Feb 25, 2012

NASA Urges Vigilance For Weird Fireballs

A strange breed of fireball is streaking through the skies this month, and NASA is urging folks on the ground to take notice.

February's fireballs -- a term that describes meteors that appear brighter in the sky than Venus -- aren't more numerous than normal, but their appearance and trajectory are odd, experts say.

"These fireballs are particularly slow and penetrating," meteor expert Peter Brown, a physics professor at the University of Western Ontario, said in a statement. "They hit the top of the atmosphere moving slower than 15 kilometers per second (33,500 mph), decelerate rapidly and make it to within 50 kilometers (31 miles) of Earth’s surface."

Beginning February With a Bang

The month's fireball action began on Feb. 1, when a meteor lit up the skies over central Texas, putting on a dazzling show for people in the Dallas-Fort Worth area.

"It was brighter and long-lasting than anything I've seen before," said eyewitness Daryn Morran. "The fireball took about eight seconds to cross the sky. I could see the fireball start to slow down; then it exploded like a firecracker artillery shell into several pieces, flickered a few more times and then slowly burned out."

The fireball was about as bright as the full moon, and was spotted by NASA cameras in New Mexico, more than 500 miles (805 km) away. It was likely caused by an object 3 to 6 feet (1 to 2 meters) wide, NASA researchers said.

And the meteors have kept coming, well into February.

"This month, some big space rocks have been hitting Earth's atmosphere," said Bill Cooke of the Meteoroid Environment Office at NASA's Marshall Space Flight Center in Huntsville, Ala. "There have been five or six notable fireballs that might have dropped meteorites around the United States."

Oddball Fireballs

So far in February, NASA's All-Sky Fireball Network -- which currently consists of six cameras set up in Georgia, Alabama, Tennessee and New Mexico -- has photographed about half a dozen of these strange slow-moving, deep-diving fireballs. They have ranged in size from basketballs to buses.

Cooke has analyzed their orbits and determined where the strange meteors are coming from.

"They all hail from the asteroid belt, but not from a single location in the asteroid belt," he said. "There is no common source for these fireballs, which is puzzling."

The "fireballs of February" have puzzled astronomers for decades. Skywatchers first noticed an increase in the number of deep-penetrating, bright meteors during February back in the 1960s and '70s, Brown said.

Read more at Discovery News

European Neanderthals Were On the Verge of Extinction Even Before the Arrival of Modern Humans

New findings from an international team of researchers show that most Neanderthals in Europe died off around 50,000 years ago. The previously held view of a Europe populated by a stable Neanderthal population for hundreds of thousands of years up until modern humans arrived must therefore be revised.

This new perspective on the Neanderthals comes from a study of ancient DNA published February 25 in Molecular Biology and Evolution.

The results indicate that most Neanderthals in Europe died off as early as 50,000 years ago. After that, a small group of Neanderthals recolonised central and western Europe, where they survived for another 10,000 years before modern humans entered the picture.

The study is the result of an international project led by Swedish and Spanish researchers in Uppsala, Stockholm and Madrid.

“The fact that Neanderthals in Europe were nearly extinct, but then recovered, and that all this took place long before they came into contact with modern humans came as a complete surprise to us. This indicates that the Neanderthals may have been more sensitive to the dramatic climate changes that took place in the last Ice Age than was previously thought”, says Love Dalén, associate professor at the Swedish Museum of Natural History in Stockholm.

In connection with work on DNA from Neanderthal fossils in Northern Spain, the researchers noted that the genetic variation among European Neanderthals was extremely limited during the last ten thousand years before the Neanderthals disappeared.

Older European Neanderthal fossils, as well as fossils from Asia, had much greater genetic variation, on par with the amount of variation that might be expected from a species that had been abundant in an area for a long period of time. “The amount of genetic variation in geologically older Neanderthals as well as in Asian Neanderthals was just as great as in modern humans as a species, whereas the variation among later European Neanderthals was not even as high as that of modern humans in Iceland”, says Anders Götherström, associate professor at Uppsala University.

The results presented in the study are based entirely on severely degraded DNA, and the analyses have therefore required both advanced laboratory and computational methods. The research team has involved experts from a number of countries, including statisticians, experts on modern DNA sequencing and paleoanthropologists from Denmark, Spain and the US.

Read more at Science Daily

Feb 24, 2012

Large Hadron Collider at CERN: Einstein 'was right all along'

They shocked the scientific world by claiming to have disproved Albert Einstein’s theory of special relativity.

But a report in the Science Insider journal claims that “a bad connection between a GPS unit and a computer” may have affected the reading.

Einstein's theory of special relativity, proposed in 1905, states that nothing in the universe can travel faster than the speed of light in a vacuum.

But researchers at the CERN lab near Geneva claimed they had recorded neutrinos, a type of tiny particle, travelling faster than the barrier of 186,282 miles per second.

Scientists at CERN claimed that neutrinos arrived 60 nanoseconds earlier than the 2.3 milliseconds taken by light.

The report in Science Insider said the "60 nanoseconds discrepancy appears to come from a bad connection between a fiber optic cable that connects to the GPS receiver used to correct the timing of the neutrinos' flight and an electronic card in a computer. "

"After tightening the connection and then measuring the time it takes data to travel the length of the fiber, researchers found that the data arrive 60 nanoseconds earlier than assumed," it added.

"Since this time is subtracted from the overall time of flight, it appears to explain the early arrival of the neutrinos. New data, however, will be needed to confirm this hypothesis."

Read more at The Telegraph

Black Swan Shipwreck Ordeal Comes to End

A fabulous sunken treasure recovered from a Spanish wreck in the Atlantic Ocean is flying back home from the United States, ending a five-year legal battle.

The treasure was put aboard two Spanish military C-130s planes. They took off Friday from a Florida Air Force base with 595,000 silver coins and other gold aboard. They are expected to land in Madrid's Torrejon Air Base after a 24-hour flight after two stops -- New Jersey and the Azores.

"Today a journey that began 200 years ago is finally ending. We are recovering a historical legacy and a treasure. This is not money, is our history," Spain's ambassador to the United States, Jorge Dezcallar de Mazar, was reported as saying as the planes took off.

Consisting of 18t- century silver coins weighing more than 17 tons, hundreds of gold coins, worked gold and other artifacts, the treasure has been at the center of an acrimonious international legal battle ever since it was discovered in 2007 by underwater robots from Odyssey Marine Exploration, a Florida-based treasure-hunting company.

Valued at as much as $500 million -- the richest shipwreck haul in history -- the trove was handled by Odyssey and shipped straight to the United States.

The company, which, according to earnings statements, spent $2.6 million to retrieve, transport, store and conserve the precious cargo, has been unable to remove the silver and gold coins from warehouses at the Numismatic Guaranty Corporation in Sarasota, Fla.

