The water, isolated in pockets deep underground for billions of years, is now pouring out of boreholes from a mine 2.4 kilometres (1.5 miles) beneath Ontario, Canada, they wrote in the journal Nature.

"This water could be some of the oldest on the planet and may even contain life," the team said in a statement.

Not only that -- the similarity between the rocks that trapped the fluid and those found on Mars raised hopes that similar life-sustaining water could be buried deep inside the Red Planet, they said.

"The findings... may force us to rethink which parts of our planet are fit for life," they added.

The British and Canadian researchers analysed the water and found it was rich in dissolved gases like hydrogen and methane that are able to sustain microscopic life not exposed to the sun for billions of years, as is the case on the ocean floor.

The rocks around the water were dated about 2.7 billion years old, "but no one thought the water could be the same age, until now," the team said.

Analysing the water's composition in the lab, the team estimated that it was at least 1.5 billion years old, possibly more.

"Our finding is of huge interest to researchers who want to understand how microbes evolve in isolation, and is central to the whole question of the origin of life, the sustainability of life, and life in extreme environments and on other planets," said Manchester University researcher and study co-author Chris Ballentine.

Before this discovery, the only other water from this age had been found trapped in tiny bubbles in rock, incapable of supporting life.

The Canadian water has characteristics similar to much younger water flowing from a mine 2.8 kilometres below ground in South Africa, which is known to support microbes.

"Our Canadian colleagues are trying to find out if the (Ontario) water contains life," said lead author Greg Holland of Lancaster University.

"What we can be sure of is that we have identified a way in which planets can create and preserve an environment friendly to microbial life for billions of years.

"This is regardless of how inhospitable the surface might be, opening up the possibility of similar environments in the subsurface of Mars."

]]> Sat, 18 MAY 2013 00:32:39 AEST College Station TX (SPX) May 15, 2013 - The tiniest bones in the human body - the bones of the middle ear - could provide huge clues about our evolution and the development of modern-day humans, according to a study by a team of researchers that include a Texas A and M University anthropologist.

Darryl de Ruiter, a professor in the Department of Anthropology at Texas A and M, and colleagues from Binghamton University (the State University of New York) and researchers from Spain and Italy have published their work in the current issue of PNAS (Proceedings of the National Academy of Science).

The team examined the skull of a hominin believed to be about 1.9 million years old and found in a cave called Swartkrans, in South Africa. Of particular interest to the team were bones found in the middle ear, especially one called the malleus.

It and the other ear bones - the incus and the stapes - together show a mixture of ape-like and human-like features, and represent the first time all three bones have been found together in one skull.

The malleus appears to be very human-like, the findings show, while the incus and stapes resemble those of a more chimpanzee-like, or ape-like creature. Since both modern humans and our early ancestors share this human-like malleus, the changes in this bone must have occurred very early in our evolutionary history.

"The discovery is important for two reasons," de Ruiter explains.

"First, ear ossicles are fully formed and adult-sized at birth, and they do not undergo any type of anatomical change in an individual lifetime. Thus, they are a very close representation of genetic expression.

Second, these bones show that their hearing ability was different from that of humans - not necessarily better or worse, but certainly different.

"They are among the rarest of fossils that can be recovered," de Ruiter adds.

"Bipedalism (walking on two feet) and a reduction in the size of the canine teeth have long been held to be 'hallmarks of humanity' since they seem to be present in the earliest human fossils recovered to date. Our study suggests that the list may need to be updated to include changes in the malleus as well."

de Ruiter recently authored a series of papers in Science magazine that demonstrate the intermediate nature of the closely related species, Australopithecus sediba, and provide strong support that this species lies rather close to the ancestry of Homo sapiens. The current study could yield additional new clues to human development and answer key questions of the evolution of the human lineage.

]]> Sat, 18 MAY 2013 00:32:39 AEST Toronto (UPI) May 7, 2013 - Paleontologists have named a new species of "bone-headed" dinosaur from Canada, so called for a domed skull above its eyes that was almost 2 inches thick.

