Embargo lifted 11:30am AEST Friday 3 July 2009


New research published in PLoS ONE on Friday describes the remains of three new species of dinosaur: two giant herbivores (sauropods) and a carnivore (theropod) found during digs in the Winton Formation of central Queensland. They are the first large Australian dinosaurs to be discovered since 1981.

Below, several Australian experts in palaeontology respond to the paper. The fossils were unveiled today at the Australian Age of Dinosaurs Museum by the Queensland Premier, Anna Bligh.

To read the paper go to: http://dx.plos.org/10.1371/journal.pone.0006190

Media releases from the Queensland Premier and PLoS One are available here.

Further information on each of the dinosaurs is also available on the Queensland Museum website.

IMAGES: Bone and dinosaur images can be downloaded via the above PLoS link or go to the www.australianageofdinosaurs.com website.

FOOTAGE: Broadcast quality footage taken during a recent visit to the dig site by scientists from La Trobe University is also available. For further info, contact us.

For comments made by the paper’s academic editor at PLoS, click here.

Feel free to use the quotes below in your stories. Any further comments will be posted here. If you would like to speak to an expert, please don’t hesitate to contact us on (08) 8207 7415 or by email.

Dr John Long is a palaeontologist and Head of Sciences at Museum Victoria.

“Wow! This is amazing stuff. I would regard the paper by Scott Hucknull and his team as one of the most significant papers ever published on Australian dinosaurs to date. It not only presents us with two new amazing long-necked giants of the ancient Australian continent, but also announces our first really big predator known from more than scrappy remains – Australovenator. This find also solves an old debate that has been raging since 1981 over Victoria’s ‘Allosaurus’ that is known from a single ankle bone, as it now appears to belong to Australoventor, which shows interesting links to the truly gargantuan group of Gondwana meat-eaters, the carcharodontosauroids.

This paper puts Australia back on the international map of big dinosaur discoveries for the first time since 1981 – when Muttaburrasaurus was announced.”

Associate Professor Rod Wells is from the School of Biological Sciences at Flinders University, SA. Rod is a vertebrate palaeontologist best known for discovering the Naracoorte Caves fossil deposit in SA. He’s an expert in fossil marsupials.

“Mention the word ‘fossil ‘and the immediate response is ‘dinosaur’. Children in particular love their dinosaurs, but when we think of dinosaurs we think North America, Europe, South America, Africa, not Australia. Australia is the exciting new frontier in vertebrate palaeontology, a continent as large as North America awaiting exploration. The dearth of mountain building events on this continent has meant we have no ‘Grand Canyons’ with exposed rock layers spilling fossils; finding fossils in Australia is difficult, time consuming and labour intensive, but the rewards can be outstanding.

Scott Hocknull from the Queensland Museum and his team of volunteers have shown what can be achieved by involving the community in the excitement of scientific discovery. They have opened a new window on the dinosaur fauna of a ~110 million year old portion of the world that remains largely unexplored, indeed a unique Australian fossil heritage. Their work is an exemplar of what can be achieved with limited resources, making an important contribution to basic science, to science education, as well as to the economy of the local community through the Age of Dinosaurs Museum. I applaud their efforts.”

Dr Ben Kear is a palaeontologist based at La Trobe University in Melbourne and an honorary research associate with the SA Museum.

“Australia is one of the great untapped resources in our current understanding of life from the Age of Dinosaurs. The discoveries of Hocknull and colleagues will definitely reinvigorate interest in the hitherto tantalizingly incomplete but globally significant record from this continent and pave the way for new studies on Australian dinosaurs and their environments.”

Dr Tom Rich is Senior Curator (Vertebrate Palaeontology and palaeobotany) at Museum Victoria.

“Where the Winton Formation is commonly exposed, there is a layer of black soil typically about one metre thick. Since at least the 1930s, fossil bones have been found on that surface. However, they were typically isolated bones and often badly broken. Digging in the black soil with hand tools is soul-destroying work. Sort of like digging in a solid mass of rubber. When people did that in the past, little if anything was found in that layer. After finally digging through the black soil and into the underlying sandy clays, the fossil bones found were often disappointing. What Hocknull, the Elliots, and their colleagues have done is to use bulldozers to follow surface traces of bone below the black soil over large areas and then do a lot of digging in the underlying sandy clays. That strategy involved a lot of hard work and expensive machine time. It did not pay off immediately. But it did pay off because they were persistent. They now have demonstrated the appropriateness of a technique that will no doubt reveal much more about the fossil tetrapods of the Winton Formation in the years to come than has been learned before. As the previous record of Australian dinosaurs is so meagre, this heralds a real advance in the years to come.