Immediately after the treasure was recovered, Spain filed a claim arguing that the treasure originated from the Nuestra Senora de las Mercedes. This was a 36-gun Spanish frigate which sunk off the coast of Portugal in 1804 with 200 people aboard following a battle with four British Navy ships.

According to an international maritime law known as doctrine of sovereign immunity, active-duty naval vessels on a non-commercial mission remain the property of the countries that commissioned them. Spain thus claimed the exclusive property of the wreck and its cargo.

Odyssey argued there was not enough evidence to prove the wreck, which they codenamed "Black Swan," was the Mercedes and even if that were the case, the ship’s last voyage, from Montevideo to Cadiz, was commercial in nature. The majority of coins on board were owned by private merchants, not by Spain, Odyssey insisted.

After a five-year court battle, and staggering revelations from WikiLeaks documents, a U.S. federal judge established that the United States had no jurisdiction in the case and ordered the treasure returned to Spain by Friday.

For days, a team of Spanish numismatic experts examined the precious coins, overlooking their packing into the same white plastic containers in which the coins were brought to the U.S. in 2007.

The cargo planes took off with the treasure despite an emergency appeal made by Peru to the U.S. Supreme Court on Thursday.

Read more at Discovery News

Dry Spells Caused Mayan Civilization Fall

The collapse of the ancient Mayan civilization may have been linked to relatively modest dry spells, researchers now say.

The ancient Mayan empire once stretched across an area about the size of Texas, with cities and fields occupying what is now southern Mexico and northern Central America, including the countries of Guatemala, Belize, El Salvador and Honduras. The height of the Mayan empire, known as the Classic period, reached from approximately A.D. 250 to at least A.D. 900.

The ancient Maya had what was arguably the most advanced civilization in the Americas. For instance, they made dramatic breakthroughs in astronomy that helped them very accurately predict where the moon and other planets would be in the sky centuries in the future. They also left behind many books and stone inscriptions regarding the stories of their gods and the history of their divine kings and queens.

For unknown reasons, the ancient Mayan civilization then disintegrated more than a millennium ago. The number of people declined catastrophically to a fraction of the empire's former size, and the ruins of its great cities are now largely overgrown by jungle.

Scientists have long drawn connections between the slow decline of the ancient Maya, which took about two centuries, "to climate change, and especially to drought," said researcher Martín Medina-Elizalde at the Yucatan Center for Scientific Research in Mexico. "No sound estimates had been made about the severity of this drought, but some have suggested extreme scenarios."

To see how much rainfall the ancient Maya saw before the demise of their civilization, the researchers combined the four most detailed records of past climate changes known regarding the civilization's collapse — three from nearby lakes and one from a stalagmite, a mineral formation that grows upward from a cave floor. This helped develop a model of "the region's balance between evaporation and rainfall," Medina-Elizalde said.

The scientists found that rainfall in the region decreased episodically for periods as long as a decade at a time.

"Our results show rather modest rainfall reductions between times when the Classic Maya civilization flourished and its collapse between 800 to 950," said researcher Eelco Rohling, a paleoclimatologist at the University of Southampton in England. "These reductions amount to only 25 to 40 percent in annual rainfall, but they were large enough for evaporation to become dominant over rainfall, and open water availability was rapidly reduced. The data suggest that the main cause was a decrease in summer storm activity."

The timing of these dry spells might help explain why modest reductions in rainfall still may have helped cause the demise of a well-established civilization.

"Summer was the main season for cultivation and replenishment of Maya freshwater storage systems and there are no rivers in the Yucatan lowlands," Rohling said.

It appeared to Rohling that the ancient Maya had become reliant on continuous rainfall supplies, and had stretched the capacity of their farmlands to a fine limit based on normal levels of rain. "Then, even a rather subtle climatic change was enough to create serious problems," he told LiveScience. "Societal disruptions and abandonment of cities are likely consequences of critical water shortages, especially because there seems to have been a rapid repetition of multiyear droughts."

Rohling emphasized they are not saying that climate ended the ancient Mayan civilization. "We are documenting that there was a reduction in rainfall, and that reservoirs of water were evaporating," he said. This may in turn have led to societal unrest or diseases or both, "which are more likely to explain the actual collapse of society."

Read more at Discovery News

Did Life Start in a Pond, Not Oceans?

Life may have gotten its start inland, inside ponds of volcanic condensate, not in the oceans.

Modern life is more chemically compatible with conditions in venting geothermal fields, such as Yellowstone National Park, than in the ocean, even a primitive ocean, new analysis shows. The finding challenges a widely accepted theory that modern life began in a marine environment.

The study, led by biophysicist Armen Mulkidjanian with Osnabruck University in Germany, suggests life evolved inside cooled inland ponds formed from condensation from volcanic activity deep inside the Earth. Life later would have spread into the oceans.

Stoking scientists’ interest in the chemical origins of life is a long-standing puzzle about why it has such high amounts of potassium, relative to the amounts of sodium.

“The basic question is whether the observed high potassium-sodium ratio reflect the historical environment in which life originated or underwent early evolution, or instead reflects some underlying chemical necessity, such as better functioning of certain cellular components, such as RNA or protein enzymes in a high potassium environment,” Harvard Medical School biologist Jack Szostak wrote in an email to Discovery News.

The new research provides a possible explanation for the potassium-sodium mismatch. Scientists say the composition of inorganic ions in all modern cells matches the chemistry of geothermal vapor condensate -- not the ocean.

If this vapor condensed into ponds filled with carbon, nitrogen, phosphate and other building blocks for life, the environment would have been a natural starting point for cells to evolve biochemical processes, the scientists say.

In contrast, water of the early oceans should have contained 40 times more sodium than potassium, among other conditions not conducive to the origin of the first cells, Mulkidjanian wrote in an email to Discovery News.

“We have proposed that protocells evolved in habitats with a high potassium-sodium ratio and relatively high concentrations of zinc, manganese and phosphorous compounds,” he said.

o suggest otherwise, he added, means that the first cells already had sophisticated membranes as well as the enzymes to transport and/or block ions.

“We believe that it is too much of a stretch,” Mulkidjanian wrote. “The scenario that we suggest is physically and geochemically plausible.”

Read more at Discovery News

Feb 23, 2012

Chemical Clues On Formation of Planetary Systems: Earth 'Siblings' Can Be Different

An international team of researchers, with the participation of IAC astronomers, has discovered that the chemical structure of Earth-like planets can be very different from the bulk composition of Earth. This may have a dramatic effect on the existence and formation of the biospheres and life on Earth-like planets.

The study of the photospheric stellar abundances of the planet-host stars is the key to understanding how protoplanets form, as well as which protoplanetary clouds evolve planets and which do not. These studies, which have important implications for models of giant planet formation and evolution, also help us to investigate the internal and atmospheric structure and composition of extrasolar planets..

