Oct 18, 2014

Evidence for huge mountains that fed early life discovered

Roots of the ancient mountain range, long since eroded, were found in Northeast Brazil.
Scientists have found evidence for a huge mountain range that sustained an explosion of life on Earth 600 million years ago.

The mountain range was similar in scale to the Himalayas and spanned at least 2,500 kilometers of modern west Africa and northeast Brazil, which at that time were part of the supercontinent Gondwana.

"Just like the Himalayas, this range was eroded intensely because it was so huge. As the sediments washed into the oceans they provided the perfect nutrients for life to flourish," said Professor Daniela Rubatto of the Research School of Earth Sciences at The Australian National University (ANU).

"Scientists have speculated that such a large mountain range must have been feeding the oceans because of the way life thrived and ocean chemistry changed at this time, and finally we have found it."

The discovery is earliest evidence of Himalayan-scale mountains on Earth.

"Although the mountains have long since washed away, rocks from their roots told the story of the ancient mountain range's grandeur," said co-researcher Professor Joerg Hermann.

"The range was formed by two continents colliding. During this collision, rocks from the crust were pushed around 100 kilometers deep into the mantle, where the high temperatures and pressures formed new minerals."

As the mountains eroded, the roots came back up to the surface, to be collected in Togo, Mali and northeast Brazil, by Brazilian co-researcher Carlos Ganade de Araujo, from the University of Sao Paulo and Geological Survey of Brazil.

Dr Ganade de Araujo recognized the samples were unique and brought the rocks to ANU where, using world-leading equipment, the research team accurately identified that the rocks were of similar age, and had been formed at similar, great depths.

The research team involved specialists from a range of different areas of Earth Science sharing their knowledge, said Professor Rubatto.

From Science Daily

Best-Ever Portrait of Alexander the Great Found?

The imposing mosaic unearthed in the burial mound complex at Amphipolis in northern Greece might contain the best-ever portrait of Alexander the Great as a young man, according to a new interpretation of the stunning artwork, which depicts the abduction of Persephone.

It might also confirm previous speculation that the tomb belongs to Olympias, the mother of Alexander the Great.

The mosaic portrays the soul-escorting Hermes, Hades and Persephone. In reality, the mosaic most likely has human counterparts represented in the guise of the three mythological characters, said Andrew Chugg, author of "The Quest for the Tomb of Alexander the Great."

“I am thinking very much that Persephone should be an image of the occupant of the tomb being driven into the Underworld,” Chugg told Discovery News.

“That means an important queen of Macedon that died between 325-300 B.C. possibly at Amphipolis. So we are exactly where we always were: Olympias or Roxane,” Chugg said.

Chugg has considered Olympias (and Roxane, Alexander's Persian wife. in second place) as the person most likely buried in the magnificent tomb ever since archaeologists discovered colossal sphinxes and female statues known as Caryatids in the underground space.

According to the researcher, the female sculptures may specifically be Klodones, priestesses of Dionysus with whom Olympias consorted. The Greek historian Plutarch recorded they wore baskets on their heads filled with Olympias' pet snakes. The snakes would rear their heads out of the baskets, terrifying the male participants in Dionysiac rites and orgies.

Chugg’s speculation was indirectly confirmed by Lena Mendoni, general secretary of the Greek Ministry of Culture. In a press conference, Mendoni said that the scene in the mosaic, recounting the the abduction of Persephone, is indeed “linked with the cults of the underworld, the Orphic cult-descent into Hades and the Dionysian rites.”

“The leader of the Macedons was always the archpriest of these cults,” Mendoni said.

Family Resemblance

Chugg, who is not involved in the excavation, noted that Persephone has reddish hair in the mosaic scene.

“Roxane came from Afghanistan in central Asia. There are, and I think always were, very few redheads there. Conversely Olympias was a Molossian, where redheads were reputedly common,” Chugg said.

Therefore, Olympias remains the strongest candidate in the tomb’s occupant guessing game, Chugg said.

“We do have for sure some indications that Alexander was reddish blond, so it would be expected that one of his parents at least had similar hair,” he said.

More Connections

If Persephone should be seen as Olympias, shouldn’t Hades and Hermes have human counterparts?

Indeed, Hades looks exactly like portraits of Philip II. Crowned as a king, he averts the right side of his face: Philip’s right eye was disfigured by an arrow wound from the siege of Methone in 354 B.C., so the right side of his face could not be shown without spoiling the Hades-Philip duality.

“It is a magnificent irony to show him as carrying Olympias into the Underworld, since there were rumors she had been involved in organizing his assassination,” Chugg said.

As for Hermes, he was portrayed with particular movement, care and drama. “If he is to have a human counterpart, he should be somebody close to Olympias who preceded her into the afterlife for he precedes her into the Underworld,” Chugg said.

He noted that in the mosaic scene, Olympias may be in her thirties as a compliment to the deceased and because that matches Philip’s age at death (he was in his forties).

“Hermes looks like a young man of about 20 and there is something curiously familiar about him to me,” Chugg said.

The riddle has a simple solution, says the researcher.

“Who was 20 when Philip died and was close to Philip and Olympias? The obvious answer is that Hermes should be their only son, Alexander the Great,” Chugg said.

He noted there is a family resemblance between Hermes and Persephone. “It is not difficult to believe that they are mother and son,” Chugg said.

At the press conference, Mendoni confirmed that the scene of the abduction of Persephone strengthens the theory that the occupant of the massive tomb is a member of the Macedonian royal family.

“We have a found the scene of the abduction of Persephone in the mural of the so-called tomb of Persephone at the royal cemetery at Vergina, Greece. We have a second display of Pluto and Persephone, in a sacred marriage scene at the backrest of the marble throne found at the tomb of Eurydice, mother of Philip, in Aeges,” Mendoni said.

A recent study led by Theodore Antikas, head of the Art-Anthropological research team of the Vergina excavation, has confirmed that the so called Tomb I -- the one featuring the stunning wall painting of the Rape of Persephone -- contains he remains of at least seven individuals: an adult male, a female, a child, four babies aged 8-10 months and one fetus of 6.5 months. It was previously believed the tomb contained the remains of a male, a female and an infant.

Moreover, the same study has confirmed the so called Tomb II at Vergina most likely contains the cremated remains of Philip II, along with the bones of a woman warrior. On Philip II’s remains, Yannis Maniatis, Head of the Archaeometry Lab at the ''Demokritos'' National Scientific Research Center in Athens, found traces of a surprisingly composite multi-layered structure involving white-purple-white-beige-purple layers.

The rare white mineral huntite was the main constituent of the white layers, while the purple layers of the composite material were cloths dyed with Tyrian purple. The beige layer was a mixture of huntite, clay, beeswax and pine resin.

According to Maniatis, the whole structure resembles the cartonnage technique used in Egypt to make masks for the mummies.

“I suggest the fragments represent a mask that Philip II wore in ceremonies when he was alive. They could be religious ceremonies as he was also the highest priest. After his death and cremation they put this personal and religious item together with his golden wreath on top of his bones,” Maniatis told Discovery News.

Read more at Discovery News

Oct 17, 2014

Atomic trigger shatters mystery of how glass deforms

Throw a rock through a window made of silica glass, and the brittle, insulating oxide pane shatters. But whack a golf ball with a club made of metallic glass -- a resilient conductor that looks like metal -- and the glass not only stays intact but also may drive the ball farther than conventional clubs. In light of this contrast, the nature of glass seems anything but clear.

A new study at the Department of Energy's Oak Ridge National Laboratory, published Sept. 24 in Nature Communications, has cracked one mystery of glass to shed light on the mechanism that triggers its deformation before shattering. The study improves understanding of glassy deformation and may accelerate broader application of metallic glass, a moldable, wear-resistant, magnetically exploitable material that is thrice as strong as the mightiest steel and ten times as springy.

Whereas metals are usually crystalline, metallic glasses are amorphous in atomic structure. Amorphous metals, studied since the 1950s, have a tendency to crystallize when heated, which makes them extremely brittle. Metallic glass alloys that did not crystallize so easily were discovered at Tohoku University and Caltech in 1991 and introduced commercially in golf clubs in 2001.

Glass hangs in a metastable state in which the energy of the system is higher than the lowest-energy state the system could assume, a crystalline state. But its state is stable enough at room temperature to last a human lifetime.