The three specimens reported by Hocknull and colleagues join less than a dozen others known from this continent from more than a single bone. The theropod is the first occurrence of that group known from anything more than an isolated element. The sauropods show a diversity of titanosaurs in Australia. This group is quite diversified in the Cretaceous of other continents, particularly South America. And it was to be expected that with further discoveries in Australia, this would be found to be the case here. Hocknull and colleagues have found the physical evidence demonstrating that this expectation was in fact correct.

Scott Hocknull was working very closely with David and Judy Elliott of the Australian Age of Dinosaurs Museum in Winton, Queensland. All three of them worked closely together for a number of years to bring off this result. In doing so, they attracted to their project a number of devoted persons who have been critical in their achieving together what they have accomplished.”

Aaron Camens is a PhD research student at the SA Museum and the School of Earth and Environmental Sciences at the University of Adelaide. His main research focus is on fossil marsupials.

“Hocknull and colleagues’ discovery is a fantastic new addition to Australia’s Cretaceous dinosaur record. It also opens a new window into our understanding of dinosaur evolution in the Southern Hemisphere. The Winton Formation is the centre of dinosaurian palaeontology in Australia and Hocknull is right in the thick of it. SA has a grand total of three dinosaur bones, I’m packing my bags for Queensland!”

Scott Hocknull, lead author of the PLos One paper from the Queensland Museum comments on the new carnivorous therapod, nicknamed ‘Banjo’.

“The cheetah of his time, Banjo was light and agile. He could run down most prey with ease over open ground. His most distinguishing feature was three large slashing claws on each hand. Unlike some theropods that have small arms (think T. rex), Banjo was different; his arms were a primary weapon. He’s Australia’s answer to Velociraptor, but many times bigger and more terrifying.

Many hundreds more fossils from this dig await preparation and there is much more material left to excavate.”

Led by palaeontologist Dr Gavin Prideaux of Flinders University in South Australia, it examined the dietary habits of the giant Kangaroo, Procoptodon goliah, and found that the animal would have fed largely on saltbush shrublands. This suggests that landscape burning and changes in the climate are unlikely to have brought about its demise, because saltbush shrublands carry fire poorly and thrive in dry conditions, leaving human hunting as the most likely explanation.

Feel free to use these quotes in your stories. Any further comments will be posted here. If you would like to speak to an expert, please don’t hesitate to contact us on (08) 8207 7415 or by email.

Professor Tim Flannery is Professor of Environmental and Life Sciences at Macquarie University

“This careful, fine-grained study of a single megafaunal species has revealed more about ecology and extinction of Procoptodon goliah than all previous research combined. It’s just the sort of study that promises to give us a definitive answer to the vexed question of what killed off the world’s megafauna. Given our lamentable ignorance of many other megafaunal species, however, for now it must be regarded as just another very solid brick in a strongly building argument that human hunting, rather than climate, was the cause.”

Professor Richard ‘Bert’ Roberts is from the School of Earth and Environmental Sciences, University of Wollongong

“This study neatly ties up several loose threads in the long-running extinction debate. What pushed the Australian megafauna over the edge into oblivion? The weight of evidence is now tipped heavily in favour of hunting by humans. Through detailed reconstructions of the diet of the largest of the now-extinct giant kangaroos that once graced Australia, Gavin Prideaux and colleagues convincingly show that vegetation burning and increased aridity were not the immediate cause of extinction of this ‘whopper hopper’. Their conclusions echo those found late last year for the Tasmanian megafauna, which were also probably extinguished by early human hunters.

By independently reaching the same conclusion for two very different environments – the mountainous rainforests of Tasmania and the dry rangelands of inland Australia – the mystery is no longer whether humans were ultimately responsible for the disappearance of the giant marsupials, but how they did it. As Barry Brook (University of Adelaide) and Chris Johnson (James Cook University) have elegantly demonstrated, it takes only a modest level of hunting of juveniles to drive slow-breeding animals, such as the Australian megafauna, inexorably towards extinction in a few hundred years. So it’s little wonder that direct traces of hunting remain elusive, given the low off-take of animals required to exterminate them and the brief overlap between the first human arrivals on this continent and the last of our magnificent megafauna.”