Theoretical studies suggest that C/O and Mg/Si, are the most important elemental ratios in determining the mineralogy of terrestrial planets, and they can give us information about the composition of these planets. The C/O ratio controls the distribution of Si among carbide and oxide species, while Mg/Si gives information on the silicate mineralogy. In 2010 Bond et al. (2010b) carried out the first numerical simulations of planet formation in which the chemical composition of the proto-planetary cloud was taken as an input parameter. Terrestrial planets were found to form in all the simulations with a wide variety of chemical compositions so these planets might be very different from Earth.

Delgado Mena et al. (2010) have carried out the first detailed and uniform study of C, O, Mg and Si abundances for 61 stars with detected planets and 270 stars without detected planets from the homogeneous high-quality unbiased HARPS GTO sample. They found mineralogical ratios quite different from those in the Sun, showing that there is a wide variety of planetary systems which are unlike the Solar System. Many planetary-host stars present a Mg/Si value lower than 1, so their planets will have a high Si content to form species such as MgSiO3. This type of composition can have important implications for planetary processes like plate tectonics, atmospheric composition and volcanism.

'There could be billions of Earth-like planets in the Universe but a great majority of them may have a totally different internal and atmospheric structure. Building planets in chemically non-solar environments (which are very common in the Universe) may lead to the formation of strange worlds, very different from the Earth! The amount of radioactive and some refractory elements (especially Si) may have drastic implications for planetary processes such as plate tectonics and volcanic activity,' concludes Garik Israelian.

The latest numerical simulations have shown that a wide range of extrasolar terrestrial planet bulk compositions are likely to exist. Planets simulated as forming around stars with Mg/Si ratios less than 1 are found to be Mg-depleted (compared to Earth), consisting of silicate species such as pyroxene and various types of feldspars. Planetary carbon abundances also vary in accordance with the host stars' C/O ratio. The predicted abundances are in keeping with observations of polluted white dwarfs (expected to have accreted their inner planets during their previous red giant stage).

'The observed variations in the key C/O and Mg/Si ratios for known planetary host stars implies that a wide variety of extrasolar terrestrial planet compositions are likely to exist, ranging from relatively "Earth-like" planets to those that are dominated by C, such as graphite and carbide phases (e.g. SiC, TiC),' Delgado Mena stresses.

The results of Delgado Mena et al. (2010) were used in this study as they are the first to determine the abundance of all of the required elements in a completely internally consistent manner, using high quality spectra and an identical approach for all stars and elements, for a large sample of both host and non-host stars.

Read more at Science Daily

Physicists Pinpoint W Boson, Narrow Search for Higgs

Scientists have produced the most precise measurement of a fundamental particle called the W boson. It will help them search for the elusive Higgs boson, the discovery of which would be an epoch-making event.

The W boson’s new mass is 80.387 giga electron volts, or GeV, plus or minus 0.019 GeV. (Scientists often give a particle’s mass in units of energy because, according Einstein’s famous E=MC² equation, the two are interchangeable.) The most precise previous measurement had an uncertainty of about 0.060 GeV.

At the subatomic scale, such little differences are immense.

The new result is “exquisite” and places the uncertainty “in another category with respect to the past results,” wrote physicist Tommaso Dorigo in his blog. The finding was presented Feb. 23 at the Fermi National Accelerator Laboratory in Illinois.

Researchers with the CDF collaboration at Fermilab produced the estimate using data from the now-closed Tevatron, formerly the world’s premier particle accelerator, where measurements of collisions between protons and antiprotons fired around a 4-mile-long track provide insight into the subatomic world. Though CERN’s Large Hadron Collider has eclipsed the Tevatron, the result shows that the U.S. lab still has a few tricks up its sleeve.

The W boson, along with its counterpart the Z boson, are responsible for carrying the weak force, much the same way that photons convey electromagnetic force. Together with gravity and strong nuclear force, these comprise the four fundamental forces of nature. The W boson’s discovery in 1983 was a major success for the Standard Model, developed by physicists to explain the interactions of all subatomic particles and forces, and its mass is an important input for many nuclear and astrophysical calculations.

It’s also intimately linked to two other subatomic particles: the top quark, the heaviest of the six types of quarks, and the Higgs boson. “If you know the mass of any two, you know the mass of the third,” said physicist Rob Roser, co-spokesman for the CDF collaboration.

That potential extrapolation is crucial. While the Higgs boson has been theoretically predicted to exist, and is believed integral to the very essence of mass, it hasn’t actually been spotted.

Last December, researchers at the Large Hadron Collider saw hints of what may be the Higgs boson, and pegged its mass at about 125 GeV. The extra-precise measurement of the W boson fits with this measurement of the Higgs. The result also means that physicists shouldn’t expect to find the Higgs anywhere higher than 145 GeV.

All eyes are now on this final sliver of energy where the Higgs may be hiding, said physicist Ashutosh Kotwal of Duke University in North Carolina, who presented the latest results from the CDF collaboration. If the Higgs turns up there, it will confirm scientists’ theories. If it doesn’t, they will have to start looking for new, more exotic ways to explain the universe.

“It’s basically make it or break it for the Standard Model,” said Kotwal.

Read more at Wired Science

Stone Age Pebble Holds Mysterious Meaning

A colorful pebble bearing a sequence of linear incisions may be the world's oldest engraving.

The object, which will be described in the April issue of the Journal of Archaeology, dates back approximately 100,000 years ago and could also be the world’s oldest known abstract art. It was recovered from Klasies River Cave in the Eastern Cape Province of South Africa.

“Associated human remains indicate that the engraved piece was certainly made by Homo sapiens,” co-author Riaan Rifkin of the University of Witwatersrand’s Institute for Human Evolution told Discovery News.

Rifkin and colleagues Francesco d’Errico and Renata Garcia Moreno performed extensive non-invasive analyses of the object. Methods like X-ray fluorescence and microscopic analysis enabled the researchers to examine every minute detail of the ochre pebble, which appears to have split off from a once larger piece.

The scientists conclude that humans intentionally made the sub-parallel linear incisions on the Middle Stone Age pebble.

“Upon engraving the piece with a sharp lithic implement, it is likely to have produced a markedly bright and dark red-maroon powder,” Rifkin said. “The design may therefore have been strikingly visible shortly after it was produced.”

Ochre is a mineral-rich, naturally tinted clay that primarily consists of hydrated iron oxide. Ochre was among the earliest pigments used by humans and possibly other hominids for artistic purposes. Some even refer to it as the caveman's "crayon."

The Klasies River object measures close to 3 inches in length and contains a series of seven “deep broad engraved lines and several, about 16 or so, narrower and somewhat shallower linear features,” Rifkin said. “The fragment is a remnant of a formerly semi-circular ochre pebble that likely contained a much more extensive engraved design on its surface.”

Of particular interest now is whether or not the engraver made the design with symbolic intent. Use of symbols and meaningful images is thought to have been a significant breakthrough in human development. Language, math and countless other studies are tied to this basic skill, in addition to improved communication. To this day, art permits communication of identity and other things among diverse cultures.