"Exactly speaking, a metastable state cannot last; it evolves," said project leader Takeshi Egami, a distinguished scientist/professor at ORNL and the University of Tennessee-Knoxville who directs the Joint Institute for Neutron Sciences (JINS), a partnership of ORNL and UT. "For instance, diamond is only metastable. Graphite is a stable state. Hollywood says 'Diamonds Are Forever.' Scientifically that is completely incorrect."

Due to its relative stability, metallic glass can be melted and precision-cast into molds without going back to its most stable, crystalline state. The resulting parts do not need to be machined, which saves money. That said, metallic glass is pricey. (A club made of it can set a golfer back $800.) Regardless, it has been used in biocompatible bone implants, rust-resistant razors and scalpel blades, resilient coatings for refinery pipes, transformers with half the energy loss, Andre Agassi's tennis racquet and the scratch-resistant logo of Apple's iPhone 6.

It may gain wider application if dabbed on computer chips to reduce electromagnetic noise that produces heat. Wider deployment may drive down costs of metallic-glass watches, rings, skis and baseball bats. The material may be used in vehicle bodies and casings for smartphones and computers as well. But for metallic glass to achieve its promise, it must first overcome a long-standing problem.

"Metallic glasses are too brittle, meaning the materials easily break without significant ductile deformation," said Yue Fan, a Wigner Fellow at ORNL and the study's lead author. "It is extremely important to understand the origin of deformation in metallic glasses to engineer solutions that would increase their usefulness." Case in point: Initial prototypes shattered after as few as 40 hits. To improve ductility, which is a material's ability to be deformed without fracture, manufacturers had to resort to a composite including crystalline material. While metallic glass golf clubs remain in demand today, manufacturers stopped making them 10 years ago because they are costly.

Universal trigger Fan and Egami, with JINS postdoctoral researcher Takuya Iwashita, found through a computer simulation study that before glass shatters, one mechanism is in play during early deformation: Patches of only five or so atoms exchange atomic bonds with each other (see video). Prior to the discovery, scientists thought the number of atoms triggering deformation ranged from 20 to 600.

"This trigger was the same for stable and unstable glass," Fan said (see technical highlight). "The only difference was how triggers organized themselves. The individual triggers were identical. Until now people didn't believe a universal trigger existed and thought every case was different. But now we see some kind of universality."

The organization of universal triggers correlates with a material's ductility. This ability to deform under external stress will have to improve for metallic glasses to achieve mass-market viability.

"Our simulation study on the deformation of metallic glasses can shed light on controlling ductility," Fan said. The study compared metallic glasses that were heated to reach a liquid state at 2,000 kelvins and then cooled, either slowly or quickly, to near absolute zero kelvin, a temperature so cold that atoms barely move. In the quickly cooled glass, more of the five-atom deformation triggers, or regions of atomic bond switching, developed than in the slowly cooled glass. The greater density of triggers created more pathways by which energy could dissipate, creating a glass with greater ductility, Fan explained.

Grand challenge In crystals, atoms regularly pack into identical unit cells of well-ordered lattices. In glass, however, they sit at random distances from each other, an arrangement that infinitely increases the number of possible configurations. The same atomic chaos is true of a liquid. In fact, atomically, solid glass is a "frozen" liquid and flows, albeit over centuries.

Physics Nobel Prize winner Philip Anderson called glass "the deepest and most interesting unsolved problem in solid-state theory" due to its disordered atomic packing.

"In the 20th century we developed solid-state physics of the crystalline state," said Egami. "In crystals one unit cell is repeated many, many, many, many times, so if you understand one [cell], you understand everything. This periodicity was a major key in advancing the theory of solids. Glasses and liquids do not have this periodicity."

Atoms in the repeating cells of a crystal are like citizens under a dictatorship -- individuality is not tolerated and interactions are regimented, according to Egami. But atoms in glassy and liquid states are like democracies -- atoms and their environments are diverse. "It's the many-body problem in physics," Egami explained. "That means you can solve one or two [atomic interactions], but three already is a many-body problem that cannot be solved rigorously. It's a tremendous mathematical problem."

That makes glass a grand challenge not only in materials science but also in condensed matter physics.

"There's a huge vacuum in what we know about the science of liquid and glasses simply because it's a difficult challenge and not much has been done," Egami said. "A large portion of materials in the world are simply not understood."

Hiking the potential energy landscape

Strength varies even in materials of the same ilk. One crystalline material may be a thousand times stronger than another, whereas the strongest glass may be only three times as sturdy as the weakest. "It's surprising that strength is not that dependent on composition," Egami said.

Studying defects that weaken glass requires a different approach than investigating flaws that cripple crystal. When crystal is subjected to stress, imperfections in the lattice can dislocate rows of atoms. Glass, in contrast, does not have a lattice. It does, however, have defects -- so many that scientists cannot even define "defects" in glass. That makes the mechanism of deformation in amorphous materials like metallic glass controversial. "There are many, many ideas about how it happens, but still it is not really understood," Egami said.

The evolution of a system, such as an oxide glass or a metallic glass, is governed by its energy configuration, or underlying potential energy landscape (PEL).

Prior researchers had focused on initial and final states of systems during the deformation process. Instead, Fan, Egami and Iwashita focused on "saddle points" -- points of highest energy during an atom's movement in a system -- between neighboring minima. If minima are like valleys, saddle points are ridges that must be traversed to get to a neighboring valley. "There are many local minima on the PEL, and the system's deformation consists of the hoppings between neighboring minima," Fan said.

In glasses, the findings indicate, deformation happens when only five hikers/atoms have enough energy to climb the mountain together and cross the saddle point. Other hikers may strain themselves to do the same but lack the energy to succeed, so they return to their tents in the valley to rest.

In an unstable system, atoms can get to saddle points more easily than they can in a stable system. In a stable system, atoms have to scale taller mountains and expend more energy before they can rest in adjacent valleys.

Read more at Discovery News

How the brain leads us to believe we have sharp vision

We assume that we can see the world around us in sharp detail. In fact, our eyes can only process a fraction of our surroundings precisely. In a series of experiments, psychologists at Bielefeld University have been investigating how the brain fools us into believing that we see in sharp detail. The results have been published in the scientific magazine Journal of Experimental Psychology: General. Its central finding is that our nervous system uses past visual experiences to predict how blurred objects would look in sharp detail.

"In our study we are dealing with the question of why we believe that we see the world uniformly detailed," says Dr. Arvid Herwig from the Neuro-Cognitive Psychology research group of the Faculty of Psychology and Sports Science. The group is also affiliated to the Cluster of Excellence Cognitive Interaction Technology (CITEC) of Bielefeld University and is led by Professor Dr. Werner X. Schneider.

Only the fovea, the central area of the retina, can process objects precisely. We should therefore only be able to see a small area of our environment in sharp detail. This area is about the size of a thumb nail at the end of an outstretched arm. In contrast, all visual impressions which occur outside the fovea on the retina become progressively coarse. Nevertheless, we commonly have the impression that we see large parts of our environment in sharp detail.

Herwig and Schneider have been getting to the bottom of this phenomenon with a series of experiments. Their approach presumes that people learn through countless eye movements over a lifetime to connect the coarse impressions of objects outside the fovea to the detailed visual impressions after the eye has moved to the object of interest. For example, the coarse visual impression of a football (blurred image of a football) is connected to the detailed visual impression after the eye has moved. If a person sees a football out of the corner of her eye, her brain will compare this current blurred picture with memorised images of blurred objects. If the brain finds an image that fits, it will replace the coarse image with a precise image from memory. This blurred visual impression is replaced before the eye moves. The person thus thinks that she already sees the ball clearly, although this is not the case.

The psychologists have been using eye-tracking experiments to test their approach. Using the eye-tracking technique, eye movements are measured accurately with a specific camera which records 1000 images per second. In their experiments, the scientists have recorded fast balistic eye movements (saccades) of test persons. Though most of the participants did not realise it, certain objects were changed during eye movement. The aim was that the test persons learn new connections between visual stimuli from inside and outside the fovea, in other words from detailed and coarse impressions. Afterwards, the participants were asked to judge visual characteristics of objects outside the area of the fovea. The result showed that the connection between a coarse and detailed visual impression occurred after just a few minutes. The coarse visual impressions became similar to the newly learnt detailed visual impressions.

Read more at Science Daily

Giant Sphinx from 'Ten Commandments' Film Unearthed

Hidden for more than 90 years beneath the rolling sand dunes of Guadalupe, California, an enormous, plaster sphinx from the 1923 blockbuster movie "The Ten Commandments" has been rediscovered and is now above ground.