Two fossil specimens of the diminutive dinosaur dubbed Acrotholus audeti, from a class of dinosaurs called pachycephalosaur for their distinctive skulls, have been found in Alberta, the scientists said.

At just 6 feet long, including a long tail, and weighing only about 90 pounds, the newly identified plant-eating dinosaur represents the oldest bone-headed dinosaur in North America, and possibly the world, they said.

The first fossil specimen was discovered almost 50 years ago but a much better example was found in 2008 during a field expedition organized by the Royal Ontario Museum and University of Toronto, and the Cleveland Museum of Natural History.

Research describing the new species was published Tuesday in the journal Nature Communications.

"Acrotholus provides a wealth of new information on the evolution of bone-headed dinosaurs," Royal Ontario Museum paleontologist David Evans said. "Although it is one of the earliest known members this group, its thickened skull dome is surprisingly well-developed for its geological age."

Acrotholus lived about 85 million years ago.

"More importantly, the unique fossil record of these animals suggests that we are only beginning to understand the diversity of small-bodied plant-eating dinosaurs," Evans said.

]]> Sat, 18 MAY 2013 00:32:39 AEST Seattle WA (SPX) May 03, 2013 - Many scientists have thought that dinosaur predecessors missed the race to fill habitats emptied when nine out of 10 species disappeared during the Earth's largest mass extinction, approximately 252 million years ago. The thinking was based on fossil records from sites in South Africa and southwest Russia.

It turns out that scientists may have been looking for the starting line in the wrong places. Newly discovered fossils from 10 million years after the mass extinction reveal a lineage of animals thought to have led to dinosaurs taking hold in Tanzania and Zambia in the mid-Triassic period, many millions of years before dinosaur relatives were seen in the fossil record elsewhere on Earth.

"The fossil record from the Karoo of South Africa remains a good representation of four-legged land animals across southern Pangea before the extinction event. But after the event animals weren't as uniformly and widely distributed as before.

"We had to go looking in some fairly unorthodox places," said Christian Sidor, University of Washington professor of biology. He's lead author of a paper appearing the week of April 29 in the early edition of the Proceedings of the National Academy of Sciences.

The new insights come from seven fossil-hunting expeditions since 2003 in Tanzania, Zambia and Antarctica, funded by the National Geographic Society and National Science Foundation, along with work combing through existing fossil collections. The researchers created two "snapshots" of four legged-animals about 5 million years before and again about 10 million years after the extinction event at the end of the Permian period.

Prior to the extinction event, for example, the pig-sized Dicynodon - said to resemble a fat lizard with a short tail and turtle's head - was a dominant plant-eating species across southern Pangea. Pangea is the name given to the landmass when all the world's continents were joined together.

Southern Pangea was made up of what is today Africa, South America, Antarctica, Australia and India. After the mass extinction at the end of the Permian, Dicynodon disappeared and other related species were so greatly decreased that newly emerging herbivores could suddenly compete with them.

"Groups that did well before the extinction didn't necessarily do well afterward," said Sidor, who also is the curator of vertebrate paleontology at the UW's Burkey Museaum of Natural History and Culture. "What we call evolutionary incumbency was fundamentally reset."

The snapshot 10 million years after the extinction event reveals, among other things, that archosaurs were in Tanzanian and Zambian basins, but not distributed across all of southern Pangea as had been the pattern for four-legged animals prior to the extinction.

Archosaurs are the group of reptiles that includes crocodiles, dinosaurs, birds and a variety of extinct forms. They are of interest because it is thought they led to animals like Asilisaurus, a dinosaur-like animal, and Nyasasaurus parringtoni, a dog-sized creature with a five-foot tail that scientists in December 2012 announced could be the earliest dinosaur, or else the closest relative found so far.

"Early archosaurs being found mainly in Tanzania is an example of how fragmented communities became after the extinction event," Sidor said. And the co-authors write: "These findings suggest that . . . archosaur diversification was more intimately related to recovery from the end-Permian mass extinction than previously suspected."

A new framework for analyzing biogeographic patterns from species distributions, developed by co-author Daril Vilhena, a UW biology graduate student, provided a way to discern the complex recovery, Sidor said.