Both linear and crosshatch engraved patterns may have been common thousands of years ago. Similar designs appear on engraved ochres from Blombos Cave, also in South Africa, and on ostrich eggshell fragments found in the Diepkloof Rock Shelter in the Western Cape Province. Some of these, and other, similar objects may even predate the Klasies River pebble, but studies on them are ongoing.

“The employment of red ochre for symbolic purposes likely played an important role in mediating increasingly complex social relations that emerged during the Middle Stone Age,” Rifkin explained.

Christopher Henshilwood, a researcher at the University of Witwatersrand, did not work on this study, but he has examined other very early probable engravings. For example, he studied abstract markings of another piece of ochre dating to around 70,000 years ago.

In that case, the engraving consisted of a more complex geometric pattern that looks like the letter “X” repeated in a connected series.

Read more at Discovery News

'Little Horny Man:' Oldest Rock Carving of Americas

A stick figure man with a giant phallus dubbed "the little horny man" by its discoverers is the oldest rock carving found yet in the Americas, researchers say.

These findings might shed new light on when the New World was first settled, scientists added.

The time frame during which humans first reached the Americas remains hotly debated. One key to settling this controversy would involve uncovering early examples of human artifacts, such as art.

Scientists discovered one ancient sample of such art in a cave named Lapa do Santo in central-eastern Brazil. The region is home to Luzia, the oldest human skeleton found to date in South America.

Lapa do Santo is one of the largest rock shelters excavated yet in the region, a limestone cave covering an area of about 14,000 square feet (1,300 square meters). Here, researchers have found buried human remains, tools made of stone and bone, ash from hearths, and leftovers from meals of fruit and small game.

In 2009, digging about 13 feet (4 meters) below the surface, the scientists found a rock carving or petroglyph of a man packed into the side of the cave. The figure, which appears to be squatting with his arms outstretched, is about 12 inches (30 centimeters) tall from head to feet and about 8 inches (20 centimeters) wide.

"We discovered this petroglyph in the final moments of excavation at the site," said researcher Walter Alves Neves, an archaeologist and biological anthropologist at the University of São Paulo in Brazil.

The engraving is also depicted with a relatively oversized phallus about 2 inches (5 cm) long, or about as long as the man's left arm.

"We named the figure 'the little horny man,'" Neves said.

"The figure is probably linked to some kind of fertility ritual," Neves told LiveScience. "There is another site in the same region where you find paintings with men with oversized phalluses, and also pregnant women, and even a parturition (childbirth) scene."

Carbon dating and other tests of the sediment covering the petroglyph suggest the engraving dates between 9,000 and 12,000 years old. This makes it the oldest reliably dated instance of such rock art found yet in the Americas.

When this carving is compared with other examples of early rock art found in South America, it would seem that abstract forms of thinking may have been very diverse back then, which suggests that humans settled the New World relatively early, giving their art time to diversify. For instance, at one site in Argentina named Cueva de las Manos, paintings of hands predominate, while at another site there, Cueva Epullan Grande, engravings have geometric motifs.

Read more at Discovery News

Feb 22, 2012

New Bat Has Odd-Shaped Nose

A new species of bat has just been discovered in Vietnam, according to a paper published in the Journal of Mammalogy. One of the bat's most distinctive visual features is an unusual nose that somewhat resembles the head of an owl.

To see that shape in the above images, look for the bat's nostrils, which become the eyes of the "owl."

The scientific name for this newest member of the bat community is Hipposideros griffini, belonging to the family known for its distinctive noses that help bats to focus echolocation calls. The bat's pointy ears then collect the returning calls, which allow the listener to create a full and accurate mental image of its surroundings. This sophisticated system is one reason why carnivorous bats are able to hunt so well in the dark, finding tiny insects in no time at all.

The new species was discovered during a survey of bats in Vietnam over a span of three years. Eleven of 308 bats of the Hipposideros genus that were captured and handled for study displayed differing characteristics from all known taxa, so project leader Vu Dinh Thong of Hanoi's Institute of Ecology and Biological Resources and his team established the new species.

The bat's unique characteristics include a distinctive echolocation frequency, as well as size and DNA differences with other members of Hipposideros.

Thong and his team determined this after capturing the bats and measuring them for features such as forearm length, ear height, nose-leaf width, tooth row length, and body mass. Tissue samples were taken for genetic analysis. Recordings were made inside a flight tent, in front of caves, and under forest canopies, identifying calls of bats when they left their roosts and when they were foraging. The scientists used software for bat call analysis that can display color sonograms and measure frequencies.

The echolocation frequencies of the new species range from 76.6 to 79.2 kHz, which is higher than frequencies of several related bats that range from 64.7 to 71.4 kHz. Additional evidence shows that at least two of the related bat species are occupying the same geographical region, yet have retained their separate identities.

H. griffini is named after the late professor Donald Redfield Griffin of Rockefeller University in New York. Griffin was a leading world expert on bat echolocation research, which was key to identifying H. griffini as a new species. The proposed common name for this bat is “Griffin’s leaf-nosed bat.” (From the side, the nose does look more like a leaf. A flap of skin provides the shape.)

Read more at Discovery News

7 Million-Year-Old Elephant Herd Revealed in Prints

The most extensive set of fossilized mammal footprints ever found has allowed scientists to recreate how elephants lived 7 million years ago.

The footprints were discovered at a site called Mleisa 1 in the United Arab Emirates. The find was reported in a new study in the journal Royal Society Biology Letters.

Co-author Brian Kraatz told Discovery News that the trackway "shows the oldest evidence of complex social behavior within elephants."

"It's an amazing locality," added Kraatz, who is an assistant professor in the Department of Anatomy at the Western University of Health Sciences.

"Basically, this is fossilized behavior," Faysal Bibi, lead author and a researcher at the Institut International de Paléoprimatologie and the Museum für Naturkunde, was quoted as saying in a press release. "This is an absolutely unique site, a really rare opportunity in the fossil record that lets you see animal behavior in a way you couldn't otherwise do with bones or teeth."

Bibi, Kraatz and their colleagues can tell that the prehistoric elephant herd consisted of at least 13 individuals. They walked through mud and left tracks that hardened, were buried and then re-exposed by erosion. Analysis of trackway stride lengths reveals the herd contained a diversity of sizes, from adults to a young calf.

An 853-foot-long trackway of a solitary male at the same site indicates the elephants differentiated into solitary and social groups, and that these might have been sex-segregated just like in elephants today.
Among living elephants, adult females lead the herds while males disperse at sexual maturity and come back only to mate. This same type of behavior is also suggested at the Mleisa 1 site.

"The Mleisa 1 fossil trackways are the most extensive ever recorded for mammals," said William Sanders, a paleontologist at the University of Michigan who was not involved in the study. "Bibi et al.'s analysis is an exemplary and comprehensive example of what can be garnered from ancient footprints."