The public will be able to see the sphinx on display as early as next year, once it has been reconstructed — a necessity since it became weather-beaten during its stint beneath the sand, said Doug Jenzen, the executive director of the Guadalupe-Nipomo Dunes Center, who oversaw the recent excavation.

The roughly 15-foot-tall (4.6 meters) sphinx is one of 21 that lined the path to Pharaoh's City in the 1923 silent hit, directed by Cecil B. DeMille. He later remade the film, with Charlton Heston as Moses, in 1956.

"[The 1923 film] was one of the largest movie sets ever made, because they didn't have special effects," Jenzen told Live Science. "So anything that they wanted to look large, they had to build large." The facade to Pharaoh's City stood an estimated 12 stories tall and about 720 feet (219 meters) across. "It's giant," Jenzen said.

The film crew originally built the sphinxes' body parts in Los Angeles, and transported them about 165 miles (266 kilometers) to Guadalupe, where they assembled them into giant, hollow statues. The crew even built an extra sphinx so that the actors playing slaves could drag it around during filming, Jenzen said.

Legend has it that after filming ended, the movie crew dynamited the set and buried the sphinxes in a trench, but Jenzen has found little evidence of such a dramatic end. Instead, the wind, rain and sand likely collapsed and buried a large part of the set under the ever-shifting dunes. The sphinxes are in roughly the same place they were during filming, he said.

In fact, the film helped guide an excavation of the site in 2012.

"We'd work during the day, and we'd watch the movie at night to figure out what we were finding," said M. Colleen Hamilton, a historical archaeology program manager and senior historical archaeologist with Applied EarthWorks in California.

The first excavation took place in the 1990s, when the Dunes Center, then a part of the Nature Conservancy, had archaeologists comb through the abandoned movie site. They found dozens of small artifacts, including tobacco tins and cough syrup bottles — likely holding a substitute for alcohol during the Prohibition Era, which lasted from 1920 to 1933, Jenzen said.

"What objects like that tell us is that there wasn't a whole lot to do at the making of this movie," he said. "These guys had a lot of really good times before takes."

Mysterious sphinx

In 2012, the Dunes Center invited an archaeology group to survey the set again. This time, the archaeologists found the head of a sphinx about "the size of a pool table" buried in the dunes, Jenzen said.

The archaeologists excavated the fragile plaster of Paris head, now on display at the Dunes Center, but they didn't have time to exhume its body. Now, two years later, Applied EarthWorks returnedwith the goal of finishing the project.

But it wasn't to be, said Hamilton. Although the archaeologists had buried the body in sand in 2012 to protect it, the wind had uncovered the sphinx's remains, leaving a greying, crumbling mess.

"The site is basically being destroyed through erosion," Hamilton said. "It's become more critical to try to salvage some materials before they disappear."

The wind, however, helped them find the body of another sphinx. Sand had filled its hollow insides, and exposure to the moist beach air had dulled its red and ochre colors, making a careful excavation paramount.

From Oct. 6 to 14, the archaeology team, headed by Applied EarthWorks archaeologist Kholood Abdo Hintzman, slowly excavated the sphinx's body. To keep the paper-thin plaster of Paris from cracking, they wrapped it in cheesecloth soaked in a preservation chemical. Then, they carefully funneled sand out of the hollow statue, replacing the empty space with expanding insulation foam, Hamilton said.

The team could only work a few hours each day. In the morning, the thick, moist fog prevented them from doing their fragile work, and strong winds in the afternoon also stymied their progress. But, after eight days, they finally removed the body and placed it in an off-site building to dry and shrink to its normal size.

Read more at Discovery News

The Wasp That Lays Eggs Inside Caterpillars and Turns Them Into Slaves

I want you to call the last person you complained to about your “crappy” day and apologize for wasting their time. Go on. I’ll wait.
We’re all at the mercy of parasites. You, me, your dog or cat or even pet rabbit—if you’re one of those people. But rather mercifully, parasites like the tapeworms that invade our guts don’t typically kill their hosts, on account of that meaning the end of their food and shelter. One group of parasites known as parasitoids, though, shows no such mercy. They invade their hosts, use them, and unceremoniously dispatch them when they’ve had their fill.

Few parasitoids are more bizarre or disturbing than the wasps of the genus Glyptapanteles, whose females inject their eggs into living caterpillars. There, the larvae mature, feeding on the caterpillar’s fluids before gnawing through its skin en masse and emerging into the light of day. Despite the trauma, not only does the caterpillar survive—initially at least—but the larvae mind-control it, turning their host into a bodyguard that protects them as they spin their cocoons and finish maturing. The caterpillar eventually starves to death, but only after the tiny wasps emerge from their cocoons and fly away.

Because he has awesome ideas and not because he’s some kind of sadist, ecologist Arne Janssen of the University of Amsterdam brought this remarkable lifecycle into the lab a few years back to study it. What he and his colleagues confirmed for the first time is that not only do Glyptapanteles larvae actively manipulate the behavior of their hosts, but by transforming caterpillars into bodyguards, they greatly boost their chances of survival compared to their unprotected comrades.

A caterpillar stands guard over the Glyptapanteles wasps that erupted from its body. That’s a bit like you—OK there’s really nothing in the world to compare this to.
It goes a little something like this. A female Glyptapanteles wasp pounces on a caterpillar, drilling into its flesh with what is known as an ovipositor (literally, “egg placer”), and pumps up to 80 eggs into its body cavity, according to Janssen. When the eggs hatch into larvae, they begin feeding on the caterpillar’s bodily juices, taking care to avoid attacking vital organs—somewhat of a rarity for parasitoids.

“Most parasitoids eat the host completely empty,” said Janssen. “The Glyptapanteles don’t do that. We don’t know exactly why, but one of the reasons may be that if you kill the host it cannot defend you afterwards.”

Inside the caterpillar, the larvae will go through several stages, or molts, to shed their exoskeletons as they expand. During all of this, the caterpillar, which grows more and more bloated as the larvae mature, isn’t yet showing any signs of being manipulated. Incredibly, you can’t even tell it’s behaving any differently, even as it swells to the point where it looks like it’s going to burst, like a can of soda in a freezer … that’s filled with parasitic larvae instead of soda, I guess.

Inevitably, though, the larvae must make their exit. All 80 at once. Over the course of an hour. They release chemicals that paralyze the caterpillar, then each individual begins gnawing its way out. It’s a horrific happening, as you can see in the amazing National Geographic video below, yet keep in mind that the caterpillar survives this incredible trauma.

How? Well, it’s thought that the larvae time their final molt to coincide with the exit, so as they squeeze through the caterpillar’s skin, the exoskeleton they leave behind blocks the exit hole. Thus they perform their own slapdash surgery on their gravely wounded host.

If You’ll Be My Bodyguard, I Can Be Your Long-Lost Pal

As the larvae congregate in a mass and begin spinning their cocoons, the caterpillar snaps out of it and helps them, using its own silk to construct a protective covering. And you can imagine it has somewhat conflicted feelings about all of this, much like Kevin Costner’s emotional struggles in The Bodyguard.

Once everyone is done spinning, the caterpillar switches into defense mode, lashing out at not only predatory insects, but other wasps known as hyperparasitoids. The Glyptapanteles pupae (the final stage before they complete their development), you see, don’t have it so easy. In a nice little bit of poetic justice, these hyperparasitoids will inject their own eggs into Glyptapanteles.

But not if the caterpillar has anything to do with it. The bodyguard doesn’t wander, and it doesn’t eat. It dutifully stands sentry over the pupae, rearing up on its hindmost legs and violently lashing out with swift swings of its head at anything that approaches. “And we’ve also seen that occasionally they take predators into their mouthparts and just throw them away,” said Janssen. Not exactly what you’d call normal behavior for a placid vegetarian. (Though there really are some incredibly vicious carnivorous caterpillars out there.)

What Janssen found is that when he removed the caterpillar and left the pupae to fend for themselves, twice as many fell prey to either predators or hyperparasitoids. It would seem, then, that Glyptapanteles has evolved this behavior to boost its chances of survival. Interestingly, though, the caterpillar itself attracts predators that can also opportunistically attack the pupae.

“This suggests that there may also be costs involved with the behavioral changes in the caterpillar: Behavioral changes might attract some predators against which the caterpillar cannot defend the parasitoid pupae,” Janssen and his colleagues wrote in a paper. “Nevertheless, the overall effect of caterpillar presence on survival of parasitoid pupae was positive.”