Professor Chris Johnson is from the School of Marine and Tropical Biology, James Cook University, Qld. He is an expert in and the biology of extinction with a special interest in the biology of Australian marsupials.

“Prideaux and colleagues have done a terrific job of reconstructing the ecology of this giant species of kangaroo, from the few bones and teeth that are all that remain of it. We now know what plants it ate; how it moved and how it fed; that it needed to drink often; but that it was adapted for efficient long-distance travel so could range out far from waterholes and feed on dry open plains. I think they are right that this new understanding rules out fire or climate change as causes of its extinction, and that the real cause was hunting.

But I actually think the main importance of this paper is in helping to show how dramatically the ecology of Australia changed when people first came here. Procoptodon goliah emerges from this study as a specialist kangaroo of saltbush plains. Probably, every other major vegetation type in Australia had its own specialized large herbivores that helped maintain the continent’s ecological balance. With their extinction 45 000 years ago, a great part of the complexity of Australian ecology disappeared. We are only just beginning to comprehend the scale of this loss.”

Dr John Magee is from the Department of Earth and Marine Sciences at the Australian National University

“This study has made a major contribution to elucidating the cause of extinction of the Australian megafauna, a research question that has polarised debate for more than 150 years. Much of that debate has been waged between opposing entrenched positions and has very often consisted of opinion-based arguments. One way out of this impasse is through autecological studies of individual megafaunal species. Autecology is the study of the interactions of a single species with its environment and aims to elucidate the requirements, the life history, and the behavior of the species. With extant animals this can be achieved by experimentation and direct measurement, but is much more difficult with extinct species.

The results obtained by this study provide strong support for the role of humans in the extinction of P. goliah and point to a specific mechanism. But most importantly they follow on from carbon-isotopic palaeodiet studies of the extinct giant flightless bird Genyornis newtoni, by our own research group, in establishing convincing data-based evidence for resolving the likely cause of extinction for an element of the megafauna. Similar autecological studies of other elements of the megafauna are urgently required to fully resolve the megafaunal extinction debate. The results so far challenge those who believe that the extinction is climate driven to find real data to support that argument.”

Dr Judith Field is a Senior Research Associate in Microscopy and Archaeology at the University of Sydney

“I think the most obvious problem with this paper is the giant leap of logic in demonstrating that the Procoptodon was arid adapted and therefore can’t have died out during times of LGM stress, so therefore people were responsible. This is entirely unsubstantiated nonsense. Why can’t these guys present this interesting (dietary) information without entering into the realms of fantasy by attributing a human cause?

My understanding is that there are no Procoptodon remains co-occurring with an archaeological record on the continent. So why are humans suddenly responsible? It is not clear when Procoptodon became extinct and it may well have disappeared long before humans arrived. The fossil record is so sparse that providing good chronologies from well contextualized remains is a priority, we can agree on that much. Though in this work, palaeontologists are short on context and big on using any dates they can find.

There is still no clear picture of the extinction process and certainly no evidence that it was an event around 46,000 years ago.. This is a construct not supported by any data. Most megafauna cannot be placed within 100,000 years of human arrival. Attributing a human cause to the disappearance of Procoptodon is still made in the absence of any supporting evidence. I applaud the detailed work on establishing diet etc for this species but any proposal that humans were involved is made entirely in the absence of any empirical evidence.”

New research has shown vertebrate sex, or internal fertilisation, and live birth are more ancient and more common in the prehistoric animal world than previously thought.

BRIEFING DETAILS:
DATE: Wednesday 25 Feb 2009
START TIME: 11.30am AEDT
DURATION: Approx 30 min
VENUE: Online

Last year Australian scientists discovered the ‘world’s oldest mother’, Materpiscis attenboroughi, a 375 million year old placoderm fish with an embryo inside it. This indicated that sex had occurred, but until now it was not known how these animals actually ‘did the deed’. Now some of the same scientists have shown that more than one type of ancient fish (Incisoscutum and Austrophyllolepis) had structures leading to pelvic claspers, similar to the penis-like structures of modern day sharks. This discovery proves the existence of internal fertilisation, or sex involving copulation, shifting the evolutionary origin of this reproductive mode further back in time.

