First Glimpse Into Birth of the Milky Way

For almost 20 years astrophysicists have been trying to recreate the formation of spiral galaxies such as our Milky Way realistically. Now astrophysicists from the University of Zurich present the world's first realistic simulation of the formation of our home galaxy together with astronomers from the University of California at Santa Cruz. The new results were partly calculated on the computer of the Swiss National Supercomputing Center (CSCS) and show, for instance, that there has to be stars on the outer edge of the Milky Way.

The aim of astrophysical simulations is to model reality in due consideration of the physical laws and processes. Astronomical sky observations and astrophysical simulations have to match up exactly. Being able to simulate a complex system like the formation of the Milky Way realistically is the ultimate proof that the underlying theories of astrophysics are correct. All previous attempts to recreate the formation of spiral galaxies like the Milky Way faltered on one of two points: Either the simulated spiral galaxies displayed too many stars at the center or the overall stellar mass was several times too big.

A research group jointly run by Lucio Mayer, an astrophysicist at the University of Zurich, and Piero Madau, an astronomer at University of California at Santa Cruz, is now publishing the first realistic simulation of the formation of the Milky Way in the Astrophysical Journal. Javiera Guedes and Simone Callegari, who are PhD students at Santa Cruz and the University of Zurich respectively, performed the simulation and analyzed the data. Guedes will be working on the formation of galaxies as a postdoc in Zurich from the fall.

Removing standard matter central to formation of spiral galaxies

For their study, the scientists developed a highly complex simulation in which a spiral galaxy similar to the Milky Way develops by itself without further intervention. Named after Eris, the Greek goddess of strife and discord, because of the decades of debate surrounding the formation of spiral galaxies, the simulation offers a glimpse in time lapse into almost the entire genesis of a spiral galaxy. Its origins date back to less than a million years after the Big Bang. "Our result shows that a realistic spiral galaxy can be formed based on the basic principles of the cold dark matter paradigm and the physical laws of gravity, fluid dynamics and radiophysics," explains Mayer.

The simulation also shows that in an entity that is supposed to develop into a spiral galaxy, the stars in the areas with giant cloud gas complexes have to form. In these cold molecular giant clouds, the gases exhibit extremely high densities. The star formation and distribution there does not occur uniformly, but rather in clumps and clusters. This in turn results in a considerably greater build-up of heat through local supernova explosions. Through this massive build-up of heat, visible standard matter is removed at high redshift. This prevents the formation of a concave disk in the center of the galaxy. The removal of baryonic matter, as the visible standard matter is also known, also reduces the overall mass of the gas present at the center. This results in the formation of the correct stellar mass, as can be observed in the Milky Way. At the end of the simulation, a thin, curved disk results that corresponds fully to the astronomical observations of the Milky Way in terms of the mass, angular momentum and rotation velocity ratios.

Read moer at Science Daily

Pioneering Ants Challenge Self-Organization Assumptions

Some worker ants are more equal than others.

As with other social insects, it was once thought that workers were essentially equivalent in ant colony hierarchies. But it appears that a few well-informed individuals shape group decisions by leading nestmates to new homes.

The findings could add a new dimension to ant-derived models of self-organization.

“Although self-organized systems appear very effective under the assumption that all individuals follow the same simple set of rules, the presence of key, well-informed individuals altering their behavior according to their prior experience might generally enhance performance even further,” wrote biologists from the University of Bristol and the University of Toulouse in an Aug. 24 Journal of Experimental Biology paper.

To study nest-hunting, Nathalie Stroeymeyt and colleagues Nigel Franks and Martin Giurfa collected “house-hunting” ants, or Temnothorax albipennis, from the southern coast of the United Kingdom. These small, light-brown ants make simple sand-enclosed nests in the cracks of rocks.

Moving the ants into the lab, Stroeymeyt gave them a well-supplied artificial nest. She then placed an identical empty nest site at the opposite end of the ants’ territory. Each ant’s back was painted with individually-identifiable colored spots. Webcams and motion-detection software allowed the researchers to keep track of the movements of specific ants.

One week later Stroeymeyt placed a second unfamiliar nest site in the territory and destroyed their original home. Though some ants began to run around randomly in all directions, a few ants who had already explored the alternate nest site headed directly to it.

Those ants then quickly returned to the destroyed nest to recruit followers. They repeated the process until enough had gathered at the new nest site to relocate the entire colony.

Most studies of how ants find new nest sites use colonies unfamiliar with a new territory, and assume that all workers follow the same rules. But that’s not realistic, and as a model for self-organization and distributed decision-making — ants have inspired various forms of traffic coordination, from cars to data — it might not be optimally efficient.

More at Wired Science

New Monkey and American Bird Species Found

This has been a great week for animal discoveries. A unique new primate was recently found in the Amazon and, for the first time in decades, the United States has a new bird species.

In both cases, the animals previously slipped under the radar of scientists, perhaps because the bird and the primate so closely resemble other documented species.

The new avian is a seabird, Bryan's Shearwater (Puffinus bryani), from the Hawaiian Islands, according to a paper in the journal The Condor. It's the first new species reported from the United States and Hawaiian Islands since the Po' ouli, another bird, was discovered in the forests of Maui in 1974.

DNA testing determined Bryan's Shearwater is a new species.

"It's very unusual to discover a new species of bird these days and especially gratifying when DNA can confirm our original hypothesis that the animal is unique. This bird is unique, both genetically and in appearance, and represents a novel, albeit very rare, species," said Rob Fleischer, head of the Smithsonian Conservation Biology Institute's Center for Conservation and Evolutionary Genetics.

The Bryan's Shearwater is the smallest known shearwater in the world. As you can see from the photo, it's black and white with a black or blue-gray bill and blue legs.

One of the birds was found by biologists in 1963 during the Pacific Ocean Biological Survey Program in 1963. Peter Pyle, an ornithologist at the Institute for Bird Populations, recently examined the specimen and found that it was too small to be a little shearwater (P. assimilis) and that it has a distinct appearance. Pyle's observation then prompted the genetic analysis.

As Fleischer said, this is a rare bird, so the race is already on now to protect it.

"If we can find where this species breeds, we may have a chance to protect it and keep it from going extinct,” said Andreanna Welch, an SCBI predoctoral fellow. "Genetic analysis allows us to investigate whether an animal represents an entirely different species, and that knowledge is important for setting conservation priorities and preventing extinction."