It revealed that before the extinction event 35 percent of four-legged species were found in two or more of the five areas studied, with some species having ranges that stretched 1,600 miles (2,600 kilometers), encompassing the Tanzanian and South African basins. Ten million years after the extinction event, the authors say there was clear geographic clustering and just 7 percent of species were found in two or more regions.

The techniques - new ways to statistically consider how connected or isolated species are from each other - could be useful for other paleontologists and modern day biogeographers, Sidor said.

In the early 2000s Sidor and some of his co-authors started putting together expeditions to collect fossils from sites in Tanzania that hadn't been visited since the 1960s and in Zambia where there'd been little work since the '80s. Two expeditions to Antarctica provided additional materials, as did long-term efforts to examine museum-held fossils that had not been fully documented or named.

Other co-authors from the UW are graduate students Adam Huttenlocker and Brandon Peecook, post-doctoral researcher Sterling Nesbitt and research associate Linda Tsuji; Kenneth Angielczyk of the Field Museum of Natural History in Chicago; Roger Smith, of the Iziko South African Museum in Cape Town; and Sebastien Steyer from the National Museum of Natural History in Paris.

]]> Sat, 18 MAY 2013 00:32:39 AEST Sydney (AFP) May 7, 2013 - Gigantic animals which once roamed Australia were mostly extinct by the time humans arrived, according to a new study Tuesday which suggests climate change played the key role in their demise.

For decades, debate has centred on what wiped out megafauna such as the rhinoceros-sized, wombat-like Diprotodon, the largest known lizard, and kangaroos so big that scientists are studying whether they could hop.

The study, published in the Proceedings of the National Academy of Sciences, said some species were still surviving when people arrived about 45,000 to 50,000 years ago.

But the review, led by the University of New South Wales, found that while human involvement in the disappearance of the megafauna was possible, climate change was the more likely culprit.

"There is no firm evidence whatsoever that a single human ever killed a single individual megafauna," the study's lead author, University of New South Wales zoologist Stephen Wroe told AFP.

"Not a thing. There is not a single kill site in Australia or (Papua) New Guinea. There's not even the sort of tool kit that you would typically associate for hunter gatherers with killing big animals."

Wroe said the fossil records showed that the clear majority of now extinct species of megafauna "can't be placed within even 50,000 years of when humans were thought to have first arrived".

"No more than about 14, perhaps as few as eight, species were clearly here when humans made foot-fall," he said.

Wroe said there was also mounting evidence that their extinction took place over tens, if not hundreds, of millennia during which time there was a progressive deterioration in the climate.

"There is clear evidence that the climate was changing over a long period of time and becoming progressively more extreme," he said, adding this could have been harsh enough to kill off the giant animals, many of which were herbivores.

Some 90 giant animal species once inhabited Australia and Papua New Guinea -- including Diprotodons weighing close to three tonnes and kangaroos weighing up to 300 kilograms -- but their massive size did not ensure their survival.

"You think you've got these big hairy, often fierce beasts and they'll be able to look after themselves, but the cruel irony is that the biggest and fiercest... can be extremely vulnerable," Wroe said.

]]> Sat, 18 MAY 2013 00:32:39 AEST Cape Cod MA (SPX) May 07, 2013 - When Woods Hole Oceanographic Institution (WHOI) marine paleoecologist Marco Coolen was mining through vast amounts of genetic data from the Black Sea sediment record, he was amazed about the variety of past plankton species that left behind their genetic makeup (i.e., the plankton paleome).

The semi-isolated Black Sea is highly sensitive to climate driven environmental changes, and the underlying sediments represent high-resolution archives of past continental climate and concurrent hydrologic changes in the basin. The brackish Black Sea is currently receiving salty Mediterranean waters via the narrow Strait of Bosphorus as well as freshwater from rivers and via precipitation.

"However, during glacial sea level lowstands, the marine connection was hindered, and the Black Sea functioned as a giant lake," says WHOI geologist Liviu Giosan.

He added that "the dynamics of the environmental changes from the Late Glacial into the Holocene (last 10,000 years) remain a matter of debate, and information on how these changes affected the plankton ecology of the Black Sea is sparse."

