relative of modern humans that was unearthed in Indonesia, following a study that suggests problems in standard sampling methods in ancient-DNA research could have thwarted previous efforts.
This year, geneticists at the Australian Centre for Ancient DNA (ACAD) at the University of Adelaide hope to recover DNA from a roughly 18,000-year-old H. floresiensis tooth, which was excavated in 2009 from the Liang Bua site on the Indonesian island of Flores.
The premolar has been kept cold, and has been handled as little as possible to prevent contamination with modern DNA. But little, if any, of the ancient DNA is likely to have survived the heat and moisture of the tropics, and any that has may be highly fragmented.
Tony Djubiantono, (Indonesian National Centre for Archaeology, Jakarta,) where the tooth is held, says that developments in DNA extraction techniques could have exciting potential for understanding the evolutionary history of H. floresiensis.
If the DNA can be extracted, comparing its sequence to that of other species could settle disputes over classification.
Five years ago, two teams, one from ACAD and one from the Max Planck Institute of Evolutionary Anthropology in Leipzig, Germany, attempted to recover DNA from another H. floresiensis tooth excavated in 2003. Both attempts failed.
Now, a team led by Christina Adler, a geneticist at ACAD, has found that standard sampling procedures could be responsible for the failure to get DNA from the hobbit and some other ancient specimens.
Adler's team compared the impacts of various sampling techniques on DNA from the mitochondria of 40 human specimens from around the world, which had been dated up to 7,500 years old.
Drilling is a technique commonly used to sample teeth, because it minimizes damage to the precious specimen. But Adler's team found that the heat generated at standard drill speeds (1,000 revolutions per minute) destroys DNA, causing yields to be up to 30 times lower than for samples pulverized in a mill. Reducing the drill speed to 100 RPM alleviated the problem.
Adler says that several ancient specimens that previously failed to yield DNA might now warrant re-sampling. She is surprised that ancient-DNA researchers commonly choose to drill at high speeds for samples, because dentists have long known that this harms their patients' teeth. "This is a case of a lack of communication between two specialist fields that are both working on similar things independently," she says.
Thanks to coldrum for the link. For more, see Cheryl Jones's article at:
http://www.nature.com/news/2011/110105/full/news.2011.702.html.
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bat400
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| Posted 18-01-2013 at 20:56
The Flores Hobbit's face revealed
An Australian anthropologist has used forensic facial reconstruction techniques to show, for the first time, how the mysterious Flores 'hobbit' might have once looked.
Homo floresiensis, as the hobbit is officially known, caused a storm of controversy when it was discovered in Flores, Indonesia in 2003. Some argued the hobbit was an entirely new species, while others suggested it may have simply been a diseased specimen of an existing human species.
Using techniques she has previously applied to help police solve crimes, Honorary Senior Research Fellow at the University of Wollongong and specialist facial anthropologist, Dr Susan Hayes, moulded muscle and fat around a model of the hobbit's skull to flesh out her face. The results show a suprisingly familiar face, with high cheekbones, long ears and a broad nose.
"She's not what you'd call pretty, but she is definitely distinctive," Dr Hayes said in a statement. "She's taken me a bit longer than I'd anticipated, has caused more than a few headaches along the way, but I'm pleased with both the methodological development and the final results."
Darren Curnoe, a human evolution specialist at the University of New South Wales, said the face looked more modern than he expected. He said, "I think it's really interesting to see a new approach founded in forensic science and it can actually progress the ways we can understand what Homo floresiensis looked like. What we have seen, until now, have been artistic interpretations, very beautiful ones, but I think this really takes it to a new level and gives us a more scientific and accurate view of what the hobbit looked like."
Dr Curnoe said that now the majority of researchers accepted that the hobbit was unique and not a diseased human. "But precisely where it fits in the human evolutionary tree is still to be determined."
Thanks to coldrum for the link. Read more at: phys.org/news.
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Andy B
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| Posted 16-08-2013 at 23:05
Professor Mike Morwood, discoverer of the 'Hobbit' fossil bones has died aged 62. Hed a joint Australian-Indonesian team of archaeologists which, in 2003, uncovered what appeared to be the bones of a previously unknown species of human being on the remote Indonesian island of Flores — an event hailed as one of the most sensational findings of modern times.
http://www.telegraph.co.uk/news/obituaries/10200143/Professor-Mike-Morwood.html
Iain Davidson writes: The dating of the find was remarkable, as it seemed to suggest that the Hobbits were in Flores as early as 70,000 years ago – before modern humans were anywhere in the region – and survived as recently as 13,000 years go, long after the arrival of modern humans in Australia and New Guinea more than 50,000 years ago. Yet there were no remains of modern humans, or other evidence of them, in Flores until after the Hobbits became extinct. One of my last conversations with Mike was about the implications of (still unpublished) dating determinations that put the fossils at much earlier dates.
http://www.theguardian.com/science/2013/aug/13/mike-morwood
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Andy B
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| Posted 16-08-2013 at 23:06
Very sad news. The cave where they were discovered is here
Liang Bua Cave
http://www.megalithic.co.uk/article.php?sid=27554
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