Planning is also underway to protect the new monkey species recently found in Mato Grosso, the Brazilian state with the highest rates of deforestation in the Amazon. Often these days, if a new species is identified, it's extremely rare and possibly on the road to extinction.

The monkey is "a variation" of the titi monkey. Both the titi monkey and this new one are small, long-tailed and covered with soft fur. But the new primate sports its own unique look.

"This primate has features on its head and tail that have never been observed before in other titi monkey species found in the same area," biologist Júlio Dalponte said in a World Wildlife Fund press release.

Read more at Discovery News

Exotic Galaxy Reveals Tantalizing Tale

A galaxy with a combination of characteristics never seen before is giving astronomers a tantalising peek at processes they believe played key roles in the growth of galaxies and clusters of galaxies early in the history of the Universe.

The galaxy, dubbed Speca by the team of researchers, is only the second spiral, as opposed to elliptical, galaxy known to produce large, powerful jets of subatomic particles moving at nearly the speed of light. It also is one of only two galaxies to show that such activity occurred in three separate episodes. The scientists publish their results in the journal Monthly Notices of the Royal Astronomical Society.

Giant jets of superfast particles are powered by supermassive black holes at the cores of galaxies. Both elliptical and spiral galaxies harbour such black holes, but only Speca and one other spiral galaxy have been seen to produce large jets. The jets pour outward from the poles of rapidly-rotating disks of material orbiting the black hole. The on-and-off jet episodes have been seen in a dozen ellipticals, but only one other elliptical shows evidence, like Speca, for three such distinct episodes.

"This is probably the most exotic galaxy with a black hole ever seen. It has the potential to teach us new lessons about how galaxies and clusters of galaxies formed and developed into what we see today," said Ananda Hota, of the Academia Sinica Institute of Astronomy and Astrophysics (ASIAA), in Taiwan.

The scientists believe that Speca, about 1.7 billion light-years from Earth, and the 60-some other galaxies in a cluster with it are providing a look at what young galaxies and clusters may have been like when the Universe was much younger. In the young Universe, galaxies in such clusters would have been gathering up additional material, colliding with each other, undergoing bursts of star formation, and interacting with primordial material falling into the cluster from outside.

"Speca is showing evidence for many of these phenomena," Ananda said, adding that "We hope to find many more galaxies like it with future observations, and to learn more about the processes and an environment that were much more common when the Universe was a fraction of its current age."

Speca (an acronym for Spiral-host Episodic radio galaxy tracing Cluster Accretion) first came to Ananda's attention in an image that combined data from the visible-light Sloan Digital Sky Survey and the FIRST survey done with the National Science Foundation's Very Large Array (VLA) radio telescope. Follow-up observations with the Lulin optical telescope in Taiwan and ultraviolet data from NASA's GALEX satellite confirmed that the giant lobes of radio emission, usually seen coming from elliptical galaxies, were coming from a spiral galaxy with ongoing star formation.

Ananda's team also examined the galaxy in images from the NRAO VLA Sky Survey (NVSS), then made new observations with the Giant Meterwave Radio Telescope (GMRT) in India, which observes at longer wavelengths than the VLA and is the premier telescope for observing at those long wavelengths.

With this impressive variety of data from across the electromagnetic spectrum, the researchers unravelled the galaxy's complex and fascinating history.

The radio images from the VLA FIRST survey had shown one pair of radio-emitting lobes. The VLA's NVSS images showed another, distinct pair of lobes farther from the galaxy. The GMRT images confirmed this second pair, but showed another, smaller pair close to the galaxy, presumably produced by the most-recently ejected jet particles.

"By using these multiple sets of data, we found clear evidence for three distinct epochs of jet activity," Ananda explained.

The biggest surprise -- the low-frequency nature of the oldest, outermost lobes -- gave a valuable clue about the galaxy's -- and the cluster's -- environment. The outermost radio-emitting lobes are old enough that their particles should have lost most of their energy and ceased to produce radio emission.

"We think these old, relic lobes have been 're-lighted' by shock waves from rapidly-moving material falling into the cluster of galaxies as the cluster continues to accrete matter," said Ananda.

"All these phenomena combined in one galaxy make Speca and its neighbours a valuable laboratory for studying how galaxies and clusters evolved billions of years ago," Ananda said.

Read more at Science Daily

Scientists Still Struggle to ID 9/11 Remains

In a laboratory in the center of Manhattan scientists continue to struggle to put names to the remains of victims from the September 11, 2001 attacks, some 40 percent of which are still unidentified.

"It's not a legal obligation because everybody has a death certificate. It's an ethical-moral decision," said Mechthild Prinz in the department of forensic biology at the city's Chief Medical Examiner office.

The names of the people who died in the explosions, fires and collapse in the Twin Towers on 9/11 are known, but the violence was so extreme that even a decade later it takes painstaking forensic work to match those identities to the human fragments found at the site.

The latest match made was just this week: Ernest James, who was 40 years old. He was the 1,629th victim identified out of 2,753 people killed at the World Trade Center, or 59 percent of the total.

Initially, traditional methods such as dental records, photographs and finger prints were used to identify the bodies and remains pulled from the rubble. But as the easier batches of remains were dealt with the gruesome task turned into something more akin to serious detective work -- and even that is not enough in many cases.

"We did collect 21,817 remains, so you can imagine obviously that a lot of people were fragmented in many different body parts. And since we haven't identified over a thousand people, some of them really disappeared," said Prinz, 53, who comes from Germany but has been working as a forensic scientist in New York since 1995.

Amid strict security and sanitation conditions, a team of five scientists continues to deal with 6,314 fragments of bones found in the World Trade Center area.

An AFP journalist was shown the work underway through a window in a door before being told to put on gloves and taken into a large room, where robots clean the remains before they are tested for DNA against a databank created by relatives of the deceased.

"I remember a case a few years ago which was a small piece of bone on the roof of the Deutsche Bank building. It was the size of a coin and we were able to identify someone who worked in the towers at that time," recalled Taylor Dickerson, a criminalist in the forensic biology department.

However in most cases the DNA found in the fragments turns out to be just another piece of a person already identified. As a result, the work is painfully slow: fewer than three dozen people have been identified since 2006.

Read more at Discovery News

Horses Domesticated 9,000 Years Ago in Saudi Arabia

Saudi Arabia has found traces of a civilization that was domesticating horses about 9,000 years ago, 4,000 years earlier than previously thought, the kingdom said.