Using a combination of advanced ancient DNA techniques and tools to reconstruct the past climate, Coolen, Giosan, and their colleagues have determined how communities of plankton have responded to changes in climate and the influence of humans over the last 11,400 years. Their results will be published in the Proceedings of the National Academy of Sciences, USA (PNAS), and will be available online on May 6.

Researchers traditionally reconstruct the make up of plankton by using a microscope to count the fossil skeletons found in sediment cores. But, this method is limited because most plankton leave no fossils, so instead Coolen looked for sedimentary genomic remains of the past inhabitants of the Black Sea water column.

"DNA offers the best opportunity to learn the past ecology of the Black Sea," says Coolen. "For example, calcareous and organic-walled dinocysts are frequently used to reconstruct past environmental conditions, but 90 percent of the dinoflagellate species do not produce such diagnostic resting stages, yet their DNA remains in the fossil record."

However, ancient DNA signatures in marine sediments have thus far been used for targeted reconstruction of specific plankton groups and those studies were based on very small clone libraries. Instead, the researchers used a high throughput next generation DNA sequencing approach called pyrosequencing to look for the overall plankton changes in the Back Sea from the deglaciation to recent times.

In addition, the researchers reconstructed past changes in salinity and temperature as the possible causes for plankton community shifts in the Black Sea.

To reconstruct the salinity, the WHOI team analyzed sediments containing highly resistant organic compounds called alkenones, which are uniquely produced by Emiliania huxleyi-the same photosynthetic organism oceanographers study to determine past sea surface temperatures. By examining the ratio of two hydrogen isotopes in the alkenones, they were able to map the salinity trend in the Black Sea over the last 6,500 years.

"One of the isotopes, deuterium, is not very common in nature," explains Coolen, "And it doesn't evaporate as easily as other isotopes. Higher ratios of deuterium are indicative of higher salinity."

The WHOI team was funded through the National Science Foundation and they collaborated with Chris Quince and his postdoc Keith Harris from the Computational Microbial Genomics Group at the University of Glasgow, and with micropaloentologist Mariana Filipova-Marinova from the Natural History Museum in Varna, Bulgaria.

Their study revealed that 150 of 2,710 identified plankton showed a statistically significantly response to four environmental stages since the deglacial. Freshwater green algae were the best indicator species for lake conditions more than 9,000 years ago although the co-presence of previously unidentified marine plankton species indicated that the Black Sea might have been influenced to some extent by the Mediterranean Sea over at least the past 9,600 years.

Dinoflagellates, cercozoa, eustigmatophytes, and haptophyte algae responded most dramatically to the gradual increase in salinity after the latest marine reconnection and during the warm and moist mid-Holocene climatic optimum. Salinity increased rapidly with the onset of the dry Subboreal climate stage after ca. 5200 years ago leading to an increase in marine fungi and the first occurrence of marine copepods.

A gradual succession of phytoplankton such as dinoflagellates, diatoms, and golden algae occurred during refreshening of the Black Sea with the onset of the cool and wet Subatlantic climate around 2500 years ago. The most drastic changes in plankton occurred over the last century associated with recent human disturbances in the region.

The new findings show how sensitive marine ecosystems are to climate and human impact. The high throughput sequencing of ancient DNA signatures allows us to reconstruct a large part of ancient oceanic life including organisms that are not preserved as fossils.

Coolen added that ancient plankton DNA was even preserved in the oldest analyzed Black Sea lake sediments when the entire water column was most likely well mixed and oxygenated. This means that ancient plankton DNA might be widely preserved in sediments and can likely be used to reconstruct past life in the majority of oceanic and lake environments.

]]> Sat, 18 MAY 2013 00:32:39 AEST Oxford UK (SPX) May 03, 2013 - Tiny 1,900 million-year-old fossils from rocks around Lake Superior, Canada, give the first ever snapshot of organisms eating each other and suggest what the ancient Earth would have smelled like.

The fossils, preserved in Gunflint chert, capture ancient microbes in the act of feasting on a cyanobacterium-like fossil called Gunflintia - with the perforated sheaths of Gunflintia being the discarded leftovers of this early meal.