Read more at Discovery News

World's Deepest Land Animal Discovered

In the dark abyss of the world's deepest known cave lurks a newly found species of primitive eyeless insect, one that researchers are calling the deepest land animal ever found.

The creature, now known as Plutomurus ortobalaganensis, is one of four newly discovered species of wingless insects called springtails, which commonly live in total darkness in caves, where they feed on fungi and decomposing organic matter.

The insects were collected during the Ibero-Russian CaveX team expedition to the world's deepest known cave during the summer of 2010. The cave, Krubera-Voronja, is located in Abkhazia, a remote area near the Black Sea in the mountains of Western Caucasus, and reaches a depth of 7,188 feet (2,191 meters) below the surface.

"The CaveX team has been exploring this cave for more than 10 years, hard and dangerous work in a remote area inside the mountains," said researcher Sofia Reboleira, a cave biologist at the University of Aveiro in Portugal, adding that temperatures inside the cave range from 32.9 to 41 degrees Fahrenheit (0.5 to 5 degrees Celsius).

"Everything needs to be carried to the mountains and then through all the cave," including more than 1.24 miles (2 kilometers) of rope and 800 cave anchors, Reboleira told LiveScience. "There are no machines, only human work. At the base camp we have no freshwater, only melted snow, and the food has to be rationed to feed almost 30 persons during 30 days. Searching for cave-dwelling animals is a task that requires several hours of active search — extremely difficult in the cold conditions of the cave, because of the risk of hypothermia."

Until now, the deepest known terrestrial creatures were a scorpion and an insect known as a silverfish, found about 3,020 feet (920 meters) below Earth's surface in a cave in Mexico. P. ortobalaganensis was discovered at a depth of about 6,500 feet (1,980 m) below the surface, and trapped using cheese as a lure.

"P. ortobalaganensis has no eyes and long antennae," said researcher Enrique Baquero, a taxonomist at the University of Navarre in Spain. These features are typical of troglobionts, or cave dwellers. "Nevertheless, it has pigment, usually absent in animals that are strict troblobionts." (The creature has a grayish body covered with darker spots.)

Baquero speculated that P. ortobalaganensis only reached such low depths recently. This would explain its lack of extreme adaptations to that depth. For instance, the organism has not yet lost its pigment as many cave creatures have. Coloration helps protect against the sun, show off to mates and camouflage against predators and prey on the surface, but is pointless in lightless caves.

Read more at Discovery News

Fossilized, 'Pompeii' Forest Discovered Under Ash

About 300 million years ago, volcanic ash buried a tropical forest located in what is now Inner Mongolia, much like it did the ancient Roman city of Pompeii.

This preserved forest has given researchers the unusual opportunity to examine an ecosystem essentially frozen in place by a natural disaster, giving them a detailed look at ancient plant communities and a glimpse at the ancient climate.

This ancient, tropical forest created peat, or moist, acidic, decaying plant matter. Over geologic time, the peat deposits were subjected to high pressure and became coal, which is found in the area.

The volcano appears to have left a layer of ash that was originally 39 inches (100 centimeters) thick.

"This ash-fall buried and killed the plants, broke off twigs and leaves, toppled trees, and preserved the forest remains in place within the ash layer," the authors, led by Jun Wang of the Nanjing Institute of Geology and Palaeontology in China, wrote in an article published Monday (Feb. 20) in the journal Proceedings of the National Academy of Sciences.

The ash layer dated to about 298 million years ago, early in the Permian Period, when the supercontinent Pangea was coming together.

The researchers examined three sites with a total area of 10,764 square feet (1,000 square meters) near Wuda, China. At these sites, they counted and mapped the fossilized plants. The tallest trees that formed the upper canopy — species in the genera Sigillaria and Cordaites — grew to 82 feet (25 meters) or more. Lower down, tree ferns formed another canopy. A group of now-extinct, spore-producing trees called Noeggerathiales and palm-like cycads grew below these, they found.

Read more at Discovery News

Feb 21, 2012

Origin of Photosynthesis Revealed

Atmospheric oxygen really took off on our planet about 2.4 billion years ago during the Great Oxygenation Event. At this key juncture of our planet's evolution, species had either to learn to cope with this poison that was produced by photosynthesizing cyanobacteria or they went extinct. It now seems strange to think that the gas that sustains much of modern life had such a distasteful beginning.

So how and when did the ability to produce oxygen by harnessing sunlight enter the eukaryotic domain, that includes humans, plants, and most recognizable, multicellular life forms? One of the fundamental steps in the evolution of our planet was the development of photosynthesis in eukaryotes through the process of endosymbiosis.

This crucial step forward occurred about 1.6 billion years ago when a single-celled protist captured and retained a formerly free-living cyanobacterium. This process, termed primary endosymbiosis, gave rise to the plastid, which is the specialized compartment where photosynthesis takes place in cells. Endosymbiosis is now a well substantiated theory that explains how cells gained their great complexity and was made famous most recently by the work of the late biologist Lynn Margulis, best known for her theory on the origin of eukaryotic organelles.

In a paper "Cyanophora paradoxa genome elucidates origin of photosynthesis in algae and plants" that appeared this week in the journal Science, an international team led by evolutionary biologist and Rutgers University professor Debashish Bhattacharya has shed light on the early events leading to photosynthesis, the result of the sequencing of 70 million base pair nuclear genome of the one-celled alga Cyanophora.

In the world of plants, "Cyanophora is the equivalent to the lung fish, in that it maintains some primitive characteristics that make it an ideal candidate for genome sequencing," said Bhattacharya.

Bhattacharya and colleagues consider this study "the final piece of the puzzle to understand the origin of photosynthesis in eukaryotes." Basic understanding of much of the subsequent evolution of eukaryotes, including the rise of plants and animals, is emerging from the sequencing of the Cyanophora paradoxa genome, a function-rich species that retains much of the ancestral gene diversity shared by algae and plants.

For those unfamiliar with algae, they include the ubiquitious diatoms that are some of the most prodigious primary producers on our planet, accounting for up to 40% of the annual fixed carbon in the marine environment.

Bhattacharya leads the Rutgers Genome Cooperative that has spread the use of genome methods among university faculty. Using data generated by the Illumina Genome Analyzer IIx in his lab, Bhattacharya, his lab members Dana C. Price, Cheong Xin Chan, Jeferson Gross, Divino Rajah and collaborators from the U.S., Europe and Canada provided conclusive evidence that all plastids trace their origin to a single primary endosymbiosis.

Read more at Science Daily

Humans Are Not Naturally 'Nasty'

Biological research increasingly debunks the view of humanity as competitive, aggressive and brutish, a leading specialist in primate behavior told a major science conference Monday.