"This discovery shows that horses were domesticated in the Arabian Peninsula for the first time more than 9,000 years ago, whereas previous studies estimated the domestication of horses in Central Asia dating back 5,000 years, Ali al-Ghabban, vice-chairman of the Department of Museums and Antiquities, said at a news conference late Wednesday.

The remains of the civilization were found close to Abha, in southwestern Asir province, an area known to antiquity as Arabia Felix.

The civilization, given the name al-Maqari, used "methods of embalming that are totally different to known processes," Ghabban said.

Among the remains found at the site are statues of animals such as goats, dogs, hawks, and a three foot-tall bust of a horse, Ghabban said.

"A statue of an animal of this dimension, dating back to that time, has never been found anywhere in the world," Ghabban said.

He added that archaeologists also found arrowheads, stone tools, weaving tools and mortars for pounding grain, reflecting the development of that civilization.

Read more at Discovery News

Black Hole Behemoth Found Guilty of Star's Murder

For the first time, astronomers have witnessed the violent death of a star as it happened. But this star didn't die from natural causes; it died as a result of straying too close to a black hole, whose immense tidal forces tore the unfortunate star to shreds before eating the remains.

The accused supermassive black hole resides in the center of a galaxy some 3.9 billion light-years away in the constellation Draco.

This violent event was noticed on March 29 after NASA's Swift space telescope detected X-rays being generated in the center of a distant galaxy, a galaxy with a supermassive black hole in its core that has, until now, remained dormant. Astronomers initially assumed that the X-ray signal was the onset of a gamma-ray burst, but they were wrong.

Something was strange about these emissions -- a source named Swift J1644+57 -- and after follow-up observations by the Japan-led Monitor of All-sky X-ray Image (MAXI) instrument aboard the International Space Station (ISS) and, in a separate study, the National Radio Astronomy Observatory's Expanded Very Large Array (EVLA) near Socorro, N.M., it quickly became apparent that the emissions were originating from the death throes of a star being eaten.

The two Swift J1644+57 studies appear in the Aug. 25 issue of the journal Nature.

"Incredibly, this source is still producing X-rays and may remain bright enough for Swift to observe into next year," said David Burrows, professor of astronomy at Penn State University and lead scientist for the mission's X-Ray Telescope instrument. "It behaves unlike anything we've seen before."

The working theory is that the star in question strayed too close to a supermassive black hole, approximately twice the mass of the four-million-solar-mass supermassive black hole residing in the center of the Milky Way.

As the tidal shear is so powerful close to the black hole's event horizon, the star's structure would have warped dramatically. Very quickly, the stellar plasma will have streamed around the spinning black hole, forming a superheated disk of plasma. The plasma closest to the black hole then got pulled into the event horizon, accelerating as it did so.

The rapid acceleration and complex magnetic fields nearest to the black hole then funneled the matter into the event horizon, but some of the matter escaped as jets, blasting into space at relativistic speeds (exceeding 90 percent the speed of light) from the black hole's spin axis.

Read more at Discovery News

Cod’s Surprising Immune System

Norwegian research has revealed that the immune system of cod is very different from other fish and from mammals -- a discovery that may shed light on the human immune system as well. The discovery was made after scientists sequenced the entire cod genome.

Lacks part of immune system

Up to now, scientists have believed that all higher animals (including fish) share the same basic type of immune system as humans, assumed to have stemmed from a single common origin. Now it appears that cod are lacking in that part of the immune system that normally combats infection from bacteria and parasites.

"This was a very surprising finding," says Professor Kjetill S. Jakobsen, who headed the cod-sequencing project. "Conventional wisdom holds that cod should be dead. Yet it is very much alive -- a very successful species, in fact, quite widespread in the northern seas."

Alternative immunity

One of the genes that cod lack, known as MHC II, is responsible for detecting hostile microorganisms and initiating the immune response to fight off bacteria and parasites. Cod, however, have developed an entirely different way of battling bacteria and other infections. To compensate for a lack of MHC II, cod have a higher number of another gene, MHC I. Other parts of the cod immune system are different as well.

"This is a milestone in Norwegian biological research that will have both a social and an economic impact," emphasises Professor Jakobsen.

The results from the project have recently been published in the journal Nature.

New light on autoimmune disorders

"The unique immune system of cod gives us a new perspective on the human immune system as well," asserts Professor Jakobsen. "This discovery could also provide new insight into how to combat autoimmune disorders such as psoriasis, asthma and allergies."

The sequencing of the cod genome was hosted and coordinated by the Centre for Ecological and Evolutionary Synthesis (CEES), based at the Department of Biology, University of Oslo. Activities were carried out in collaboration with other Norwegian universities and with international research institutes in Norway and abroad.

Important for aquaculture industry

With the entire cod genome sequenced, scientists are able to identify genetic variations among individual cod. This will enhance their understanding of not only the immune system but also traits such as growth rate, sexual maturation, tolerance for temperature fluctuations, and oxygen uptake.

This kind of information will benefit both the aquaculture and fisheries industries. Fish farmers are looking to selectively breed cod that is adapted to production conditions -- fish that are both resistant to disease and an attractive commercial product. Additionally, vaccines can now be developed specifically for cod.

"The challenge now," says Anne Kjersti Fahlvik, Executive Director of the Research Council's Division for Innovation, "is to realise the true potential of detailed knowledge about the cod genome. This should be approached as a joint effort between the aquaculture industry and the relevant research communities."

Read more at Science Daily

Clever Dolphins Use Shells to Catch Fish

Already famed as Earth’s first tool-using marine mammals, the bottlenose dolphins of Australia’s Shark Bay have proved handy yet again, by using conch shells to trap tasty fish, then shaking them into their mouths like sardines from a tin.

Unlike sponging, however, in which dolphins use sponges to find fishes hiding in mud, conching isn’t yet widespread in Shark Bay. It appears to be a relatively new innovation, pioneered by a few individuals and finally catching on.

“The extent to which the conch shell is manipulated and the rarity of the behavior suggest that ‘conching’ takes some skill and practice and might thus be another rare individual foraging tactic in Shark Bay,” wrote biologists led by the University of Zurich’s Michael Krutzen in Marine Mammal Science.