A team, led by Dr David Wacey of the University of Western Australia and Bergen University, Norway, and Professor Martin Brasier of Oxford University, reports in this week's Proceedings of the National Academy of Sciences the fossil evidence for how this type of feeding on organic matter - called 'heterotrophy' - was taking place.

They also show that the ancient microbes appeared to prefer to snack on Gunflintia as a 'tasty morsel' in preference to another bacterium (Huroniospora).

'What we call 'heterotrophy' is the same thing we do after dinner as the bacteria in our gut break down organic matter,' said Professor Martin Brasier of Oxford University's Department of Earth Sciences, an author of the paper.

'Whilst there is chemical evidence suggesting that this mode of feeding dates back 3,500 million years, in this study for the first time we identify how it was happening and 'who was eating who'.

In fact we've all experienced modern bacteria feeding in this way as that's where that 'rotten egg' whiff of hydrogen sulfide comes from in a blocked drain. So, rather surprisingly, we can say that life on earth 1,900 million years ago would have smelled a lot like rotten eggs.'

The team analysed the microscopic fossils, ranging from about 3-15 microns in diameter, using a battery of new techniques and found that one species - a tubular form thought to be the outer sheath of Gunflintia - was more perforated after death than other kinds, consistent with them having been eaten by bacteria.

In some places many of the tiny fossils had been partially or entirely replaced with iron sulfide ('fool's gold') a waste product of heterotrophic sulfate-reducing bacteria that is also a highly visible marker.

The team also found that these Gunflintia fossils carried clusters of even smaller (c.1 micron) spherical and rod-shaped bacteria that were seemingly in the process of consuming their hosts.

Dr Wacey said that: 'recent geochemical analyses have shown that the sulfur-based activities of bacteria can likely be traced back to 3,500 million years or so - a finding reported by our group in Nature Geoscience in 2011.

Whilst the Gunflint fossils are only about half as old, they confirm that such bacteria were indeed flourishing by 1,900 million years ago. And that they were also highly particular about what they chose to eat.'

]]> Sat, 18 MAY 2013 00:32:39 AEST Vancouver, Canada (SPX) May 03, 2013 - Deposits left by the eruption of a subglacial volcano, or tuya, 1.8 million years ago could hold the secret to more accurate palaeo-glacial and climate models, according to new research by University of British Columbia geoscientists.

The detailed mapping and sampling of the partially eroded Kima' Kho tuya in northern British Columbia, Canada shows that the ancient regional ice sheet through which the volcano erupted was twice as thick as previously estimated.

Subglacial eruptions generate distinctive deposits indicating whether they were deposited below or above the waterline of the englacial lakes--much like the rings left on the inside of a bath tub.

The transitions from subaqueous from subaerial deposits are called passage zones and define the high stands of englacial lakes. The depth and volume of water in these ephemeral lakes, in turn, gives researchers an accurate measure of the minimum palaeo-ice thicknesses at the time of eruption.

"At Kima'Kho, we were able to map a passage zone in pyroclastic deposits left by the earliest explosive phase of eruption, allowing for more accurate forensic recovery of paleo-lake levels through time and better estimates of paleo-ice thicknesses," says UBC volcanologist James K Russell, lead author on the paper published this week in Nature Communications.

"Applying the same technique to other subglacial volcanos will provide new constraints on paleoclimate models that consider the extents and timing of planetary glaciations."

While relatively rare globally, tuyas are common throughout Iceland, British Columbia, Oregon, and beneath the Antarctic ice-sheets. Kima'Kho tuya forms a high relief structure covering 28 square kilometres rising 1,946 metres above sea level on the Kawdy Plateau near Dease Lake. The plateau hosts six other tuyas.

"We hope our discovery encourages more researchers to seek out pyroclastic passage zones," says Lucy Porritt, a Marie Curie Research Fellow at UBC and University of Bristol.

"With more detailed mapping of glaciovolcanic sequences, and the recognition of the importance of these often abrupt changes in depositional environment, our understanding of glaciovolcanic eruptions and the hazards they pose can only be advanced."