SPEAKERS:

Dr John Long is Head of Sciences at the Museum Victoria.

Dr Kate Trinajstic is a Research Fellow in palaeontology at Curtin University of Technology in Perth (previously University of Western Australia)

PRESENTATIONS:

Full Briefing (WebEx):
View here

John Long’s Presentation:
View PowerPoint (pdf) | Listen (mp3)

Kate Trinajstic’s Presentation:
View PowerPoint (pdf) | Listen (mp3)

Q & A Session:
Listen (mp3)

Illustration by ExhibitEase LLC - Steven W. Marcus

After thousands of years of extinction, the woolly mammoth has its DNA decoded this week in Nature. The study marks the first report of nuclear genome sequencing for an extinct animal. Using DNA extracted from samples of hair, the authors were able to collect together the near-complete nuclear genome of the woolly mammoth.

The team used samples from several different mammoth species found preserved in the permafrost to piece together the jigsaw puzzle. Although there are still pieces missing, the authors believe that the sequence of the woolly mammoth is around 80% complete. The findings identify genes shared with its modern elephant cousins, and offer insight into elephantid evolution. Here Australian experts comment on the importance of this research and look at whether we could soon resurrect the mammoth.

Feel free to use these quotes in your stories. If you would like to speak to an expert, please don’t hesitate to contact us on (08) 7120 8666 or by email.

———-

Dr Michael Bunce is Head of the Ancient DNA Laboratory at Murdoch University, Western Australia

“The field of ancient DNA has come a long way since the first study in 1984 which obtained a tiny fragment of DNA from an extinct species called the quagga, a zebra-like – 25 years later scientists are now putting the finishing touches on the first genome of an extinct species; the Woolly Mammoth.

The Mammoth together with the Dodo and Neanderthals are iconic examples of extinctions that have long fascinated human culture. The completion of the first draft genome is a significant accomplishment that is soon be ‘trumped’ by the completion of the Neanderthal genome.

Sequencing 4 billion bases of DNA is a huge undertaking and is made possible by a new generation of DNA sequencing equipment that breaks up the DNA into small pieces then randomly determines the DNA code, a technique called ‘shotgun’ sequencing.

The important scientific contributions that whole genome studies make is through comparisons of the DNA sequences with other species, here the researchers have compared the DNA to that of the African Elephant and to the human genome. By comparing the differences between genomes we can start to answer one of the most fundamental questions about genetics – what gene(s) are responsible for what physical characteristics? For example compared to their African cousins what genes ‘altered’ to make Mammoth better adapted to the cold environment?

Does this genome sequence mean that in a few years we can bring back the mammoth? – far from it. Just because we know the DNA code of something does not mean we can genetically tinker with it to the extent required to recreate extinct organisms – this kind of progress is still a pipe-dream.”

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Dr Jeremy Austin is the Deputy Director of the Australian Centre for Ancient DNA at The University of Adelaide

“This study on mammoth genome sequencing is an important step forward for ancient DNA research. It clearly demonstrates that partial (and possibly complete) genomes can be obtained from extinct species to provide new information on evolution. This is very exciting for a number of reasons. Evolutionary biologists may now be able to ‘see’ evolution of genes under selection in real time by accessing genetic information from historical and ancient samples. Evolutionary biologists will also have a much larger suite of genetic markers to understand the process of molecular evolution and species response to environmental change. However, there are a number of caveats associated with this study. Firstly, mammoths are probably the best preserved extinct animals from which to obtain ancient DNA. The samples used in this study have been preserved in permafrost (essentially a natural deep freeze) for the last 20,000 years. Remains of most extinct animals are not nearly as well preserved and DNA survival in the majority of extinct species will not be as good as in mammoths. Secondly, they only obtained a partial genome. They did not recover the complete genome of a mammoth, despite sequencing two different mammoth specimens. Thirdly, despite the exceptional preservation of the specimens and use of hair for obtaining DNA fully 20% of the sequence obtained appears to be contamination from bacteria or other sources. Fourthly, the authors acknowledge that the mammoth sequences obtained contain errors, approximately 1.5 incorrect bases for every 1000 base pairs of actual sequence. This may not seem much to most people but we already know that many fatal genetic disorders are single point mutations (i.e. one wrong base in a gene). Thus the current mammoth genome may contain up to 6 million ‘incorrect’ base reads (if my quick maths is correct!).