While that study came out in April, an August 24 press release from Australia’s Murdoch University, home of co-authors Simon Allen and Lars Bejder, reported that conching has been observed at least 6 times in the last four months. That’s as often as conching was seen between the first sighting in December 1996 and the afternoon of July 31, 2007, when during a survey of western Shark Bay the researchers spotted an unfamiliar dolphin.

As they lingered nearby, hoping to dart a biopsy sample from her skin, the dolphin dived and then surfaced with her beak lodged in a conch shell, which she waved back and forth above the water. She dove again. Before she surfaced, four more dolphins arrived. When she returned with the conch, they were waiting and watching. So were the researchers.

“Photographs were taken, with two of these clearly revealing the posterior portion of a fish protruding from the conch aperture and held in the dolphin’s jaws,” they wrote in Marine Mammal Science. “The dolphin lifted the conch out of the water and manipulated it in such a manner as to drain the water and the fish from the shell.” It appeared to be an emperor fish.

Until the researchers photographed CON — sort for “Concher,” as they code-named the dolphin — the purpose of conch-wielding was unknown. From their handful of fleeting glimpses over the years, the researchers thought it likely that dolphins were simply eating conch snails inside their shells, or perhaps showing off, as do stick-wielding, clay-throwing dolphins in the Amazon.

Almost two years later, in April 2009, the researchers saw another conching dolphin, this time in a shallow, seagrass-covered spot where a wildlife observer had seen dolphins digging through seabed with shells of baler, another large marine mollusc.

Exactly how the shells are used underwater isn’t yet known. Fish might swim into them while being chased, unwittingly turning themselves into packaged snacks. The dolphins could also use the shells like nets or containers, a possibility suggested by the wildlife observer’s report of seabed-digging.

Read more at Wired Science

Sex with Neanderthals Made Us Stronger

Mating with Neanderthals and another group of extinct hominids, Denisovans, strengthened the human immune system and left behind evidence in the DNA of people today, according to new research.

The findings add to the growing body of evidence that modern humans who left Africa around 65,000 years ago mated with Neanderthals and Denisovans -- two archaic species that lived in Europe and Asia.

The study, which appears in this week's Science, is among the first to show how the interbreeding shaped modern human genes and the attributes they pass to us.

Peter Parham, a professor of cell biology, microbiology and immunology at the Stanford University School of Medicine, and his team focused their analysis on "HLA" genes, which are fast-evolving vital components of the human immune system.

"The modern human populations who left Africa to colonize other continents were likely to have been small groups who started off with limited HLA diversity and suffered further reduction of HLA diversity due to disease," Parham told Discovery News. "Interbreeding with archaic humans introduced additional HLA variants into the modern human population that increased their genetic viability and capacity to resist infection."

He and his colleagues studied the genomes for Neanderthals and Denisovans, as well as the DNA of modern human populations. The organization Bone Marrow Donors Worldwide, as well as bone marrow registries from several countries, provided data on HLA genes.

The analysis shows that Neanderthal and Denisovan HLA genes now represent more than half of such immune system-related DNA in modern European and Asian populations. They also appear to have been later introduced into Africans.

The specific gene HLA-A, for example, is present in the Neanderthal and Denisovan genomes. It contributed this much to the following modern human populations: Up to 95.3 percent for Papua New Guineans, 80.7 percent for Japanese people, 72.2 percent for Chinese people, 51.7 percent for Europeans, and 6.7 percent for Africans.

Such percentages provide clues on how modern humans migrated and interbred. The scientists believe some modern humans migrated out of Africa 67,500 years ago. Interbreeding became evident 50,000 years ago.

"Because archaic humans had lived in Asia and Europe for hundreds of thousands of years before the modern humans arrived, their HLA alleles almost certainly were adapted to the local infections and in this way further invigorated the immune systems of the recent modern migrants," Parham said.

Some of the Europeans and Asians then went back to Africa around 10,000 years ago, bringing the newly acquired genes and their associated immunity boost with them.

Human history was "a lot more complex and interesting" than previously thought, Svante Paabo, director of the Department of Genetics at the Max Planck Institute for Evolutionary Anthropology, told Discovery News.

In separate research, Paabo and his team found that about 4 percent of the genomes of non-Africans are derived from Neanderthals and 4 to 6 percent of modern Melanesian genomes are derived from Denisovans.

This earlier research and the new study then suggest at least two possible scenarios: Either interbreeding was frequent and widespread, involving a lot of individuals, or the majority of native modern populations from certain regions are descended from individuals that did interbreed, even if such "seed" groups were relatively small. Parham suspects the latter is what happened.

Read more at Discovery News

This Diamond Planet Will Last Forever

Astronomers have found the remains of a once-massive star, now transformed into a solid diamond five times bigger than Earth.

The object circles a pulsing companion star about 4,000 light years from Earth in the constellation Serpens (The Snake), which lies about one-eighth of the way toward the center of the Milky Way galaxy.

Astronomers noticed that the steady pulses of energy coming from the star, known as J1719-1438, were regularly and minutely disturbed, a phenomenon caused by the gravitational tug of another, smaller circling object.

By measuring the pattern, scientists were able to figure out how far away the second object circles and its mass, leading to the realization that they had found a bizarre binary system, with one partner reduced to a diamond core.

"In this case, something with the mass of our sun has evolved to be something the mass of a planet -- quite extraordinary," astronomer Michael Keith, with the Australia Telescope National Facility, wrote in an email to Discovery News.

The companion to J1719-1438 never got big enough to produce elements much heavier than carbon, so after its lighter-weight hydrogen and helium were stripped away that would leave a solid core of carbon -- diamond.

"Due to the immense pressure, the carbon will be in a dense crystal-like structure, although much more closely packed than in a diamond on Earth," Keith said.

The system is now stable, with no evidence that it will change for billions of years.

"Of course, this also means that it could well have been around for a long time, just waiting for us to find it. Since it's likely to last for longer than the Earth or the sun, I would say that in this case, a diamond really is forever," Keith said.

The diamond planet was found as part of an ongoing search for pulsating stars, known as pulsars, which scientists like to use as probes.

Read more at Discovery News

'Jurassic Mother' Found in China

The earliest ancestor of most of today’s mammals has been discovered in northeast China, according to a paper in the latest issue of the journal Nature.

Named Juramaia sinensis, which means the “Jurassic mother from China,” the small, shrew-like animal spent some of its time in trees while dinosaurs thrived on land.