]]> Sat, 18 MAY 2013 00:32:39 AEST Kansas City MO (SPX) May 06, 2013 - There's a new actor on the embryology stage: the starlet sea anemone Nematostella vectensis. Its career is being launched in part by Stowers Institute for Medical Research Associate Investigator Matt Gibson, Ph.D., who is giving it equal billing with what has been his laboratory's leading player, the fruit fly Drosophila melanogaster.

Gibson's lab investigates the cellular and molecular mechanisms used by cells to assemble into layers or clusters during embryogenesis. Those tissues, comprised of densely packed cells known as epithelial cells, shape the body not only of simple creatures but also of mammals, where they line every body cavity from lung to intestine and form hormone- and milk-secreting glands. Unfortunately these cells have a dark side too- over 80% of human cancers, carcinomas, are of epithelial origin.

The Gibson lab has historically used the genetic powerhouse Drosophila to investigate the control of epithelial cell shape and proliferation during wing, leg and eye development. Breaking with tradition, their new study published in the May 15th, 2013 issue of Development, explains how developing sea anemone larvae construct an even more basic epithelial appendage, the tentacle.

The paper charts how epithelial cell shape changes drive tentacle development and is also the first to identify candidate genes driving those changes. Most of all, by putting a new model organism representing one of the simplest animals center stage, the study illuminates some of the most fundamental principles animals use to construct a body.

Lacking even left-right symmetry, sea anemones are evolutionarily ancient. But during embryogenesis their larvae compensate for an uninspiring torso by sprouting tentacles from thickened epithelial buds surrounding their mouth. "Nematostella's body is basically a bag of epithelium," says Gibson.

"And that simplicity makes it a great system for determining how epithelial cells act collectively to shape an appendage. Taking advantage of this fast, easy and cheap experimental system, we can quickly answer questions that give us deep insight into a process, at both the mechanistic and evolutionary levels."

The all-Stowers study, led by first author Ashleigh Fritz, a graduate student at the University of Kansas School of Medicine working in the Gibson lab, began by imaging Nematostella larvae at the cellular level before, during, and immediately after "juvenile" tentacles sprang from their body.

Freshly hatched Nematostella larvae are under intense pressure to get their tentacles up and running, as they use them to pull food toward their mouths. The question was, what kind of cellular reshuffling drove these survival-dependent changes in morphology?

"We thought tentacle outgrowth might be driven by cell proliferation," says Fritz, noting that some of Nematostella's freshwater cousins sprout appendages by constant cell division.

"Instead, we observed that cells begin thickened and then thin out as tentacles elongate." In other words, the process was driven not by cell duplication along a "tentacle axis" but rather by stretching a stockpile of cells.

Embryologists call the embryonic thickening of epithelial cells that provides raw material for a mature structure a placode. "Placodes have appeared over and over throughout evolution," says Gibson, noting that placodes give rise to wings or eyes in flies and feathers and teeth in vertebrates.

"Discovering that placodes are also utilized in animals as seemingly primitive as Nematostella shows how fundamental this strategy is in evolution."

The group also showed that activation of a cellular receptor known as Notch was mandatory for tentacles to emerge from a placode. Newly hatched Nematostella larvae swimming in lab seawater laced with a drug that blocks Notch receptor activity failed to sprout tentacles.

The researchers also constructed microarrays from tissue isolated at early, mid, and late stages of tentacle extension, allowing global comparison of the collection of mRNAs, or the "transcriptome", at each stage. That effort, driven by Stowers Research Advisor Chris Seidel, Ph.D., and Ariel Paulson of the Stowers Computational Biology Core, is an obligatory step in pioneering any new model organism.

"Transcriptome analysis led us to identify novel tentacle markers," says Fritz, referring to molecular probes used to define a particular cell type. "Also gene expression patterns that we and others have identified allowed us to construct the first-ever molecular model of how tentacles are patterned."

In short, the study not only suggests universal principles underlying sculpting of epithelial structures from a placode, but also provides investigators with a toolkit to test whether specific genes drive the process.

