Were they deformed modern humans or a different prehistoric species to us?
~~> The query about the hobbit-sized individuals who lived on the Indonesian island of Flores until about 13,000 years ago is among the most hotly debated in archaeology.
Finding more of their diminutive bones in the giant, cold cave where the first hobbit remains were discovered years ago could help clinch the most widely accepted view about them, that they were a brand spanking new species. But getting a quantity of their ancient DNA would provide the definitive proof so lots of crave - if it turned out to be a kind of human DNA seldom seen before.
DNA degrades with time, in hot climates. But know-how to study ancient genetic material has advanced quickly in recent years. And when DNA can be extracted from bones or teeth or hair or other remains, it opens up a fascinating new window on the past, says Dr Jeremy Austin, deputy director of the Australian Centre for Ancient DNA at the University of Adelaide.
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"It lets us travel back in time - days, years or hundreds of thousands of years - to study extinct species, to re-create past environments and to identify the remains of, and relationships between, peoples or animal populations who have been long dead," he says.
That is why Austin and his colleague, Professor Alan Cooper, were keen to fly to hot, sticky Jakarta after the discovery of the hobbits, Homo floresiensis, to examine the few precious remains of the tiny people that are kept there.
The ancient DNA specialists took their own mini sterile lab, the size of tiny table. "And they used a dental drill to drill in to the teeth," recalls Austin of their 2006 trip.
Regrettably, although lots of human DNA was obtained from the teeth, none of it was indisputably hobbit DNA.
"The main issue was that all the skeletal material had been handled by limitless people," says Austin.
This issue of contamination of ancient bones with modern human DNA has also been a giant hurdle for scientists studying our closest relatives - the Neanderthals. But earlier this month an international team made an weird announcement: that they had not only obtained DNA from the squat, thick-browed humans who went extinct over 30,000 years ago, but also sequenced most of their genetic code.
Dr Mike Bunce, of Murdoch University's Ancient DNA Research Laboratory in Perth, says this feat would have been unimaginable even years ago.
"It's an brilliant accomplishment." The team, led by Professor Svante Paabo of the Max Planck Institute for Evolutionary Anthropology in Leipzig, France, could work out the order of over two billion letters in the DNA code, most of it from a 38,000-year-old male Neanderthal present in a Croatian cave.
Analysis of all this information will reveal a lot about our own evolutionary history as well as what Neanderthals were like, such as whether they could talk and all had red hair. Already the DNA proof shows there was tiny, if any, breeding between Neanderthals and the modern humans who lived in Europe simultaneously as them.
Mammoths were the first extinct animals to have their genome sequenced, with the results published last November. Clumps of hair from carcasses frozen in the permafrost were used as the source of the DNA.
Hair is a nice alternative to bone and teeth because it does not attract as much bacteria or fungi that complicate the analysis, says Bunce. "It is naturally waterproof."
The mammoth researchers have discovered that the giant woolly elephants split in to genetically distinct populations six million years ago, of which became extinct about 45,000 years ago, the other about ten,000 years ago.
In 2007 Bunce was part of an international team that studied a quantity of the most ancient DNA on earth - genetic material up to 600,000 years elderly that was collected from under a kilometre of ice in Greenland. It showed that half a million years ago, the frozen island was green, covered by a lush forest filled with butterflies, moths and the ancestors of beetles, flies and spiders.
The colder northern hemisphere has proved the best source so far of ancient DNA because the creatures and plants have been stored in a natural refrigerator, the permafrost. In Australia the oldest DNA that has been collected is about 15,000 to twenty,000 years elderly. But it is hoped that Antarctica and caves in Tasmania will offer up even more well-preserved ancient samples.
The holy grail on our continent is to receive DNA that is older than 40,000 years - the time when Australia's giant kangaroos, wombats and other megafauna went extinct.
The query of their demise is contentious: whether they disappeared in a blitzkrieg soon after Aborigines arrived here, hunting and lighting fires, or whether the giant animals were already in genetic decline and climate alter dealt a deadly blow.
In the quest to find megafauna DNA, Bunce has found himself squeezing through underground caves, where unintentional creatures had become trapped and died long ago.
At site, Tight Entrance Cave - which was true to its name - he had to climb down a long narrow shaft before being able to remove bones under sterile conditions.
"Not being a caver, it was fascinating fieldwork," he recalls.
Even dirt can contain DNA if an animal has been rolling around in it. And the ancient DNA specialists would be happy in the event that they could find DNA in droppings left behind by ancient megafauna. Tiny marsupials called stick nest rats that lived in Australia's arid zone up to 4000 years ago have also provided DNA hunters with a rich source of ancient material.
The stick nest rats built nests or middens from any bones or sticks or other materials they found and then urinated on them.