“Because it lived 160 million years ago, and nobody was there to sign the birth certificate of its descendants, Juramaia could be our great grandmother 160 million years removed or it could also be our great grand aunt that represents a relative on the side lines,” lead author Zhe-Xi Luo told Discovery News.

Luo, a Carnegie Museum of Natural History paleontologist, and his colleagues Chong-Xi Yuan, Qing-Jin Meng and Qiang Ji analyzed the well-preserved remains of the prehistoric animal, which was discovered in Liaoning Province.

The fossils include an incomplete skull, part of the skeleton, and even impressions of residual soft tissues, such as hair. Most importantly, they also include Juramaia’s complete set of teeth as well as its forepaw bones. These features led the paleontologists to conclude that the animal was closer to living placentals on the mammalian family tree than to pouched marsupials, such as kangaroos.

The placenta is a flattened circular organ in the uterus of pregnant eutherian (i.e. placental) mammals that nourishes and maintains the fetus through the umbilical cord.

“Marsupials, by contrast, make up for the short development of fetuses in the mother by having a longer pouch life before the fetuses become independent,” Luo said. “Marsupials just optioned for a different reproductive strategy.”

Before Juramaia’s discovery, the oldest known eutherian was Eomaia that lived 125 million years ago. DNA evidence has suggested the last common ancestor to eutherians and marsupials lived around 160 million years ago.

Its front limbs were adapted to grasp and scurry up trees, an ability that must have come in handy when so many large ground animals were stomping around below and looking for dinner. Juramaia weighed under a pound, according to the researchers. Its teeth were sharp and built for eating insects.

“So I imagine this animal to be a shew-sized insectivorous mammal that hunted insects and was capable of being active in the trees,” Luo said.

Robert Asher, a lecturer and curator at the University of Cambridge’s Museum of Zoology, told Discovery News that Luo and his team “have made a compelling case based on a good analysis,” but he added that “it is very difficult at this point in the mammalian tree to identify early members of what are now extremely diverse groups.”

Asher therefore said, “One possible alternative interpretation is that Juramaia represents an animal close to the common ancestor of marsupials and placentals, but one that is neither eutherian or metatherian (the stem group of marsupials). That would leave the previous eutherian record and calibration date of 125 million years ago intact.”

Gregory Wilson, an assistant professor in the University of Washington’s Department of Biology, fully supports the new paper’s conclusions.

Read more at Discovery News

8.74 Million Species on Earth

Census time again, but don't look for a form in the mailbox. This census estimated the number of species on Earth.

Eight million, seven hundred and four thousand eukaryote species share this planet, give or take 1.3 million. Eukaryotes have cells with nuclei and other membrane bound structures, which means bacteria and other simple organisms were excluded from the count.

But it looks like a lot of species neglected to fill out their census cards. Eighty-six percent of all land-dwelling species and 91 percent in the water have yet to be discovered and cataloged by science, according to an estimate published in PLoS Biology by the Census of Marine Life scientists.

To complete their count of life on Earth, the scientists didn't go from door to door, or crevice to cave as the case may be. They used a statistical technique to extrapolate from patterns in branches of the taxonomic classification system started 253 years ago by Carl Linnaeus.

There are 1.2 million species officially registered in the Catalogue of Life and the World Register of Marine Species. The researchers discovered numerical relationships between the higher levels of taxonomic division, like order and phylum, and the number of species. Using these patterns they were able to make a more realistic estimate of species numbers that previous guesses, which ranged from 3 to 100 million.

"We discovered that, using numbers from the higher taxonomic groups, we can predict the number of species,” said Sina Adl, one of the co-authors of the study. “The approach accurately predicted the number of species in several well-studied groups such as mammals, fishes and birds, providing confidence in the method."

Census Results for the Five Kingdoms of Eukaryotes (approximate)

•     ANIMALS - 7.77 million species (of which 953,434 have been described and cataloged)
•     PLANTS - 298,000 species (of which 215,644 have been described and cataloged)
•     FUNGI - 611,000 species (of which 43,271 have been described and cataloged)
•     PROTOZOA - 36,400 species (single-cell organisms with animal-like behavior, such as movement, of which 8,118 have been described and cataloged)
•     CHROMISTS - 27,500 species (including, brown algae, diatoms, water molds, of which 13,033 have been described and cataloged)

Many of the researchers involved in the census look forward to the discovery of the millions of species yet to be described, but they fear that many species may disappear before they are even discovered.

"We have only begun to uncover the tremendous variety of life around us," says co-author Alastair Simpson. "The richest environments for prospecting new species are thought to be coral reefs, seafloor mud and moist tropical soils. But smaller life forms are not well known anywhere. Some unknown species are living in our own backyards -- literally."

"The question of how many species exist has intrigued scientists for centuries and the answer, coupled with research by others into species' distribution and abundance, is particularly important now because a host of human activities and influences are accelerating the rate of extinctions,” said lead author Camilo Mora of University of Hawaii and Dalhousie University in Halifax, Canada.

“Many species may vanish before we even know of their existence, of their unique niche and function in ecosystems, and of their potential contribution to improved human well-being,” said Mora.

"Awaiting our discovery are a half million fungi and moulds whose relatives gave humanity bread and cheese," says Jesse Ausubel, Vice-President of the Alfred P. Sloan Foundation and co-founder of the Census of Marine Life.

Another author, Boris Worm, noted that the International Union for the Conservation of Nature has assessed only 59,508 species, of which 19,625 are classified as threatened. That means less than 1% of life on Earth is being watched for threats of extinction.

Read more at Discovery News

Ancient Wild Horses Help Unlock Past

An international team of researchers has used ancient DNA to produce compelling evidence that the lack of genetic diversity in modern stallions is the result of the domestication process.

The team, which was led by Professor Michi Hofreiter from the University of York, UK, has carried out the first study on Y chromosomal DNA sequences from extinct ancient wild horses and found an abundance of diversity.

The results, which are published in Nature Communications, suggest the almost complete absence of genetic diversity in modern male horses is not based on properties intrinsic to wild horses, but on the domestication process itself.

Professor Hofreiter said: "Unlike modern female domestic horses where there is plenty of diversity, genetic diversity in male horses is practically zero.

"One hypothesis to explain this suggests modern horses have little Y chromosome diversity because the wild horses from which they were domesticated were also not diverse, due in part to the harem mating system in horses, implying skewed reproductive success of males. Our results reject this hypothesis as the Y chromosome diversity in ancient wild horses is high. Instead our results suggest that the lack of genetic diversity in modern horses is a direct consequence of the domestication process itself."