But one big question remains: How on Earth are the pupae able to mind-control the caterpillar after they’ve left its body? Given the long span between the injection of the eggs and the behavioral changes, Janssen reckons it couldn’t be the initial sting. And it probably isn’t the larvae exiting the caterpillar either, because “the caterpillars do not respond strongly to disturbance during egression, but only one to two hours after the event,” he wrote.

Janssen and his colleagues may have found their answer when they dissected caterpillars that had given painful birth to larvae three to four days before. Remarkably, they found one or two larvae still hanging out inside. It could well be that they were staying behind to mind-control the host with some kind of cocktail of chemicals in order to protect their siblings, which “would represent a cost of host manipulation: some offspring are sacrificed for higher survival of their kin,” Janssen wrote.

Read more at Wired Science

Oct 16, 2014

Elephants Can Detect Rain 150 Miles Away

If you want to know when it's going to rain, ask an elephant. Apparently, they just know. That's according to new research suggesting the lumbering giants can sense when a storm is coming, even if the ominous clouds are gathering a long way off.

A team from Texas A&M, the University of Virginia, the University of New South Wales, and the University of Utah wanted to learn more about the sudden movements of elephant herds during seasonal shifts, suspecting that migrations near the end of dry seasons were somehow related to faraway thunderstorms the creatures could perhaps detect.

Using GPS trackers, the researchers analyzed the movements of 14 elephants in Africa's Namibia region over 7 years, matching weather data with herd movements. When all of the data was crunched, they found something striking: The elephants seemed to be able to "sense" storms happening up to 150 miles away, and that was the direction in which they pointed their trunks for migration.

"We don’t know if they can actually hear the thunder or if they are detecting other low-frequency sounds generated by the storms that humans can’t hear. But there is no doubt they know what direction the rain is," said Oliver Frauenfeld, assistant professor in the geography department at Texas A&M, in a statement.

The Namibia region has a short, distinct rainy season, lasting only a few weeks. Luckily, it seems, for the elephants, they are able to get some inside information on where all of that cool, life-sustaining water will be.

While the researchers aren't yet certain what specifically sets off the elephants' keen weather-sense, one side benefit is clear: If wildlife officials tasked with protecting elephants from poachers can use weather data to make predictions about where elephants will go, they have a better chance of protecting the herds.

From Discovery News

Mysterious Slab in Russia May Be a Sundial

A strange slab of rock discovered in Russia more than 20 years ago appears to be a combination sundial and moondial from the Bronze Age, a new study finds.

The slab is marked with round divots arranged in a circle, and an astronomical analysis suggests that these markings coincide with heavenly events, including sunrises and moonrises.

The sundial might be "evidence of attempts of ancient researchers to understand patterns of apparent motion of luminaries and the nature of time," study researcher Larisa Vodolazhskaya of the Archaeoastronomical Research Center at Southern Federal University in Russia told Live Science in an email.

Last year, Vodolazhskaya and her colleagues analyzed a different Bronze Age sundial, this one found in Ukraine, and discovered it to be a sophisticated instrument for measuring the hours. The work caught the eye of archaeologists in Rostov, Russia, who knew of a similar-looking artifact found in that area in 1991. That slab had been sitting in a museum in Rostov ever since its discovery, and had never been thoroughly studied.

The Rostov slab was found over the grave of a man of about 50, and dates back to the 12th century B.C., similar in age to the one found in Ukraine. Sundials from this era have also been discovered in ancient Egypt, including in the tomb of the pharaoh Seti I.

By studying the geometry of the Rostov slab, Vodolazhskaya and her colleagues discovered that the carved circles, which are arranged in a pattern spanning about 0.9 feet (0.3 meters) in diameter, correspond with the sunrises at equinoxes (days of the year when night and day are equal in length) and solstices (days of the year when day or night are at their longest).

And the Bronze Age people who created the sundial weren't only interested in the sun. The circles that didn't correspond to solar movements were linked to lunar wanderings. Because of the angle of the moon's orbit, our lone satellite goes through an 18.6-year cycle. During this cycle, when it rises, its position shifts from southerly to northerly, and its movements across the sky are relatively high and low. The Rostov slab tracks these movements with circular carvings indicating the southernmost and northernmost moonrises of these "low" and "high" moons.

The slab was found at a Bronze Age Srubna or Srubnaya site, a culture which flourished on the steppes between the Ural Mountains and Ukraine's Dneiper River. The Srubna people may have used the sun/moondial to time their annual rituals or to organize their work lives. Or, Vodolazhskaya said, the artifact may be the work of Bronze Age scientists.

Read more at Discovery News

To Nearby Dwarf Galaxies, the Milky Way is a Big Bully

Like a bully running around the playground stealing smaller kids’ lunch money, our Milky Way galaxy has been ransacking nearby dwarf galaxies, stealing their precious star-forming gases.

In a new study carried out by astronomers using NSF’s Green Bank Telescope (GBT), W.Va., and data from other ground-based radio telescopes, the dwarf galaxies that orbit closest to the Milky Way’s gravitational sphere of influence appear to be devoid of star-forming hydrogen gas, which has, in turn, stunted their growth.

“After billions of years of interaction, astronomers wondered if the nearby dwarf spheroidal galaxies have all the same star-forming ‘stuff’ that we find in more distant dwarf galaxies,” said astronomer and lead researcher Kristine Spekkens, of the Royal Military College of Canada.

Our galaxy is the largest member of a compact group of galaxies — the Milky Way has a swarm of smaller dwarf galaxies surrounding it. Very close to the Milky Way is a collection of dwarf ‘spheroidals’ that are believed to be the left-over ancient ‘crumbs’ from our galaxy’s early evolution. Further away, irregularly-shaped dwarf galaxies, which are not gravitationally bound to the Milky Way, gather and are thought to be newcomers to the galactic neighborhood.

As discussed in a paper published in the current edition of The Astrophysical Journal Letters, Spekkens’ team spotted a very definite boundary in the star-forming neutral hydrogen gas that should be contained within the surrounding dwarf galaxies. This is the most detailed survey of neutral hydrogen in nearby dwarf galaxies ever carried out.

“What we found is that there is a clear break, a point near our home Galaxy where dwarf galaxies are completely devoid of any traces of neutral atomic hydrogen,” Spekkens said in a National Radio Astronomy Observatory (NRAO) news release.

It appears that, within a distance of 1,000 light-years from the outer edge of our galaxy, the dwarf spheroidal galaxies are rare, but beyond 1,000 light-years, the dwarf irregular galaxies “flourish.”

Read more at Discovery News

Fantastically Wrong: The Murderous, Sometimes Sexy History of the Mermaid

Painter Elisabeth Jerichau-Baumann’s depiction of a mermaid with the fall’s latest fashion accessory: seaweed in place of clothing.
Hans Christian Andersen’s The Little Mermaid is a heartwarming tale of a mermaid falling in love, battling evil to be with her love, and living happily ever after as a human. Just kidding. That’s the Disney version. In Andersen’s, the young mermaid has her tongue cut out, gets burned hard by the prince when he chooses another woman, and eventually dissolves into sea foam instead of saving her own life by ritualistically stabbing said prince through the heart and bathing in his blood. Seriously.

It was for this reason that Starbucks adopted the mermaid as its logo. (No it isn’t, that’s libel. Is it still libel if I admit it’s libelous? I guess we’ll find out.) Regardless, it took mermaids millennia of mythology to land on those coffee cups. But relations weren’t always so good between our two species—mermaids have largely been thought of as hell-bent on seducing sailors into the depths, or just smashing boats with storms if they’re not really feeling like putting the effort into being charming.

Ilya Repin’s Sadko in the Underwater Kingdom, a depiction of the Russian medieval epic poem Byliny.
So why the mixed reviews? Where did the legend of the mermaid come from in the first place? From ancient deities to corporate lackeys, the history of our aquatic cousins is certainly a strange one.

According to Terry Breverton in his book Phantasmagoria: A Compendium of Monsters, Myths, and Legends, before there were mermaids, some 4,000 years ago there was a merman: Ea, the Babylonian god of the sea. He had the lower body of a fish and upper body of a human, and was one of those handy all-purpose deities, bringing humankind the arts and sciences while also finding the time to battle evil. And because he was associated with water, he was the patron god of—no joke—cleaners because, well, someone needed to be. Ea would later be co-opted by the Greeks as Poseidon and the Romans as Neptune.