Can we bring a mammoth back to life? As for the much touted thylacine cloning project, the answer is still no for the reasons outlined above. A genome sequence does not make a living organism. Currently we only have a partial mammoth genome, with a sizeable number of errors in the genetic code. It’s a bit like trying to build a car with only 80% of the parts and knowing that some of the parts are already broken. Even if we did have the genome in its entirety we still have the problem of knowing what is a real mutation versus what is sequencing error or DNA damage. At a genome scale this in itself is an almost insurmountable problem. After this we have the issues of how to construct artificial chromosomes, how much epigenetics is involved and many other cell and tissue culture hurdles.”

Australian research sheds new light on the role that our ancestors played in the extinction of Australia’s large prehistoric animals. There has been ongoing debate about whether climate change or human arrival was the major cause of the demise of Australia’s megafauna. On the Australian mainland, 90% of these animals became extinct soon after the first evidence of the arrival of humans, around 46 thousand years ago. Yet on Tasmania, their extinction is thought to have taken place before the arrival of humans, making climate change the most likely culprit.

A new study, published in the journal Proceedings of the National Academy of Sciences of the USA, provides the first evidence that Tasmania’s large prehistoric animals were still roaming the island when humans first arrived. The findings suggest that their mass extinction was the result of human hunting, and not climate change-as previously believed. Here, Australian experts comment on these new findings.

ONLINE BRIEFING | RAPID ROUNDUP

BRIEFING DETAILS:
DATE: Monday 11 August 2008
START TIME: 10.30am AEST
DURATION: 30 minutes
VENUE: Online

SPEAKERS:

Professor Tim Flannery – Earth and Life Sciences at Macquarie University

Professor Richard ‘Bert’ Roberts – Earth and Environmental Sciences, University of Wollongong

Craig Reid - Queen Victoria Museum and Art Gallery in Launceston

PRESENTATIONS:

Full Briefing (WebEx):
View here

Tim Flannery’s Presentation:
Listen (mp3)

Richard Robert’s Presentation:
View PowerPoint (pdf) | Listen (mp3)

Craig Reid’s Presentation:
View PowerPoint (pdf) | Listen (mp3)

Q & A Session:
Listen (mp3)

RAPID ROUNDUP

Feel free to use these quotes in your stories. Any further comments will be posted here. If you would like to speak to an expert, please don’t hesitate to contact us on (08) 8207 7415 or by email.

Professor Barry Brook is Sir Hubert Wilkins Professor of Climate Change and Director, Research Institute for Climate Change and Sustainability at the University of Adelaide

“This latest study of the persistence dates of Australian megafauna reinforces the maturing view in the science community that the ancient extinction of large mammals were consistently coincident with human arrival. Indeed, each apparently discrepancy, which has seemingly showed a long-term co-existence between prehistoric people and large-bodied mammals, are one-by-one being swept aside, thanks to new dating methods and improved site-profiling. The picture is becoming clear. Whodunnit? Wedunnit.”

Professor Christopher Johnson, Ecologist, School of Tropical Biology, James Cook University. He published a book on mammal extinctions in Australia, called “Australia’s Mammal Extinctions: a 50,000 Year History” in 2006.

“This is a big step towards resolution of a very long argument. The evidence that humans caused the extinction of giant ice age mammals in Australia, by over-hunting them, is now much stronger. This study shows that alternative explanations (to do with climate change or fire) won’t work in Tasmania. On the other hand, the big picture that is now much clearer is that when people arrive, other big animals disappear. This is a sad and, it seems, almost inevitable feature of our species’ impact on nature.”