The Y chromosome is a valuable tool in population genetics, providing a means of directly assessing evolutionary processes that only affect the paternal lineage. So far mitochondrial DNA studies have failed to discover the origin of domestic horses. However, these new Y chromosomal markers now open the possibility of solving this issue in detail.

As part of the study, researchers sequenced Y chromosomal DNA from eight ancient wild horses dating back from around 15,000 to more than 47,000 years and a 2,800-year-old domesticated horse. The results were compared to DNA sequences from Przewalski horses -- the only surviving wild horse population -- and 52 domestic horses, representing 15 modern breeds, which had been sequenced previously.

Domestication of horses dates back approximately 5,500 years. DNA from the skeletal remains of a 2,800-year-old domesticated stallion from Siberia showed that in contrast to modern horses, Y chromosomal diversity still existed several thousand years after the initial domestication event for horses.

Professor Hofreiter said: "This suggests some level of Y chromosomal diversity still existed in domestic horses several thousand years after domestication, although the lineage identified was closely related to the modern domestic lineage."

The study was carried out in Germany by Sebastian Lippold, from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. The results were then independently replicated at the Centre for GeoGenetics at Copenhagen University, Denmark.

Sebastian Lippold said: "Working on ancient Y chromosomal DNA was especially challenging but the only opportunity to investigate Y chromosomal diversity in wild horses. For now we have a first idea of ancestral diversity and therefore a better impression of how much diversity has been lost. Basically this was an important first step and points to the potential the Y chromosomal marker could have in order to further investigate domestication history in horses."

Beth Shapiro, an Assistant Professor in the Department of Biology at the Pennsylvania State University, USA, carried out the analysis and interpretation.

She said: "Most ancient DNA research until now has focused on a different part of the genome -- the mitochondrion -- which is much more abundant in cells and therefore much easier to work with when the DNA is degraded. This has been a serious limitation in ancient DNA research, because we generally only have a good idea what happened along the maternal line. Here, we've been able to look at what happened along the paternal lineage, and, probably unsurprisingly, we see something different going on in males than in females.

Read more at Science Daily

Ötzi the Iceman Murdered on a Full Stomach

A fresh analysis of Ötzi the Iceman’s stomach suggests a grisly new climax to the world’s most famous prehistory murder mystery: death by ambush, a surprise killing in the afterglow of a big meal.

Ötzi was found in 1991, frozen and fantastically preserved in ice high in the Italian Alps, where he’d perished 5,300 years ago. With his tattoos and cool tools and smart outfit, rendered by artists with soulful brown eyes under a weathered brow, he became a Copper Age celebrity. Public and scientific imagination seized on the circumstances of his life — and, of course, his death.

At first, Ötzi was thought to have frozen to death, trapped by snowstorm on a mountainside. Another possibility was ritual sacrifice. But in 2001, researchers discovered an arrow in his left shoulder, bruises and cuts on his hands and chest, signs of blunt force trauma to his head. Ötzi, it appeared, was the victim of foul play.

Combined with forensic examination of locale-specific pollen grains recovered from his body, a possible narrative of Ötzi’s final days emerged. He had strayed from his tribe’s territory, perhaps as part of a raiding party, then been chased into the mountains. Having killed two of his assailants, he carried a wounded comrade on his shoulder. After a days-long chase, one so frantic that Ötzi didn’t have time to eat, leaving his stomach empty, they’d caught and killed him.

But the new study, published August 17 in the Journal of Archaeological Science, shows that Ötzi’s stomach wasn’t empty. Using a CT scanner to look anew at Ötzi’s body, researchers led by Albert Zink of the Institute for Mummies and the Iceman determined that what was thought to be part of Ötzi’s colon is actually his stomach, having shrunk and shifted after his death.

In other parts of Ötzi’s colon, where food consumed days before his death remained, archaeologists had already found traces of red deer, ibex and grain. As for his stomach, Zink and colleagues are still analyzing the contents — but whatever they were, Ötzi’s last meal was a big one. That doesn’t fit with the idea of Ötzi dying on the run, killed after a skirmish.

Read more at Wired Science

Did Queen Hatshepsut Moisturize Herself to Death?

Queen Hatshepsut, Egypt's greatest female pharaoh, might have moisturized herself to death, according to controversial new research into the dried up contents of a cosmetic vial.

Researchers at the University of Bonn, Germany, found a highly carcinogenic substance in a flask of lotion housed at the University's Egyptian Museum.

The vessel, which featured an inscription saying it belonged to Hatshepsut, was long believed to have held perfume.

"After two years of research, it is now clear that the flacon was a kind of skin care lotion or even medication for a monarch suffering from eczema," the University of Bonn said in a statement.

The skin lotion's ingredients included large amounts of palm and nutmeg oil, polyunsaturated fats that can relieve certain skin diseases, and benzopyrene, an aromatic and highly carcinogenic hydrocarbon.

"Benzopyrene is one of the most dangerous substances we know," said pharmacologist Helmut Wiedenfeld.

Banned in today's cosmetics, the cancer-causing tar residue can be found in burnt substances and foods such barbecue, coffee, cigarette smoke, and coal tar.

"We have known for a long time that Hatshepsut had cancer and maybe even died from it," said Michael Höveler-Müller, the collection's curator.

"We may now know the actual cause," he said.

He added that cases of inflammatory skin diseases that tend to be genetic are known in Hatshepsut's family.

"If you imagine that the queen had a chronic skin disease and that she found short-term improvement from the salve, she may have exposed herself to a great risk over the years," said Wiedenfeld.

Undoubtedly one of the most extraordinary women in recorded history, Hatshepsut was the daughter of Pharaoh Tuthmosis I and wife of Tuthmosis II, her half-brother.

When her husband-brother died, she became regent for the boy-king Tuthmosis III, the child of Tuthmosis II and a concubine.

But hieroglyphic carvings suggest that Hatshepsut did not put up with that state of affairs for long: Wearing the royal headdress and a false beard, she proclaimed herself pharaoh.

She reigned from 1473 to 1458 B.C. as the fifth pharaoh of the 18th Dynasty, whose later members included Akhenaton and Tutankhamun.

Under her rule, Egypt enjoyed a peaceful and prosperous time. Yet after her death, the female pharaoh was scorned, her images and inscriptions mutilated and her monuments demolished by the jealous successor Tuthmosis III.