"Humans have a lot of pro-social tendencies," Frans de Waal, a biologist at Emory University in Atlanta, told the annual meeting of the American Association for the Advancement of Science.

New research on higher animals from primates and elephants to mice shows there is a biological basis for behavior such as cooperation, said de Waal, author of "The Age of Empathy: Nature's Lessons for a Kinder Society."

Until just 12 years ago, the common view among scientists was that humans were "nasty" at the core but had developed a veneer of morality -- albeit a thin one, de Waal told scientists and journalists from some 50 countries.

But human children -- and most higher animals -- are "moral" in a scientific sense, because they need to cooperate with each other to reproduce and pass on their genes, he said.

Research has disproved the view, dominant since the 19th century, typical of biologist Thomas Henry Huxley's argument that morality is absent in nature and something created by humans, said de Waal.

And common assumptions that the harsh view was promoted by Charles Darwin, the so-called father of evolution, are also wrong, he said.

"Darwin was much smarter than most of his followers," said de Waal, quoting from Darwin's "The Descent of Man" that animals that developed "well-marked social instincts would inevitably acquire a moral sense or conscience."

De Waal showed the audience videos from laboratories revealing the dramatic emotional distress of a monkey denied a treat that another monkey received; and of a rat giving up chocolate in order to help another rat escape from a trap.

Such research shows that animals naturally have pro-social tendencies for "reciprocity, fairness, empathy and consolation," said de Waal, a Dutch biologist at Emory University in Atlanta, Georgia.

"Human morality is unthinkable without empathy."

Read more at Discovery News

Hubble Reveals Weird New Exoplanet: Waterworld

Would Kevin Costner's character in the movie "Waterworld" be at home on this exoplanet?

The planet GJ 1214b was discovered in 2009 and was one of the first planets where an atmosphere was detected. In 2010, scientists were able to measure the atmosphere, finding it was likely composed mainly of water.

Now, with infrared spectra taken during transit observations by the Hubble Space Telescope, scientists say this world is even more unique, and that it represents a new class of planet: a waterworld underneath a thick, steamy atmosphere.

"GJ 1214b is like no planet we know of," said Zachary Berta of the Harvard-Smithsonian Center for Astrophysics (CfA). "A huge fraction of its mass is made up of water."

GJ 1214b is a super-Earth -- smaller than Uranus but larger than Earth -- and is about 2.7 times Earth's diameter, weighing almost seven times as much. This world is also hot: it orbits a red-dwarf star every 38 hours at a distance of 2 million kilometers, giving it an estimated temperature of 230 degrees Celsius.

Berta and a team of international astronomers used Hubble's Wide Field Camera 3 (WFC3) to study GJ 1214b when it crossed in front of its host star. During such a transit, the star's light is filtered through the planet's atmosphere, giving clues to the mix of gases.

"We're using Hubble to measure the infrared color of sunset on this world," Berta said.

Hazes are more transparent to infrared light than to visible light, so the Hubble observations help to tell the difference between a steamy and a hazy atmosphere. They found the spectrum of GJ 1214b to be featureless over a wide range of wavelengths, or colors. The atmospheric model most consistent with the Hubble data is a dense atmosphere of water vapor.

Since the planet's mass and size are known, astronomers can calculate the density, of only about 2 grams per cubic centimeter. Water has a density of 1 gram per cubic centimeter, while Earth's average density is 5.5 grams per cubic centimeter. This suggests that GJ 1214b has much more water than Earth does, and much less rock.

As a result, the internal structure of GJ 1214b would be extraordinarily different from that of our world.

"The high temperatures and high pressures would form exotic materials like 'hot ice' or 'superfluid water', substances that are completely alien to our everyday experience," Berta said.

Read more at Discovery News

It's Alive! Pleistocene Plant Blooms Again

Fruit seeds stored away by squirrels more than 30,000 years ago and found in Siberian permafrost have been regenerated into full flowering plants by scientists in Russia, a new study has revealed.

The seeds of the herbaceous Silene stenophylla are far and away the oldest plant tissue to have been brought back to life, according to lead cryologists Svetlana Yashina and David Gilichinsky of the Russian Academy of Sciences.

The latest findings could be a landmark in research of ancient biological material and the race to potentially revive other species, including some that are extinct.

And they highlight the importance of permafrost itself in the "search of an ancient genetic pool, that of preexisting life, which hypothetically has long since vanished from the earth's surface," they wrote.

The previous record for viable regeneration of ancient flora was with 2,000-year-old date palm seeds at the Masada fortress near the Dead Sea in Israel.

The latest success is older by a significant order of magnitude, with researchers saying radiocarbon dating has confirmed the tissue to be 31,800 years old, give or take 300 years.

The study, in today's issue of the Proceedings of the National Academy of Sciences, described the discovery of 70 squirrel hibernation burrows along the bank of the lower Kolyma river, in Russia's northeast Siberia, and bearing hundreds of thousands of seed samples from various plants.

"All burrows were found at depths of 20-40 meters (65 to 130 feet) from the present day surface and located in layers containing bones of large mammals such as mammoth, wooly rhinoceros, bison, horse, deer, and other representatives of fauna" from the Late Pleistocene Age.

The permafrost essentially acted as a giant freezer, and the squirreled-away seeds and fruit resided in this closed world -- undisturbed and unthawed, at an average of -7 degrees Celsius (19 Fahrenheit) -- for tens of thousands of years.

Scientists were able to grow new specimens from such old plant material in large part because the burrows were quickly covered with ice, and then remained "continuously frozen and never thawed," in effect preventing any permafrost degradation.

In their lab near Moscow, the scientists sought to grow plants from mature S. Stenophylla seeds, but when that failed, they turned to the plant's placental tissue, the fruit structure to which seeds attach, to successfully grow regenerated whole plants in pots under controlled light and temperature.

"This is an amazing breakthrough," Grant Zazula of the Yukon Paleontology Program at Whitehorse in Yukon Territory, Canada, told The New York Times.

"I have no doubt in my mind that this is a legitimate claim."

Paleaobotanists have known for years that certain plant cells can last for millennia under the right conditions.

Some earlier claims of regeneration have not held up to scientific scrutiny, but the Yashina/Gilichinsky team was careful to use radiocarbon dating to ensure that the seeds and fruit found in the permafrost were not modern contaminants from S. Stenophylla, which still grows on the Siberian tundra.

Read more at Discovery News

Feb 20, 2012

Studying the Evolution of Life's Building Blocks

Studying the origin of life at its building blocks offers a unique perspective on evolution, says a researcher at Michigan State University.

Robert Root-Bernstein, MSU physiology professor, will answer the question of why a physiologist studies the origin of life at the annual meeting of the American Association for the Advancement of Science Feb. 16-20 in Vancouver, British Columbia.