The earliest mermaid-like figure was likely the ancient Syrian goddess Atargatis, who watched over the fertility of her people, as well as their general well-being. She, too, was human above the waist and fish below it, and was accordingly associated with water. The Syrians bestowed Atargatis with the biggest, most resplendent temple they could muster, which came complete with a pond of sacred fish that you probably weren’t allowed to throw coins into for a good luck.

The mermaid-esque goddess Atargatis on a Syrian coin. She holds an egg to symbolize that she protects life, and perhaps that she’s kinda hungry.
Never one to be left out of disseminating misinformation, the great Roman naturalist Pliny the Elder, whose Natural History would serve as scientific gospel for centuries to follow, wrote of the nereids. These were nymphs we’d recognize as half-human half-fish mermaids, though “the portion of the body that resembles the human figure is still rough all over with scales.” He notes that Legatus of Gaul once wrote to Emperor Augustus claiming he found a “considerable number” of them “dead upon the sea-shore.” Pliny also mentions “sea-men,” who when night falls “climb up into ships; upon which the side of the vessel where he seated himself would instantly sink downward, and if he remained there any considerable time, even go under water.”

Such maliciousness is echoed in the sirens of Greek mythology, which variously were presented as beautiful women, half-bird half-women, and as mermaids. These fiends would lure men to their deaths with some sexy singing, as Odysseus well knew. He had his men strap him to the ship’s mast to avoid falling victim as they passed the island of the sirens, while his men plugged their ears with wax.

A mermaid-merman pair from 16th-century Italian naturalist Ulisse Aldrovandi’s epic tome Monstrorum Historia, which translates as Let’s Drop Some Acid and Go Down to the River and Just Draw Things We See, Man.
And so mermaids entered European mythology with conflicting personalities: Sometimes they were portrayed as beautiful, seductive maidens—almost goddesses like Atargatis—greatly desired by lonely sailors, while also being cast as siren-esque beasts that dragged men into the inky-black depths. But whatever the portrayal, mermaids wound their way deep into the nautical lore of the Middle Ages onward.

Really, it was best to avoid mermaids and mermen, just to be sure. Olaus Magnus, the 16th century writer and cartographer whose seminal map Carta Marina obsessively cataloged the many monsters of the seas around Scandinavia, noted that fishermen maintain that if you reel in a mermaid or merman, “and do not presently let them go, such a cruel tempest will arise, and such a horrid lamentation of that sort of men comes with it, and of some other monsters joining with them, that you would think the sky should fall.” Sea-people, it was widely held, were terribly bad luck to see or snag.

John William Waterhouse’s depiction of a mermaid from 1901.
Other encounters were more harmless. In 1430 in the Netherlands, it was said that after the dikes near the town of Edam gave way during a storm, some girls rowing around in a boat found a mermaid “floundering in shallow, muddy waters,” according to the Standard Dictionary of Folklore, Mythology, and Legend. “They got her into the bat, took her home, [and] dressed her in women’s cloths,” which was a solid choice on account of her being a woman. She couldn’t be taught to speak, however, and remained totally mute.

Now, it was a pervasive ancient belief that every land animal must have a counterpart in the sea, and humans were no exception. Clearly, there must be sea cows and sea horses and sea swine out there. So while we had the mermaid representing us in sea, some claimed that things got even more specific, and that the clergy had their own aquatic representatives.

In the mid-16th century the French naturalist Guillaume Rondelet supposedly got his hands on two specimens bearing a striking resemblance to a pair of religious types: monks and bishops. The Encyclopaedia Metropolitana of 1817 describes the supposed “sea monk” accordingly: “The face was human, but coarse and clownish, the head smooth and without hair, a sort of hood resembling that of a monk covered the shoulders,” while its “lower parts ended in a spreading tail.” The “bishop fish” was “yet more wonderful, being clad by nature in the garb of a bishop.” It was taken to the king of Poland, who in his benevolence decreed it be carried back to the ocean and set free.

A bishop fish, left, and monk fish, also from Aldrovandi’s Monstrorum Historia. It’s fairly safe to assume that what observers had seen were not fish that had gone to a seminary and taken a vow of celibacy and slapped on fancy clothes, but were instead just squid.
But out at sea, the number of mermaid sightings exploded as the Age of Discovery kicked off, as men in big, expensive boats made their way around the world. John Smith, of Pocahontas fame, caught sight of one off of Newfoundland in 1614, noting that “her long green hair imparted to her an original character that was by no means unattractive.” And in 1493 the expedition of Christopher Columbus took time out of their wanton murdering to sight the mythical mermaid near what is now the Dominican Republic. As Columbus wrote in his diary: “The day before, when the Admiral was going to the Rio del Oro, he said he saw three mermaids who came quite high out of the water but were not as pretty as they are depicted, for somehow in the face they look like men.” And then they got back to the murdering and enslaving.

In reality, the admiral had likely seen a manatee (what Smith had seen is anyone’s guess, considering manatees don’t venture that far north). And indeed it was strange creatures like these, a group known tellingly as the sirenians that also includes dugongs, that explorers encountered as they made their way around the world. Sadly, they ended up driving the most incredible sirenian to extinction: Steller’s sea cow. At an astonishing 33 feet long and 24,000 pounds, it was 20 times heavier than the manatee. But because it was so large, it never needed to fear predators before humans. By the turn of the 19th century, it was gone.

Read more at Wired Science

Oct 15, 2014

Dinosaurs Were Heavy, Wet Breathers

The first ever reconstruction of how dinosaurs breathed finds that these long-extinct animals used each heavy, mucous-moistened breath to smell their surroundings and to cool their brains.

The study, published in the Anatomical Record, helps to explain why most non-avian dinosaurs had such long snouts. It also adds another dimension of life to these prehistoric animals, the last of which took its final breath around 65 million years ago.

Lead author Jason Bourke and his team used plant-eating Stegoceras as a model dinosaur since it had a particularly bony skull with fossilized bones in its nasal region still in place.

"The biggest difference between Stegoceras and us (in terms of breathing) is that it would have breathed more like a bird or reptile in that it probably took longer, deeper breaths," Bourke, an Ohio University doctoral student, told Discovery News.

Another major difference is that humans and other mammals have hairs in their nose to help block debris from going into the body. Dinosaurs did not have nose hairs, so they relied on something functional, but messy.

"Mucous was probably the number one defender of unwanted particles in the nose," Bourke said. "This mucous would be constantly flowing towards the nostril, creating a slow-moving conveyor belt that removed unwanted items from getting trapped in the nose. A good sneeze, now and then, would speed up the process."

The researchers analyzed dinosaur skull anatomy while also drawing from a branch of engineering called computational fluid dynamics that is commonly used in the aerospace industry and medicine. In this case, the scientists applied the process to modeling how air flows through the noses of modern day dinosaur relatives, such as ostriches and alligators, and then to Stegoceras.

Bourke explained that with each dinosaur breath, air would have moved from the nostrils through the internal structure of the dino's nasal passage. Some air entered a "dead end" spot at the back of the interior snout where much of the sense of smell was located. This is called the olfactory region.

The rest of the air would then exit the snout at the back of the throat and continue down the trachea to the lungs where gas exchange would occur, releasing oxygen and picking up carbon dioxide. Upon expiration, air would follow the same path, but in reverse.

Senior author Lawrence Witmer, a professor in the Ohio University Heritage of Osteopathic Medicine, explained that nasal "turbinates" -- scrolls of cartilage­ -- were key to understanding the process. Turbinates were likely in the front, respiratory part of the dinosaur's nasal cavity, increasing surface area and helping to direct air flow.

As for what the dinosaurs were doing with all of that air, co-author Ruger Porter said that it helped to cool blood, which circulated around the brain, essentially preventing the brain from cooking.

Porter said, "Overheating would be a major problem for most dinosaurs, simply because they were so huge. The hot blood from the body could easily fry the brain if physiological mechanisms aren’t in place to cool that blood down."

Seven-foot-long Stegoceras was relatively small for a dinosaur, but the researchers still think that brain cooling via breathing took place.

Read more at Discovery News

Trio of Huge Crocs Ruled Europe's Jurassic Waters

When dinosaurs were the apex land predators, a trio of huge crocodile-like animals muscled their way through European waters.

One of the three, Machimosaurus hugii, measured well over 30 feet long and is thought to have feasted on dinosaurs unlucky enough to have crossed the path of this beast, according to geoscientist Mark Young.

“There is a dinosaur femur with bite marks on it that resemble bite marks found on sea turtle shells,” Young, of both the University of Edinburgh and the University of Southampton, told Discovery News. “It isn’t clear whether Machimosaurus attacked dinosaurs, or would scavenge dead dinosaurs.”