Hatshepsut's mummy was long lost, and some scholars even hypothesized that Tuthmosis III destroyed it.

But in 2007, Egyptian authorities announced they identified the female pharaoh's mummy in KV60A, a mummified female body found by Howard Carter in 1903 as he entered tomb KV60.

The mummy showed an overweight woman just over 5 feet tall, bald in front but with long hair in back, who died at about 50.

It appeared that the powerful woman who challenged ancient Egypt's tradition of male supremacy, experienced poor health, at least in the last part of her life.

Obese, plagued with decayed teeth, the mummy also suffered from cancer, as a metastatic deposit in the pelvic bone revealed.

Read more at Discovery News

Elusive Lager Yeast Found in Patagonia

Deep in the forests of South America's Patagonia region, scientists have tracked down the wild ancestor of the yeast that makes cold-brewing ale possible, according to a new study.

The finding provides the missing piece in a centuries-long tale of beer-drinking, today a $250 billion a year industry, that began with the first batches of European lager brewed in the cool, dank caves of Bavaria.

"People have been hunting for this thing for decades," said Chris Todd Hittinger, a University of Wisconsin-Madison genetics professor and a co-author of the study in the Proceedings of the National Academy of Sciences.

"And now we've found it. It is clearly the missing species. The only thing we can't say is if it also exists elsewhere (in the wild) and hasn't been found."

Researchers from Portugal, Argentina and the United States teamed up in the hunt for the yeast, now dubbed Saccharomyces eubayanus.

The origin of the the hybrid yeast used for making the popular golden brew has been a persistent mystery.

One element -- Saccharomyces cerevisiae, responsible for the warmer temperature fermentation of ale, wine and bread -- was well known.

But the other was a puzzle. Scientists at the New University of Lisbon, who pored over 1,000 species of known yeast in European collections in an attempt to find a match, but turned up nothing.

They expanded the search to international collaborators, and Diego Libkind of the Institute for Biodiversity and Environment Research (CONICET) in Bariloche, Argentina found a close match for the yeast in Patagonian beech trees.

The yeast seemed to thrive and spontaneously ferment in the sugar-rich bulbous formations called galls which arise when insects lay eggs on the tree's leaves.

Read more at Discovery News

Skeptics Issue $1 Million Psychic Challenge

A non-profit organization called The James Randi Educational Foundation (JREF) has announced that it is publicly offering $1 million to celebrity "psychic mediums" including James Van Praagh, Allison DuBois, Sylvia Browne, Carla Baron, John Edward, and others if they can prove their abilities in controlled experiments.

"James Van Praagh and Allison DuBois have turned the huckster art of 'cold reading' into a multi-million-dollar industry, preying on families' deepest fears and regrets," said James Randi, founder of the JREF and a renowned magician and skeptic.

The JREF's Million Dollar Challenge Director, a mentalist performer named Banachek, said, "We're issuing a challenge: If one of you can demonstrate your 'psychic' abilities on randomly chosen strangers -- not celebrities -- under mutually-agreed conditions, without relying on known cold-reading techniques such as fishing around with vague questions, and without just using Google -- we will donate our million dollars to you or to the charity of your choice."

The skeptics explained how psychics can give the appearance of getting accurate information about a person they've never met.

"Cold reading" is a set of techniques in which personal information is elicited from a person, often through vague or leading questions, and then repeated back to the person in order to persuade them that the performer has supernatural access to that information.

Another mentalism technique, called "hot reading," involves obtaining information on a person in advance, for example by researching the Internet (or, in some cases, even hiring an investigator).

James Randi has exposed such "psychic" techniques for years, including his 1986 investigation into TV faith healer Peter Popoff, who knew details of his audience members' lives, including their illnesses and home addresses.

Randi showed that Popoff was actually getting his apparently psychic (or God-given) information from his wife (who had researched certain people in the audience) via a short-wave radio and hidden earpiece.

Psychics have reason to be cautious about putting their abilities to the test. The track record of psychics is abysmal, for example when it comes to helping police find missing persons. Despite claims to the contrary, there is not a single documented case of a missing person being found or recovered due to psychic information.

The fact that psychics have failed to find high-profile missing persons cannot be denied, and is there for all to see: Countless missing people, including Natalee Holloway, Laci Peterson, Madeleine McCann, Chandra Levy, Sandra Cantu, Caylee Anthony, Elizabeth Smart, Jaycee Dugard, and so on, either remain missing to this day or were found accidentally by strangers or in the course of normal police searches.

In each case hundreds of psychics gave information about the person's location while they were missing -- and every single psychic turned out to be wrong.

Tennessee nursing student Holly Bobo, for example, has been missing for over four months despite information from hundreds of psychics across the country; one of them even predicted that she would be found alive within a few days of her disappearance. Sadly, the psychics were wrong again.

Earlier this year a psychic told Texas police that several children had been killed at a rural farmhouse, sending dozens of police to the scene; she, too, was wrong.

Of course, just because psychics have not been able to find missing persons doesn't mean that they might not have other psychic abilities. It's important to keep an open mind, and try to demonstrate psychic powers in an objective, scientific manner, under conditions that rule out deception.

The Million Dollar Challenge has been around for many years. Some psychics have claimed that the money does not really exist (as part of a Nightline primetime special that aired Friday, ABC News verified that the money is real and available, held in trust by a third party).

Others have suggested that psychics would not use their powers for personal gain (they should check out the ticket prices for appearances and workshops by some of these celebrity psychics), though of course the winning psychic could donate the $1 million to charity.

Read more at Discovery news

Orangutan Washes With Washcloth

(Orangutans are remarkably intelligent. This individual, from the Great Ape Trust of Iowa, spontaneously whistles. Another orangutan was recently filmed cleaning itself off with a washcloth. Credit: Smithsonian National Zoological Park)

An orangutan at Tokyo's Tama Zoo has become an Internet star thanks to a video that shows the tidy primate cleaning itself with a washcloth.

The two-minute clip, shot on an 86 degree day at the zoo, shows the orangutan dipping a washcloth in water, ringing it out and wiping its face and upper body. The primate even mops up spilt water droplets afterward.

A smaller orangutan carefully watches and wants to check out the washcloth, but is gently moved aside.

Most likely, the adult orangutan was taught this behavior -- since the washcloth was provided -- but it appears to be acting spontaneously, putting his knowledge to good use on a hot day when a cleansing cool-off was refreshing.