Paleontologists study ancient life and reason that each species is a modification of the previous generation. Geneticists embrace this theory and trace the lineage of genes. Root-Bernstein wondered if there could be another level of paleontology embedded in the molecules that reflect evolution from the earliest stages of life and found in prebiotic chemistry, the study of chemical reactions that may have sparked the beginnings of life.

"By studying modules built from very simple chemicals, I'm hoping that it will lead to an understanding of a molecular paleontology in modern systems," he said. "Whether it's a human or a bacterium, we're all made from the same basic modules that have more than likely been around since the beginning of time."

For example, one aspect of Root-Bernstein's research is studying the small glucose binding sequences that occur in all protein and peptides like insulin. Focusing on these basic building blocks could provide new insights into diseases such as diabetes.

Having the characteristic of taking a nontraditional view has helped further Root-Bernstein's research.

"Albert Szent-Gyorgyi, the physiologist who discovered vitamin C, once defined discovery as seeing what everyone else sees and thinking what no one else thinks," he said. "I often find that phenomena that are obvious to other people are not obvious to me."

Root-Bernstein's ability to seek the common chemical building blocks between bacteria and humans formally known as molecular complementarity, is a distinctive view. This shared set of modules could be the basis for the evolution of the chemicals systems on which life is based, he added. It could, in fact, be the essential agent controlling evolution at every level.

Read more at Science Daily

NASA Spacecraft Reveals Recent Geological Activity On the Moon

New images from NASA's Lunar Reconnaissance Orbiter (LRO) spacecraft show the moon's crust is being stretched, forming minute valleys in a few small areas on the lunar surface. Scientists propose this geologic activity occurred less than 50 million years ago, which is considered recent compared to the moon's age of more than 4.5 billion years.

A team of researchers analyzing high-resolution images obtained by the Lunar Reconnaissance Orbiter Camera (LROC) show small, narrow trenches typically much longer than they are wide. This indicates the lunar crust is being pulled apart at these locations. These linear valleys, known as graben, form when the moon's crust stretches, breaks and drops down along two bounding faults. A handful of these graben systems have been found across the lunar surface.

"We think the moon is in a general state of global contraction because of cooling of a still hot interior," said Thomas Watters of the Center for Earth and Planetary Studies at the Smithsonian's National Air and Space Museum in Washington, and lead author of a paper on this research appearing in the March issue of the journal Nature Geoscience. "The graben tell us forces acting to shrink the moon were overcome in places by forces acting to pull it apart. This means the contractional forces shrinking the moon cannot be large, or the small graben might never form."

The weak contraction suggests that the moon, unlike the terrestrial planets, did not completely melt in the very early stages of its evolution. Rather, observations support an alternative view that only the moon's exterior initially melted forming an ocean of molten rock.

In August 2010, the team used LROC images to identify physical signs of contraction on the lunar surface, in the form of lobe-shaped cliffs known as lobate scarps. The scarps are evidence the moon shrank globally in the geologically recent past and might still be shrinking today. The team saw these scarps widely distributed across the moon and concluded it was shrinking as the interior slowly cooled.

Based on the size of the scarps, it is estimated that the distance between the moon's center and its surface shank by approximately 300 feet. The graben were an unexpected discovery and the images provide contradictory evidence that the regions of the lunar crust are also being pulled apart.

"This pulling apart tells us the moon is still active," said Richard Vondrak, LRO Project Scientist at NASA's Goddard Space Flight Center in Greenbelt, Md. "LRO gives us a detailed look at that process."

As the LRO mission progresses and coverage increases, scientists will have a better picture of how common these young graben are and what other types of tectonic features are nearby. The graben systems the team finds may help scientists refine the state of stress in the lunar crust.

"It was a big surprise when I spotted graben in the far side highlands," said co-author Mark Robinson of the School of Earth and Space Exploration at Arizona State University, principal investigator of LROC. "I immediately targeted the area for high-resolution stereo images so we could create a three-dimensional view of the graben. It's exciting when you discover something totally unexpected and only about half the lunar surface has been imaged in high resolution. There is much more of the moon to be explored."

Read more at Science Daily

High Definition Polarization Vision Discovered in Cuttlefish

Cuttlefish have the most acute polarization vision yet found in any animal, researchers at the University of Bristol have discovered by showing them movies on a modified LCD computer screen to test their eyesight.

Cuttlefish and their colourblind cousins, squid and octopus, see aspects of light -- including polarized light -- that are invisible to humans, giving them a covert communication channel. The Bristol study, published today in Current Biology found that cuttlefish were much more sensitive to polarization than previously thought.

Lead researcher Dr Shelby Temple from the Ecology of Vision Laboratory at the University of Bristol said: "Just like colour and intensity, polarization is an aspect of light that can provide animals with information about the world around them. If you've ever put on a pair of polarized sunglasses glasses to cut the glare from water or the road, or gone to a recent 3D movie, then you've observed some aspects of polarized light."

With collaborators at The University of Queensland, Brisbane, Australia, the team gave cuttlefish an eye exam; but instead of measuring their acuity they measured the smallest difference in the angle of polarization the cuttlefish could detect.

Since the team could not ask the cuttlefish what they could see, they took advantage of the chameleon-like colour changes that cuttlefish use for camouflage as a way of measuring whether the animals could detect the polarized stimuli.

"We modified LCD computer monitors to show changes in polarization instead of changes in colour, and then played videos of approaching objects and watched for changes in skin colour patterns to determine if the cuttlefish could see small changes in polarization contrast," said Dr Temple. "Cuttlefish change colour all the time and respond to the slightest movement so they are an excellent model.

"Cuttlefish were much more sensitive than we expected. It was previously thought that polarization sensitivity was limited to about 10-20 degree differences, but we found that cuttlefish could respond to differences as small as one degree."

In addition to measuring the limits of polarization vision in the cuttlefish, the team also modelled how underwater scenes might look to an animal that has such high-resolution polarization vision. Using colours instead of changes in polarization angle they created images of the polarized world that humans can see and showed that there is much more information available in the polarization dimension than was previously known.

Read more at Science Daily

Even Sharks Make Friends

Sharks have a reputation for being ruthless, solitary predators, but evidence is mounting that certain species enjoy complex social lives that include longstanding relationships and teamwork.

A new study, published in the latest Animal Behaviour, documents how one population of blacktip reef sharks is actually organized into four communities and two subcommunities. The research shows for the first time that adults of a reef-associated shark species form stable, long-term social bonds.

The image contrasts with usual reports on this species, which mistakenly sinks its sharp teeth into surfers and swimmers from time to time.

Lead author Johann Mourier told Discovery News that “other species, such as grey reef sharks and scalloped hammerheads form polarized groups where individuals have a specific place, and such species may also have complex social organization.”

Mourier, a scientist at the Center for Island Research and Environmental Study (CNRS-EPHE), and colleagues Julie Vercelloni and Serge Planes conducted the study at Moorea Island in the Society archipelago, French Polynesia. A total of seven sites were surveyed on a regular basis along just over 6 miles of the north shore of Moorea. The surveys included nearly hour-long dives at a depth close to 50 feet, with the diver photographing nearby sharks.