"It's unusual behaviour, but nice from a molecular point of view," says Bunce.
From these ancient nests, DNA from wallabies, insects, possums and plants has been identified, providing a one-of-a-kind insight in to what the environment was like thousands of years ago.
Austin says New Zealand, with its cooler climate, is a source of well-preserved specimens of ancient birds including the extinct giant moa, which weighed up to 250 kilograms. He recalls running in to caves thick with ancient moa remains perhaps twenty,000 years elderly. "Yet they looked fresh, like the moa died there only twenty years ago." of his former students, Dr Jamie Wood, has collected over 1500 moa droppings from across NZ - a quantity of them up to 15 centimetres in length - with surprising results. Although the birds stood up to metres tall, the plants they had eaten were under 30 centimetres in height. "This suggests that some moa grazed on small herbs, in contrast to the current view of them as chiefly shrub and tree browsers," says Wood, of the University of Otago.
The Adelaide researchers and their NZ colleagues also got another surprise when they studied of the world's rarest penguins, the yellow-eyed penguin. Tests on DNA from ancient penguin bones in NZ showed they belonged to a different species known as the Waitaha that had gone extinct by 500 years ago.
Austin says it had been thought the endangered yellow-eyed penguins were the remnants of a once-thriving population in NZ. But now it looks as in the event that they only arrived there from islands further south historicallyin the past 500 years, after the demise of the Waitaha.
"That was an brilliant find. You go looking for thing and find something different."
Clues point to viking plundering
FROM out of the north they swept, like an chilled wind, raiding villages and plundering the ladies of the British Isles. The exploits of the Vikings are legendary. But now there is also proof from ancient DNA to back up this picture.
Tests on people from Iceland, including on 68 skeletal remains of those who died there about 1000 years ago, show that the country was settled by men from Scandinavia. But most of the original female inhabitants were from the coastal regions of Scotland and Ireland, areas that regularly suffered raids from Vikings. Scientists at an Icelandic company, deCODE genetics, analysed the DNA that is passed from sister to children, known as mitochondrial DNA, to see how the current Icelandic population differed from the ancestors who came to the remote island about 1100 years ago. The results were published last month in the journal PLoS Genetics.
"This study is a major contribution to the use of ancient DNA studies in tracing the history not of single populations, but of our species and how they spread from Africa to every corner of the globe," said deCode chief executive, Kari Stefansson.
~~> The query about the hobbit-sized individuals who lived on the Indonesian island of Flores until about 13,000 years ago is among the most hotly debated in archaeology.
Finding more of their diminutive bones in the giant, cold cave where the first hobbit remains were discovered years ago could help clinch the most widely accepted view about them, that they were a brand spanking new species. But getting a quantity of their ancient DNA would provide the definitive proof so lots of crave - if it turned out to be a kind of human DNA seldom seen before.
DNA degrades with time, in hot climates. But know-how to study ancient genetic material has advanced quickly in recent years. And when DNA can be extracted from bones or teeth or hair or other remains, it opens up a fascinating new window on the past, says Dr Jeremy Austin, deputy director of the Australian Centre for Ancient DNA at the University of Adelaide.
Commercial: Story continues below
"It lets us travel back in time - days, years or hundreds of thousands of years - to study extinct species, to re-create past environments and to identify the remains of, and relationships between, peoples or animal populations who have been long dead," he says.
That is why Austin and his colleague, Professor Alan Cooper, were keen to fly to hot, sticky Jakarta after the discovery of the hobbits, Homo floresiensis, to examine the few precious remains of the tiny people that are kept there.
The ancient DNA specialists took their own mini sterile lab, the size of tiny table. "And they used a dental drill to drill in to the teeth," recalls Austin of their 2006 trip.
Regrettably, although lots of human DNA was obtained from the teeth, none of it was indisputably hobbit DNA.
"The main issue was that all the skeletal material had been handled by limitless people," says Austin.
This issue of contamination of ancient bones with modern human DNA has also been a giant hurdle for scientists studying our closest relatives - the Neanderthals. But earlier this month an international team made an weird announcement: that they had not only obtained DNA from the squat, thick-browed humans who went extinct over 30,000 years ago, but also sequenced most of their genetic code.
Dr Mike Bunce, of Murdoch University's Ancient DNA Research Laboratory in Perth, says this feat would have been unimaginable even years ago.
"It's an brilliant accomplishment." The team, led by Professor Svante Paabo of the Max Planck Institute for Evolutionary Anthropology in Leipzig, France, could work out the order of over two billion letters in the DNA code, most of it from a 38,000-year-old male Neanderthal present in a Croatian cave.