Dr Richard Cosgrove is a Reader in Archaeology in the Archaeology Program at La Trobe University

“This paper suffers from a number of problems, particularly that there is no temporal overlap, and therefore human involvement in megafauna extinction cannot be unequivocally demonstrated from the data presented in the paper. Turney et al’s argument relies on supposition and assumptions about the timing of human entry across the land bridge, is weakened by small sample sizes, including only one species that actually dates to anywhere near the earliest evidence for human occupation and suggests that the archaeological evidence is too weak to detect human megafaunal hunting. There is the selective use of data in the paper, and as it stands, does not address the over-whelming archaeological evidence that preserves one of the best and most detailed late Pleistocene faunal records associated with human hunting anywhere in the world and to ignore this detracts from the very question of human environmental impacts the paper struggles to address. To ignore the archaeological evidence continues to push the ‘faith’ based human extinction argument of palaeontologists and geochronologists where no direct evidence exists.”

Dr Richard Gillespie is a radiocarbon dating specialist and Visiting Fellow at the University of Wollongong and the Australian National University.

“Did the Australian megafauna (giant marsupials, birds and reptiles) become extinct before or after humans first arrived in Tasmania? New results suggest the answer is after. Geological evidence of sea level change shows that a landbridge emerged between mainland Australia and Tasmania about 43,000 years ago, and people must have walked across pretty soon after it became possible because the oldest archaeological sites in Tasmania date to 40,000 years ago.

Archaeologists have found no extinct animal remains among the many thousands of bones excavated from occupation sites, arguing the giant fauna must have been extinct before people got to Tasmania. Turney and colleagues refute that theory with the first reliable radiocarbon dates on any of the Australian megafauna, showing that an extinct giant kangaroo (Protemnodon anak) lived at Mt Cripps in north western Tasmania 41,000 years ago. More dates are needed to confirm these results, which imply that people and extinct megafauna did coexist in Tasmania, if only briefly.

On mainland Australia, hunting by the first human arrivals most likely caused the megafauna extinction about 45,000 years ago, as they did in America 13,000 years ago, Madagascar 2000 years ago, and New Zealand 600 years ago. The only common factor in the global megafauna extinction pattern is that humans first turned up in those places just before the extinctions happened. Supporters of the rival theory, that climate change killed off the megafauna, have run out of places to hide.”

Dr Judith Field is a Senior Research Associate in Microscopy and Archaeology at the University of Sydney.

“Investigations into the timing and cause of the megafaunal extinctions in Australia is hampered by the small datasets with which to evaluate the fossil record. This report attempts to improve our understanding of the timing of the extinction in Tasmania by directly dating a number of specimens, mostly from museum collections and also dating sediments from some cave sites. The authors assert in this paper that humans were involved in the demise and extinction of the Tasmanian megafauna, a belief based on a set of unproven assumptions and radiocarbon dates from one species.

Significantly for this site (and all of the sites they analyse), the all important evidence of a human presence is absent. A short temporal overlap of all Tasmanian megafauna with humans is proposed on the basis of this result and the unproven assumption that OSL dates from sediments in another site, actually date the fauna. This is extrapolated into ‘human involvement in the megafaunal extinctions’. The dismissal of the archaeology based on there being only 0.6% of faunal material in this time period (and without megafauna), neglects to cite that there are over 800,000 bones that have been examined from the Tasmanian archaeological sites.

Their interpretations and discussion are hampered by the belief that they don’t require contextual data – that dates are all they need. Furthermore their inconsistent use of (a dubious) criterion they propose elsewhere as demonstrating in situ assemblages of bones (i.e. articulated skeletons), undermines this case and the case they make for the Australian mainland. To believe that in the absence of any comparative data or supporting evidence that this new report solves the mystery of why megafauna disappeared in Tasmania grossly overstates their case and extends their interpretation into the realms of speculative fantasy. Whether arguing for human or climatic influences as primary agents in megafaunal extinction, researchers must place their results into some sort of site context and demonstrate associations or interactions of megafauna and humans with empirical evidence. Until or unless this happens it remains premature to claim a human role in the demise of the Australian megafauna, especially when humans cannot even be placed at the scene!”

Gavin Prideaux is a palaeontologist and Australian Research Fellow in the School of Biological Sciences at Flinders University

“Tasmania has been a bit of a ‘fly in the ointment’ for those who have argued that Australia’s giant mammals were driven to extinction by humans. The small amount of available evidence seemed to suggest the megafauna disappeared well before people reached the island. Turney and colleagues now show that at least one, and possibly as many as seven species did in fact survive until humans arrival.”