Young and his colleagues analyzed the remains of Machimosaurus, which was a genus of teleosaurid, as well as its relatives. These animals were marine “crocodyliforms,” similar in appearance to today’s crocs.

A paper about them is published in the journal Royal Society Open Science.

Reviewing the fossils, the researchers determined that three different species of Machimosaurus lived during the Jurassic in what is now Europe:

Machimosaurus buffetauti- This is a newly described species. It measured around 20 feet long and lived in what are now France and Germany.

Machimosaurus mosae- According to Young, this croc was “adapted for living in turbulent coastal waters.” Specimens are only known from northern France. It was larger than M. buffetauti, and measured 26 feet long.

Machimosaurus hugii: This was the likely dino eater and the biggest of the bunch. “It was adapted for swimming in open seas,” Young said. “Specimens have been found in Portugal, Spain and Switzerland. It was the largest croc of the Jurassic and had the most bulbous teeth of any Machimosaurus species.”

The researchers described yet another similar species from the time, Machimosaurus nowackianus, but it wasn’t part of the European trio. This species lived in what would have been coastal Ethiopia. It proves that the crocs, as a collective genus, were a global force to reckon with during their lifetimes.

While the animals looked similar to today’s crocs, they are not closely related to them. The study therefore offers a snapshot of long-dead animals that were like the evolutionary pioneers of the alligator/croc family.

Young explained, “Teleosaurids, along with the dolphin-like metriorhynchids, were the first aquatic/marine radiation of crocs. This teleosaurid+metriorhynchid lineage went extinct in the Early Cretaceous.”

Read more at Discovery News

Largest Pottery Workshop of Greek Antiquity Found

German archeologists have discovered the largest industrial quarter of the Greek world, during an excavation in Sicily.

Streching for more than 3,200 feet, the craft district relied on about 80 kilns for the production of ceramics.

“The largest one is 17 feet in diameter, making it the biggest kiln ever found in a Greek city,” Martin Bentz, an archeologist at the University of Bonn, told Discovery News.

The finding was made in the periphery of Selinunte, on the southwest coast of Sicily.

The farthest west of the Greek colonies, known for its grand temples, Selinunte enjoyed centuries of prosperity before being reduced to rubble by the Carthaginians during the first Punic War.

Located along the river Cottone, now silted up, the industrial quarter operated inside the city walls.

“It was separated from the rest of the city by an non-built-up area so to protect the inhabitants from fire danger, smell and noise,” Bentz said.

Bentz’s team made long trenches to reach the end of the workshop and noticed it’s one big homogeneous construction built on four terraces on the slopes of the city hill.

The industrial quarter featured a central courtyard for drying the products before firing, two large working and firing areas and, at the end toward the city, a shop to sell the products.

“The whole construction is more than 3,900 square feet, by far the largest workshop we know in the Greek world,” Bentz said.

The quarter and the workshop were founded around 550 B.C. At that time, the production focused on small artistic terracotta statuettes.

Read more at Discovery News

Four California Faults Are Ready to Rupture

With several faults slicing through the San Francisco Bay Area, forecasting the next deadly earthquake becomes a question of when and where, not if.

Now researchers propose that four faults have built up enough seismic strain (stored energy) to unleash destructive earthquakes, according to a study published today (Oct. 13) in the Bulletin of the Seismological Society of America.

The quartet includes the Hayward Fault, the Rodgers Creek Fault, the Green Valley Fault and the Calaveras Fault. While all are smaller pieces of California's San Andreas Fault system, which is more than 800 miles (1,300 kilometers) long, the four faults are a serious threat because they directly underlie cities.

"The Hayward Fault is just right in the heart of where people live, and the most buildings and the most infrastructure," said Jim Lienkaemper, lead study author and a research geophysicist at the U.S. Geological Survey's Earthquake Science Center in Menlo Park, California. "But it's not just one fault, it's the whole shopping basket. If you are in the middle of the Bay Area, you are near a whole lot of faults, and I'm concerned about all of them."

Lienkaemper and his colleagues gauged the potential for destructive earthquakes by monitoring tiny surface shifts along California faults. Certain faults are in constant motion, creeping steadily by less than 0.4 inches (1 centimeter) each year. These slow movements add up over time, cracking sidewalk curbs and buildings. They also serve as clues to what's happening deep below ground, where earthquakes strike.

"If you figure out where faults are creeping, it tells you where they're locked and how much they're locked," Lienkaemper told Live Science.

Fault creep varies, with some faults sliding at a snail's pace and others barely budging. Models suggest that the diversity comes from locked zones that are 3 to 6 miles (5 to 10 km) below the surface, where the fault is stuck instead of sliding. For example, the relatively fast-creeping southern Hayward Fault is only about 40 percent locked, on average, while the slow-creeping Rodgers Creek Fault is 89 percent locked, the study reports. When these locked areas build up a critical amount of strain, they break apart in an earthquake.

Lienkaemper and his co-author estimated a fault's future earthquake potential by combining creep measurements with mathematical fault models and other regional data, such as the time since the last earthquake.

The Hayward Fault has banked enough energy for a magnitude-6.8 earthquake, according to the study. The Rodgers Creek Fault could trigger a magnitude-7.1 earthquake, and the Green Valley Fault also has the potential to unleash a magnitude-7.1 shaker. The Northern Calaveras Fault is set for a magnitude-6.8 temblor.

Of all Bay Area faults, the Hayward Fault is most likely to spawn a damaging earthquake in the next 30 years, scientists think. Its 1868 earthquake was called the Big One until the great 1906 San Francisco quake came along. The Hayward Fault has ruptured about every 140 years for its previous five large earthquakes. The probability of a magnitude-6.7 earthquake on the Hayward Fault is 30 percent in the next 30 years.

Read more at Discovery News

'Exo-Uranus' Discovered Around Distant Star

For the first time, astronomers have announced the discovery of an exoplanet that they believe could resemble our solar system’s ‘ice giants’ Uranus or Neptune.

In the study, published in the The Astrophysical Journal, Radek Poleski and his team from Ohio State University identified the alien world orbiting a star in a binary system some 25,000 light-years away in the direction of Sagittarius. The binary system is composed of a star approximately two-thirds the mass of our sun, whereas its stellar partner is only one-sixth of a solar mass. The ‘exo-Uranus’ orbits the larger star.

However, at first glance, this new world seems anything but Uranus-like (or, indeed, Neptune-like), it’s actually four times more massive than the planet that we know and love. But the key here is that it has a Uranus-like orbit, a characteristic that could make it the first exoplanet to possess a Uranus-like composition — though this cannot be tested as the world is too distant for us to study its chemical makeup.

Both Uranus and Neptune are distinct from the other two gas giants in our solar system (Jupiter and Saturn) in that their thick atmospheres are loaded with methane ices; a factor that gives these two planets their blueish hue. Located further away from the sun, it seems that their orbital distance has allowed Uranus and Neptune’s icy evolution.

“Nobody knows for sure why Uranus and Neptune are located on the outskirts of our solar system, when our models suggest that they should have formed closer to the sun,” said Andrew Gould, also of Ohio State and co-investigator. “One idea is that they did form much closer, but were jostled around by Jupiter and Saturn and knocked farther out.”

This distant exo-Uranus was discovered when the world orbited in front of its star. In doing so, the world’s gravitational field, which warps space-time, created a ‘microlens’ event where the star’s light became focused and brightened from Earth’s perspective.

Microlensing events happen purely by chance and can happen anywhere in the galaxy, so we have networks of observatories around the globe that are constantly surveying the whole sky in the hope of spotting these transient brightenings. In this case, the 1.3-meter Warsaw Telescope at Las Campanas Observatory in Chile of the international Optical Gravitational Lensing Experiment (OGLE) identified two separate microlensing events — one in 2008 that revealed the presence of the main star and hinted at the presence of a planet, and a second event in 2010 that confirmed the planet and the presence of a smaller binary partner.

By combining the two microlensing observations, the team was able to measure the two stars’ masses and derive the exoplanet’s mass and orbital distance.

Interestingly, it’s the presence of the smaller binary partner that may help explain the origin of this exo-Uranus and, in turn, may also offer clues as to how our Uranus and Neptune came to migrate to the far-flung orbits they occupy today.

“Maybe the existence of this Uranus-like planet is connected to interference from the second star,” said Gould. “Maybe you need some kind of jostling to make planets like Uranus and Neptune.”