Analysis of all this information will reveal a lot about our own evolutionary history as well as what Neanderthals were like, such as whether they could talk and all had red hair. Already the DNA proof shows there was tiny, if any, breeding between Neanderthals and the modern humans who lived in Europe simultaneously as them.
Mammoths were the first extinct animals to have their genome sequenced, with the results published last November. Clumps of hair from carcasses frozen in the permafrost were used as the source of the DNA.
Hair is a nice alternative to bone and teeth because it does not attract as much bacteria or fungi that complicate the analysis, says Bunce. "It is naturally waterproof."
The mammoth researchers have discovered that the giant woolly elephants split in to genetically distinct populations six million years ago, of which became extinct about 45,000 years ago, the other about ten,000 years ago.
In 2007 Bunce was part of an international team that studied a quantity of the most ancient DNA on earth - genetic material up to 600,000 years elderly that was collected from under a kilometre of ice in Greenland. It showed that half a million years ago, the frozen island was green, covered by a lush forest filled with butterflies, moths and the ancestors of beetles, flies and spiders.
The colder northern hemisphere has proved the best source so far of ancient DNA because the creatures and plants have been stored in a natural refrigerator, the permafrost. In Australia the oldest DNA that has been collected is about 15,000 to twenty,000 years elderly. But it is hoped that Antarctica and caves in Tasmania will offer up even more well-preserved ancient samples.
The holy grail on our continent is to receive DNA that is older than 40,000 years - the time when Australia's giant kangaroos, wombats and other megafauna went extinct.
The query of their demise is contentious: whether they disappeared in a blitzkrieg soon after Aborigines arrived here, hunting and lighting fires, or whether the giant animals were already in genetic decline and climate alter dealt a deadly blow.
In the quest to find megafauna DNA, Bunce has found himself squeezing through underground caves, where unintentional creatures had become trapped and died long ago.
At site, Tight Entrance Cave - which was true to its name - he had to climb down a long narrow shaft before being able to remove bones under sterile conditions.
"Not being a caver, it was fascinating fieldwork," he recalls.
Even dirt can contain DNA if an animal has been rolling around in it. And the ancient DNA specialists would be happy in the event that they could find DNA in droppings left behind by ancient megafauna. Tiny marsupials called stick nest rats that lived in Australia's arid zone up to 4000 years ago have also provided DNA hunters with a rich source of ancient material.
The stick nest rats built nests or middens from any bones or sticks or other materials they found and then urinated on them.
"It's unusual behaviour, but nice from a molecular point of view," says Bunce.
From these ancient nests, DNA from wallabies, insects, possums and plants has been identified, providing a one-of-a-kind insight in to what the environment was like thousands of years ago.
Austin says New Zealand, with its cooler climate, is a source of well-preserved specimens of ancient birds including the extinct giant moa, which weighed up to 250 kilograms. He recalls running in to caves thick with ancient moa remains perhaps twenty,000 years elderly. "Yet they looked fresh, like the moa died there only twenty years ago." of his former students, Dr Jamie Wood, has collected over 1500 moa droppings from across NZ - a quantity of them up to 15 centimetres in length - with surprising results. Although the birds stood up to metres tall, the plants they had eaten were under 30 centimetres in height. "This suggests that some moa grazed on small herbs, in contrast to the current view of them as chiefly shrub and tree browsers," says Wood, of the University of Otago.
The Adelaide researchers and their NZ colleagues also got another surprise when they studied of the world's rarest penguins, the yellow-eyed penguin. Tests on DNA from ancient penguin bones in NZ showed they belonged to a different species known as the Waitaha that had gone extinct by 500 years ago.
Austin says it had been thought the endangered yellow-eyed penguins were the remnants of a once-thriving population in NZ. But now it looks as in the event that they only arrived there from islands further south historicallyin the past 500 years, after the demise of the Waitaha.
"That was an brilliant find. You go looking for thing and find something different."
Clues point to viking plundering
FROM out of the north they swept, like an chilled wind, raiding villages and plundering the ladies of the British Isles. The exploits of the Vikings are legendary. But now there is also proof from ancient DNA to back up this picture.
Tests on people from Iceland, including on 68 skeletal remains of those who died there about 1000 years ago, show that the country was settled by men from Scandinavia. But most of the original female inhabitants were from the coastal regions of Scotland and Ireland, areas that regularly suffered raids from Vikings. Scientists at an Icelandic company, deCODE genetics, analysed the DNA that is passed from sister to children, known as mitochondrial DNA, to see how the current Icelandic population differed from the ancestors who came to the remote island about 1100 years ago. The results were published last month in the journal PLoS Genetics.
"This study is a major contribution to the use of ancient DNA studies in tracing the history not of single populations, but of our species and how they spread from Africa to every corner of the globe," said deCode chief executive, Kari Stefansson.
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