Since the little orangutan was watching, the behavior will most likely be passed down. Some years ago, Duke University scientists proved that orangutans have culture, permitting them to learn new things and share that knowledge with others.

Carel van Schaik of Duke and colleagues presented evidence for cultural transmission of 24 behaviors among orangutans. These include:

-- using leaves as protective gloves or napkins;
-- using sticks to poke into tree holes to obtain insects, to extract seeds from fruit or to scratch body parts;
-- using leafy branches to swat insects or gather water;
-- "snag-riding," the orangutan equivalent of a sport in which the animals ride falling dead trees, grabbing vegetation before the tree hits the ground;
-- emitting sounds such as "raspberries," or "kiss-squeaks," in which leaves or hands are used to amplify the sound;
-- building sun covers for nests or, during rain, bunk nests above the nests used for resting.

In the above cases, I believe the orangutans were just using what was available to them in the wild. If such studies include zoo chimps, which have access to human "tools" like washcloths, the list could probably go on and on.

The last common ancestor of humans and orangutans is thought to have lived about 15 million years ago, so the primate drive to learn and share knowledge (even if it's via unwanted eavesdropping) go way back. We share 96.4 percent of our DNA with orangutans.

Van Schaik said such findings "suggest that the first ancestral man-apes must have had a pretty solid evolutionary cultural foundation on which to build."

Environment helps in that process. The orangutan exhibit at the Tama Zoo opened on April 28, 2005 and took almost 2 years and around 1 billion yen to build, according to Tokyo Guidebook. The exhibit includes a tall "Sky Walk" where the orangutans can swing across towers between living areas. If orangutans poke sticks into a large ant hill-type structure, they are rewarded with a sticky paste, similar to how they'd be rewarded with ants in the wild. The orangutans even have a vending machine that they operate to get drinks for themselves.

More at Discovery News

Bulletproof Skin Made From Spider Silk

Just last week we learned about spiders coming to the aid of burn victims. Now it looks like our friendly neighborhood arachnids are being used to create the ultimate superhero power: bulletproof human skin.

Well, almost.

In her new project, 2.6g 329m/s, Dutch artist Jalila Essaidi, along with Forensic Genomics Consortium Netherlands, created a swatch of nearly bulletproof skin made from spider silk and human skin cells. The project takes its name from the maximum weight and velocity a Type 1 bulletproof vest can withstand from a .22 calibre Long Rifle bullet.

By grafting spider silk between the epidermis and dermis, the skin was able to stop a bullet that was fired at a reduced speed. However, it failed to repel a bullet that was fired at normal speed from a .22 calibre rifle.

But that's fine with Essaidi. She's more interested in the conversation that her project will generate.

"With this work I want to show that safety in its broadest sense is a relative concept, and hence the term bulletproof," Essaidi said in a press release. "The work did stop some partially slowed bullets but not the one at full speed."

"But even with the skin pierced by the bullet the experiment is still a success. It leads to the conversation about how which form of safety would benefit society."

Read more at Discovery News

Oldest Fossil on Earth Found

Microfossils found in Australia show that more than 3.4 billion years ago, bacteria thrived on an Earth that had no oxygen, a finding that boosts hopes life has existed on Mars, a study published Sunday says.

Researchers from the University of Western Australia and Oxford University say the remains of microbes, located in ancient sedimentary rocks that have triggered debate for nearly a decade, have been confirmed as the earliest fossils ever recorded.

The sample came from the remote Pilbara region of Western Australia, a site called Strelley Pool, where the microbes, after dying, had been finely preserved between quartz sand grains.

Pilbara has some of the planet's oldest rock formations, set down in the so-called Archean Eon when the infant Earth was a primeval water world, with seas that were the temperature of a hot bath.

In 2002, another team of scientists, working in the same region just 35 kilometers (20 miles) away, said they had found bacteria fossils in the same formation.

But the claim was disputed, with some experts saying that the tiny pockmarks were not the signatures of once-living organisms but the result of mineralization of the rocks.

Drawing on the latest electron microscopy and spectroscopy techniques, the authors of the new study say they have triple proof that their sample is biological in origin.

The microbes fed on sulphur compounds to survive, they believe.

The marks measure only about 10 millionths of a meter (0.0004 inches) long.

Their shape and clustering are not only consistent with bacterial cells, say the scientists.

They also have minute crystals of pyrite, an iron-and-sulphur compound also known as fool's gold, which are a clear by-product of metabolising sulphur and sulphates, according to their argument.

The team, led by David Wacey of the University of Western Australia, report the finding in the journal Nature Geoscience.

Read more at Discovery News

Scientists reveal health benefits of breeding with Neanderthals

Interbreeding between the two species between 65,000 and 90,000 years ago speeded up modern man’s rapid rise to the head of the evolutionary tree, it is claimed.

It was established last year that a small part of the human genome can be traced back to Neanderthals.

But Prof Peter Parham, an expert in immunology at Stanford medical school in California, has now proved how this instilled a “hybrid vigour” in Homo sapiens that allowed them to go on to populate the world.

According to The Sunday Times, crossbreeding provided humans with a ready-mixed cocktail of disease-resistant genes when the species first ventured out of its native Africa.

This, in effect, speeded up man’s global dominance as they did not need to wait for evolution to do the job, it was claimed.

Matt Pope, a senior research fellow in the Department for Archaeologist at University College London, said the latest study presented exciting evidence of man’s relationship with his ancestors.

Read more at The Telegraph

The Man Who Stole The Mona Lisa

August 21st 2011 marks the one hundred year anniversary of the theft of the Mona Lisa by Leondardo da Vinci from the Louvre in Paris.

The portrait was taken by Vincenzo Peruggia, an Italian man, who took the opportunity to relieve the four iron wall-pegs of their famous charge and walk out with it under his painters smock.

The theft was not noticed until the following day and it consequently remained missing for two years before it’s new owner unwittingly came forward.

The theft made international headlines at the time but has become largely forgotten in modern society, However, a new documentary feature, entitled “The Missing Piece – The Truth Behind The Man Who Stole the Mona Lisa” goes to great lengths, with the participation of Vincenzo’s now 84 year-old daughter Celestina, to uncover exactly what happened and why.


Screening of the documentary are likely to be limited so if you manage to track it down make sure to share your experience of it in the comments below.

Source: MonaLisaMissing.com