Read more at Discovery News

Oct 14, 2014

Fossilized Bladder Stone Found in Medieval Cemetery

It may look innocuous now, but this little stone may have killed someone 700 years ago.

The rough, kidney-shaped object was found in a medieval cemetery in Poland, and a new analysis has revealed it is actually a rather large bladder stone.

The stone was discovered in GdaƄsk, a city on the Baltic coast of northern Poland, where archaeological excavations in 2001 uncovered a medieval burial ground that contained a thousand graves. Since this cemetery was used for about 800 years, the dead were not left to rest in peace; some corpses were exhumed and regrouped with other gravemates to make way for new bodies, according to the researchers, who reported the find in the journal PLOS ONE this month.

The stone was found among the skeletons of four badly preserved bodies: a female between 20 and 39 years old, an older male between 40 and 55 years old, a teenager and a fetus (the sex was not determined). The researchers don't have a precise date for the burial of the corpses, but they think these bodies were interred between the mid-10th century and the mid-14th century.

The mass is about 1.5 inches (3.9 centimeters) long and 0.5 inches (1.25 cm) thick, and it weights about 0.25 ounces (6.87 g). When the researchers cut into the brownish stone with a diamond blade, they saw that it had yellowish concentric layers inside, characteristic of bladder stones.

The researchers think the stone may have come from any one of the grave's occupants, except the fetus. And whoever it belonged to was rather unlucky. The rough, porous edges of the stone suggest that "a very aggressive bacterial inflammation" developed in the last stages of the stone's formation, which was likely the cause of death, the researchers wrote.

It's not the oldest — or the biggest — ancient bladder stone to be found. More than a century ago, Egyptologist Grafton Elliot Smith found what might be the oldest bladder stone among the remains of the pelvic bones of a teenage boy who was buried in ancient Egypt around 4800 B.C. In 2008, researchers reported the discovery of a giant bladder stone — measuring nearly 3 inches (7.5 cm) across — in the pelvis of a 19th century natural mummy.

Bladder stones form when organic compounds and inorganic crystals in urine compress into hard masses in the bladder. Some stones might go unnoticed, but sometimes they can irritate the bladder wall or block the flow of urine and cause painful urination and abdominal pain. Sometimes larger stones need to be broken up into smaller pieces or removed through surgery to prevent infections or further complications. Doctors have experimented with medical treatments for urinary stones for centuries. As far back as 2,000 years ago, the ancient Greeks used a procedure known as a lithotomy to surgically cut through the body in an attempt to remove stones, according to a history of the bladder stone published in the Journal of the Royal Society of Medicine.

Read more at Discovery News

Ancient Sailors Made Sacrifices on Ships

Ancient Mediterranean sailors performed religious ceremonies and sacrifices on board their ships, according to new findings from a 2,000-year-old shipwreck.

Using a deep sea mini-submarine, archaeologists of the Sicilian Sea Superintendency and Global Underwater Explorers (GUE) divers found the wreck and its cargo of jars at a depth of 420 feet in the waters of Sicily's Aeolian islands.

In the area of the bow -- a portion of the wooden hull is still preserved -- the archaeologists found a terracotta incense burner called thymiaterion. Consisting of a large bowl supported by a column, the thymiaterion had a base embellished with stylized sea waves. A Greek inscription of three letters (ETH) was also found on the base.

"The object confirms historical accounts of sacrifices and rituals performed at sea to protect the voyages," Sebastiano Tusa, Sicily's Superintendent of the Sea Office, told Discovery News.

Tusa and the GUE divers also found many large terracotta jars, called amphora, piled on the sea floor. These jars were used as shipping containers and carried trade products such as honey, olive oil, wine and fish sauce.

Among the jars, divers found bowls and cylindrical vases. But the incense burner remains the most important find.

"There are only a handful of other incense burners that have come from wrecks throughout the entire Mediterranean," Aaron Brody, associate professor of bible and archaeology and director of the Bade Museum at Pacific School of Religion, Berkeley, Calif., told Discovery News.

An expert in maritime religion, Brody explained that religious rites were performed while a ship left port and when it entered a harbor safely.

But rituals were also officiated in between, during the navigation, passing landmarks, or in times of distress.

"Their purpose was to either appease or thank gods who controlled the winds or who could aid in proper navigation, or when auspicious natural features were within sight, like mountain peaks or landmarks dedicated to deities," Brody said.

Typically, the rituals took place at sacred locations aboard ships, often in the prow and or the stern, and involved animal sacrifices, prayer, offering, libation, or vow.

"The presence of the incense burner aboard the vessel suggests rites that were easy to fulfill at any time since incense is light and portable," Brody said.

Read more at Discovery News

Ancient Cult Complex Discovered in Israel

A massive cult complex, dating back about 3,300 years, has been discovered at the site of Tel Burna in Israel.

While archaeologists have not fully excavated the cult complex, they can tell it was quite large, as the courtyard alone was 52 by 52 feet (16 by 16 meters). Inside the complex, researchers discovered three connected cups, fragments of facemasks, massive jars that are almost as big as a person and burnt animal bones that may indicate sacrificial rituals.

The archaeologists said they aren't sure who was worshipped at the complex, though Baal, the Canaanite storm god, is a possibility. "The letters of Ugarit [an ancient site in modern-day Syria] suggest that of the Canaanite pantheon, Baal, the Canaanite storm god, would have been the most likely candidate," Itzhaq Shai, a professor at Ariel University who is directing a research project at Tel Burna, told Live Science in an email.

The researchers said they can't rule out that a female deity, such as the ancient war goddess Anat, was worshipped there, Shai said.

Cultic discoveries

The artifacts include fragments of two masks. "The burna mask fragments, both of noses, are quite interesting, because they are quite large, although as seen in [a photo], they were clearly meant to be worn," Shai said.

"It is difficult to determine exactly who the masks are depicting and whether it is a specific image. In general, masks are known to have been used in cultic ceremonies and processions."

The three connected cups, which were found in the cultic complex, were likely imported from Cyprus, the researchers say. The artifacts' use remains a mystery. "In the past, joint vessels similar in concept as the one found here have been considered as cultic objects," said Shai.

Dvory Namdar, of Hebrew University, is currently analyzing the walls of the vessels to determine what was put in them, something that may shed light on their purpose Shai said. "Residue analysis is currently being conducted in order to further understand what this vessel may have been used for," said Shai.

Giant vessels, scarabs and more …

The researchers also found massive "pithoi" vessels (large storage jars), some almost as big as a person. "Along the eastern edge of the exposed area of the building, a row of sunken pithoi, with several smaller vessels found inside of them, were found," said Shai. Two of the vessels were imported from Cyprus, as indicated by their design.

"The pithoi were likely used as storage for tithes brought to the cultic complex, although this is also being further analyzed through residue analysis." A tithe, in this instance, would be goods given to the cultic complex by those who used or lived near it.

The complex yielded many other finds, including a cylinder-shaped seal, goblets, chalices, broken figurines that look part-human and part-animal, and even a scarab, an artifact with an Egyptian hieroglyphic inscription on it.

Feasting, sacrifices and ceremonies


While more analysis is needed, the discoveries shed light on some of the activities that took place in the cult complex.

"From the finds within the building, we can reconstruct the occurrence of feasts, indicated by several goblets and a large amount of animal bones. Some of these animal bones are burnt, probably indicating their use in some sacrificial activity," said Shai.

Read more at Discovery News

Moon Tethys 'Hangs' Off Saturn's Rings

In a stunning photograph beamed back to Earth from NASA’s Cassini spacecraft, one of Saturn’s moons appears to ‘hang’ off the gas giant’s rings like a water droplet.

The icy moon Tethys is approximately 660 miles wide and is composed of similar material as the rings it is orbiting behind. Cassini snapped the moon with its narrow-angle camera on July 14 at a distance of 1.1 million miles.

In the foreground, two of Saturn’s rings — the A and F rings — overlap Tethys from Cassini’s perspective. The F ring is Saturn’s outermost ring and is separated from the A ring by a gap of 1,900 miles — known as the Roche Division. Embedded in the A ring, overlapping Tethys, is a very thin 26 mile separation called the Keeler Gap that is kept clear by the tiny moon Daphnis, which is out of shot.

Although the A ring seems to overlap Tethys, the moon actually orbits Saturn nearly 100,000 miles higher than the ring.

Cassini has been orbiting Saturn for over ten years, transforming our view of the gas giant, its rings and extensive family of moons. Sadly, as the spacecraft runs low on thruster fuel, mission scientists are beginning to plan for mission end. More details on Cassini’s “Grand Finale” mission can be read here.