Analysis of the gathered data determined that the sharks were not within non-random collections, but rather had organized themselves into meaningful social groups.

“The four main communities are mixed-sex communities that use a specific home range, however, within these communities individuals tend to associate more often with others of the same sex and length,” Mourier said.

In a prior study, he determined that length is proportional to a shark’s age, with male blacktip reef sharks being mature at about the age of 7 and measuring around 3.6 feet long. Females are slightly larger than males.

Mourier suspects the sharks join together in communities for protection and to avoid aggression with each other. He and his colleagues also observed a remarkable feat, “when a group of about four or five blacktip reef sharks herded a school of fishes around a coral structure.” This suggests they can cooperate with each other to hunt as a team.

Yet another perk to organizing could be that each shark becomes a comforting landmark for others in the group. As Mourier said, “Using a home range and knowing all individuals may help individuals to have a better knowledge of their environment.”

The researchers point out that sharks’ relative brain mass-body ratios have been found to be comparable to those of mammals, indicating that they are capable of complex social behaviors on par with those demonstrated in birds and mammals.

It could just be that the highly mobile nature of sharks, combined with the difficulty of following individuals in the open sea, has kept their social interactions hidden away from human eyes until recent years.

In another study, led by Demian Chapman, researchers showed that lemon sharks at the Bimini islands, Bahamas, tended to stay near their coastal birthplace for many years.

"We were very surprised to see that many lemon sharks lingered for years around the island where they were born -- often more than half of their development to adulthood,” said Chapman, a shark scientist with the Institute for Ocean Conservation Science at Stony Brook University.

Read more at Discovery News

Feb 19, 2012

X-Rays Illuminate the Interior of the Moon

Unlike Earth, our Moon has no active volcanoes, and the traces of its past volcanic activity date from billions of years ago. This is surprising because recent Moonquake data suggest that there is plenty of liquid magma deep within the Moon and part of the rocks residing there are thought to be molten. Scientists have now identified a likely reason for this peaceful surface life: the hot, molten rock in the Moon's deep interior could be so dense that it is simply too heavy to rise to the surface like a bubble in water. For their experiments, the scientists produced microscopic copies of moon rock collected by the Apollo missions and melted them at the extremely high pressures and temperatures found inside the Moon. They then measured their densities with powerful X-ray beams.

The results are published in the Journal Nature Geoscience on 19 February 2012.

The team was led by Mirjam van Kan Parker and Wim van Westrenen from VU University Amsterdam and composed of scientists from the Universities of Paris 6/CNRS, Lyon 1/CNRS, Edinburgh, and the European Synchrotron Radiation Facility (ESRF) in Grenoble.

Five decades after the Apollo missions, the formation and geological history of the Moon still hold many secrets. The astronauts not only returned 380 kg of Moon rocks to Earth but also placed many scientific instruments on the lunar surface. Last year, NASA scientists published a new model for the make-up of the interior of the Moon, using Moonquake data from these Apollo-era seismometers. Renee Weber and her colleagues claim that the deepest parts of the lunar mantle, bordering on the small metallic core, are partially molten, by up to 30 per cent. In Earth, such bodies of magma tend to move towards the surface leading to volcanic eruptions. If the deep interior of the Moon contains so much magma, why don't we see spectacular volcanic eruptions at its surface?

The driving force for vertical movement of magma is the density difference between the magma and the surrounding solid material, making the liquid magma move slowly upwards like a bubble. The lighter the liquid magma is, the more violent the upward movement will be.

To determine the density of lunar magma, Wim van Westrenen and his colleagues synthesised moon rock in their laboratory in Amsterdam, using the composition derived from Apollo samples as their "recipe." The pressures and temperatures close to the core of the Moon are more than 45,000 bar and about 1500 degrees. It is possible to generate these extreme conditions with small samples, heating them with a high electric current while squashing them in a press. By measuring the attenuation of a powerful synchrotron X-ray beam at the ESRF traversing the sample both solid and molten, the density at high pressure and high temperature could be measured. "We had to use the most brilliant X-ray beam in the world for this experiment because the magma sample is so tiny and confined in a massive, highly absorbing container. Without a bright beam of X-rays, you cannot measure these density variations," says Mohamed Mezouar from the ESRF.

The measurements at the ESRF were combined with computer simulations to calculate the magma density at any location in the Moon.

Nearly all the lunar magmas were found to be less dense than their solid surroundings, similar to the situation on Earth. There is one important exception: small droplets of titanium-rich glass first found in Apollo 14 mission samples produce liquid magma as dense as the rocks found in the deepest parts of the lunar mantle today. This magma would not move towards the surface.

Read more at Science Daily

Babies Know What's Fair

"That's not fair!" It's a common playground complaint. But how early do children acquire this sense of fairness? Before they're 2, says a new study. "We found that 19- and 21-month-old infants have a general expectation of fairness, and they can apply it appropriately to different situations," says University of Illinois psychology graduate student Stephanie Sloane, who conducted the study with UI's Renée Baillargeon and David Premack of the University of Pennsylvania.

The findings appear in Psychological Science, a journal published by the Association for Psychological Science.

In each of two experiments, babies watched live scenarios unfold. In the first, 19-month-olds saw two giraffe puppets dance around at the back of a stage. An experimenter arrived with two toys on a tray and said, "I have toys!" "Yay!" said the giraffes. Then the experimenter gave one toy to each giraffe or both to one of them. The infants were timed gazing at the scene until they lost interest. Longer looking times indicated that something was odd -- unexpected -- to the baby. In this experiment, three-quarters of the infants looked longer when one giraffe got both toys.

In the second experiment, two women faced each other with a pile of small toys between them and an empty plastic box in front of each of them. An experimenter said, "Wow! Look at all these toys. It's time to clean them up." In one scenario, one woman dutifully put the toys away, while the other kept playing -- but the experimenter gave a reward to both the worker and the slacker. In another scenario, both women put the toys away and both got a reward. The observing 21-month-old infants looked reliably longer when the worker and the slacker were rewarded equally.

"We think children are born with a skeleton of general expectations about fairness," explains Sloane, "and these principles and concepts get shaped in different ways depending on the culture and the environment they're brought up in." Some cultures value sharing more than others, but the ideas that resources should be equally distributed and rewards allocated according to effort are innate and universal.

Other survival instincts can intervene. Self-interest is one, as is loyalty to the in-group -- your family, your tribe, your team. It's much harder to abide by that abstract sense of fairness when you want all the cookies -- or your team is hungry. That's why children need reminders to share and practice in the discipline of doing the right thing in spite of their desires.

Still, says Sloane, "helping children behave more morally may not be as hard as it would be if they didn't have that skeleton of expectations."

Read more at Science Daily