An added bonus is that in 2007 a consortium of researchers sequenced the Nematostella genome and reported it to be more "human-like" in size and structure than that of Drosophila or another widely used model system, the nematode C. elegans. As a result, Gibson thinks that for many key questions, Nematostella may represent a better laboratory model than either.

"The common ancestor of sea anemones, flies, and humans likely had a surprisingly complex genome," he says, explaining that over millions of years of evolution flies and worms might have lost some genomic complexity. "As a result, these seemingly simple animals share some key genomic characteristics with humans and other vertebrates."

The Gibson laboratory continues to use both flies and sea anemones to ask how epithelial proliferation is controlled and why epithelial placode formation is so prevalent in developing embryos. Their next task is to develop molecular approaches to test how specific genes govern Nematostella embryogenesis.

"Right now we are actively working on experimental tools, including techniques to knockout, edit or overexpress genes in Nematostella," says Gibson. "This paper opens up new ground and lays foundation for a next round of more deeply mechanistic studies."

In addition to Seidel and Paulson, Gibson lab postdoctoral fellow Aissam Ikmi, Ph.D., also contributed to the study.

]]> Sat, 18 MAY 2013 00:32:39 AEST Columbia MO (SPX) May 06, 2013 - Researchers who unearthed the fossil specimen of an ape skeleton in Spain in 2002 assigned it a new genus and species, Pierolapithecus catalaunicus. They estimated that the ape lived about 11.9 million years ago, arguing that it could be the last common ancestor of modern great apes: chimpanzees, orangutans, bonobos, gorillas and humans.

Now, a University of Missouri integrative anatomy expert says the shape of the specimen's pelvis indicates that it lived near the beginning of the great ape evolution, after the lesser apes had started to develop separately but before the great ape species began to diversify.

Ashley Hammond, a Life Sciences Fellow in the MU Department of Pathology and Anatomical Sciences, is the first to examine the pelvis fragments of the early hominid.

She used a tabletop laser scanner attached to a turntable to capture detailed surface images of the fossil, which provided her with a 3-D model to compare the Pierolapithecus pelvis anatomy to living species.

Hammond says the ilium, the largest bone in the pelvis, of the Pierolapithecus catalaunicus is wider than that of Proconsul nyanzae, a more primitive ape that lived approximately 18 million years ago.

The wider pelvis may be related to the ape's greater lateral balance and stability while moving using its forelimbs. However, the fingers of the Pierolapithecus catalaunicus are unlike those of modern great apes, indicating that great apes may have evolved differently than scientists originally hypothesized.

"Pierolapithecus catalaunicus seemed to use a lot of upright behaviors such as vertical climbing, but not the fully suspensory behaviors we see in great apes alive today," Hammond said.

"Today, chimpanzees, orangutans, bonobos and gorillas use forelimb-dominated behaviors to swing below branches, but Pierolapithecus catalaunicus didn't have the long, curved finger bones needed for suspension, so those behaviors evolved more recently."

Hammond suggests researchers continue searching for fossils to further explain the evolution of the great apes in Africa.

"Contrary to popular belief, we're not looking for a missing link," Hammond said.

"We have different pieces of the evolutionary puzzle and big gaps between points in time and fossil species. We need to continue fieldwork to identify more fossils and determine how the species are related and how they lived. Ultimately, everything is connected."

The study, "Middle Miocene Pierolapithecus provides a first glimpse into early hominid pelvic morphology," will be published in an upcoming issue of the Journal of Human Evolution. The Department of Pathology and Anatomical Sciences is in the MU School of Medicine. Co-authors included David Alba from the Autonomous University of Barcelona in Spain and the University of Turin in Italy, Sergio Almecija from Stony Brook University in New York, and Salvador Moya-Sola from the Miquel Crusafont Institute of Catalan Palaeontology at Autonomous University of Barcelona.

]]> Sat, 18 MAY 2013 00:32:39 AEST Subscribe to our daily selection of space, military, environment and energy newsletters responseText http://visitor.constantcontact.com/manage/optin/ea?v=0016gbbKsaiGSpQFojVO8ZoHw%3D%3D