From Discovery News

Volcanoes Erupted 'Recently' on the Moon

A region of young volcanic deposits imaged by the LROC near the crater Maskelyne.
When you think of volcanic activity across the solar system you probably picture some of Earth’s many volcanoes, as well as those covering Jupiter’s moon Io, the enormous (but very extinct) volcanoes of Mars, and perhaps even the ice volcanoes that are thought to exist on Saturn’s moon Titan.

But there was a time early in the solar system’s history when lava poured from volcanic vents on many other worlds as well, such as the innermost planet Mercury and even our own moon.

It’s traditionally been thought that the moon’s volcanoes went cold quite a while back — between 1 and 1.5 billion years ago. But recent discoveries by NASA’s Lunar Reconnaissance Orbiter show some spots that may have experienced volcanic eruptions much later — some as recent as 33 million years ago!

Now 33 million years may not sound very “recent” to us but on a geologic time scale it’s like it happened just last week.

Small areas of what appear to be recent basaltic lava deposits have been identified in images acquired by the Lunar Reconnaissance Orbiter Camera (LROC) on the moon’s near side. These “irregular mare patches,” or IMPs, contain rough and smooth surfaces with few craters larger than 20 meters (65 feet), indicating a young age.

70 IMPs have thus far been identified, the best-known of which (and first discovered) is one named Ina, seen by Apollo 15 from lunar orbit. 2 km (1.25 miles) across, Ina was unlike any other region seen by Apollo astronauts and was originally thought to be an irregularly-collapsed caldera.

An oblique view of the 2-km-wide Ina from LRO. The raised smooth mounds and lower rough depressions are evident here.
Now, after five years of observations by LRO, scientists know that Ina is not just a singular anomaly but rather one of many IMPs that point to a much longer span of lunar volcanism — and possibly a warmer lunar interior — than what had previously been estimated.

Read more at Discovery News

Oct 13, 2014

Tailored flexible illusion coatings hide objects from detection

Developing the cloak of invisibility would be wonderful, but sometimes simply making an object appear to be something else will do the trick, according to Penn State electrical engineers.

"Previous attempts at cloaking using a single metasurface layer were restricted to very small-sized objects," said Zhi Hao Jiang, postdoctoral fellow in electrical engineering, Penn State. "Also, the act of cloaking would prevent an enclosed antenna or sensor from communicating with the outside world."

Jiang and Douglas H. Werner, John L. and Genevieve H. McCain Chair Professor of Electrical Engineering, developed a metamaterial coating with a negligible thickness that allows coated objects to function normally while appearing as something other than what they really are, or even completely disappearing. They report their research in Advanced Functional Materials.

The researchers employ what they call "illusion coatings," coatings made up of a thin flexible substrate with copper patterns designed to create the desired result. They can take a practical size metal antenna or sensor, coat it with the patterned film and when the device is probed by a radio frequency source, the scattering signature of the enclosed object will appear to be that of a prescribed dielectric material like silicon or Teflon. Conversely, with the proper pattern, they can coat a dielectric and it will scatter electromagnetic waves the same as if it were a metal object.

"The demonstrated illusion/cloaking coating is a lightweight two-dimensional metasurface, not a bulky three-dimensional metasurface," said Werner.

The researchers take the object they want cloaked and surround it with a spacer, either air or foam. They then apply the ultrathin layer of dielectric with copper patterning designed for the wavelengths they wish to cloak. In this way, antennae and sensors could be made invisible or deceptive to remote inspection.

Another application of this material would be to protect objects from other emitting objects nearby while still allowing electromagnetic communication between them. This was not possible with the conventional transformation optics-based cloaking method because the cloaking mechanism electromagnetically blocked the cloaked object from the outside, but this new coating allows the object surrounded to continue working while being protected. In an array of antennae, for example, interference from the nearby antennas can be suppressed.

The metasurface coating consists of a series of copper, geometric patterns placed on a flexible substrate using standard lithographic methods currently used to create printed circuit boards. Each illusion coating must be designed for the specific application, but the designs are optimized mathematically. This method of manufacture is low cost and well established.

Another advantage of this method is that it works not only for direct hits by radio frequency waves incident normally on the coated object, but also continues to operate properly within a 20 degree field of view, making it a better angle-tolerant shield than previous attempts that employed bulky metamaterials. Currently, the metasurface coatings only work on narrow bands of the spectrum for any application, but can be adapted to work in other bands of the electromagnetic spectrum including the visible spectrum.

Read more at Science Daily

First observation of atomic diffusion inside bulk material

Researchers at the Department of Energy's Oak Ridge National Laboratory have obtained the first direct observations of atomic diffusion inside a bulk material. The research, which could be used to give unprecedented insight into the lifespan and properties of new materials, is published in the journal Physical Review Letters.

"This is the first time that anyone has directly imaged single dopant atoms moving around inside a material," said Rohan Mishra of Vanderbilt University who is also a visiting scientist in ORNL's Materials Science and Technology Division.

Semiconductors, which form the basis of modern electronics, are "doped" by adding a small number of impure atoms to tune their properties for specific applications. The study of the dopant atoms and how they move or "diffuse" inside a host lattice is a fundamental issue in materials research.

Traditionally, diffusion of atoms has been studied through indirect macroscopic methods or through theoretical calculations. Diffusion of single atoms has previously been directly observed only on the surface of materials.

The experiment also allowed the researchers to test a surprising prediction: Theory-based calculations for dopant motion in aluminum nitride predicted faster diffusion for cerium atoms than for manganese atoms. This prediction is surprising as cerium atoms are larger than manganese atoms.

"It's completely counterintuitive that a bigger, heavier atom would move faster than a smaller, lighter atom," said the Material Science and Technology Division's Andrew Lupini, a coauthor of the paper.

In the study, the researchers used a scanning transmission electron microscope to observe the diffusion processes of cerium and manganese dopant atoms. The images they captured showed that the larger cerium atoms readily diffused through the material, while the smaller manganese atoms remained fixed in place.

The team's work could be directly applied in basic material design and technologies such as energy-saving LED lights where dopants can affect color and atom movement can determine the failure modes.

"Diffusion governs how dopants get inside a material and how they move," said Lupini. "Our study gives a strategy for choosing which dopants will lead to a longer device lifetime."

Read more at Science Daily

Learn to Make Stone-Age Tools to Help Study the Origins of Language

Scientists believe that Stone Age toolmaking might have links to the development of language.
Our ancestors started making tools at around the same time they learned to speak, and some scientists believe that the two skills share the same neurological pathways. To test this hypothesis, a team of researchers is going to monitor the brains of modern people as they learn how to make Stone Age-style hand axes.

The study, led by archaeologist Dietrich Stout of Emory University in Atlanta, will train 20 people for 100 hours each in a technique called knapping, where the toolmaker strikes a piece of crystalline material like flint or obsidian with “hammerstone” made from quartzite. (This video shows the basics.) Stout and his co-investigators will use several methods to monitor how tool making overlaps with language. One of the most important will be MRI scans.

The basic hypothesis, he says, is that the way our brains approach physical tasks—like making a hand axe—has a syntax analogous to the way our brains approach language. To establish a base line for how language activates the brain, the researchers will give their subjects MRIs while they listen to a story. Then, they’ll take MRIs of their brains as they learn knapping, and observe whether the steps of tool making (closing a hand around a rock, banging it against another rock) activate the same areas as parts of language (translating sounds into words, and words into sentences). They’ll also use eye-tracking tests, individual measurements for planning and working memory, and video analysis of tool-making sequences.

There won’t be many restrictions on who is eligible for enrolling in the study, only that they be 18-50 years old, have no history of neurological illness, and no prior experience making stone tools (Sorry, Brendan Frasier). Additionally, they need to be right handed, Stout said, “Because things get complicated in the brain with variation in handedness.” If you meet these criteria, and want to spend the next three years making hand axes, you can apply to join the study.

Michael Ullman, a neuroscientist at Georgetown University who studies links between language development and motor skills, says that the team’s hypothesis linking tools and language is plausible. But, he has doubts about their methodology. “Why are they comparing someone’s learning process with tool making with the use of a language they already know and learned as a child?,” he wonders. He says the study’s co-investigators could do better by comparing learning to make tools to learning a new language (i.e, a second/foreign language). Ullman also questioned the team’s decision to have the subjects learn to make stone age tools, saying that it felt “a bit gimmicky,” as opposed to something more modern.

Read more at Wired Science