Jan 17, 2015

East Africa Tries to Stem Albino Magic Murders

The East African country of Tanzania has reportedly banned witch doctors in an effort to prevent further witchcraft-related murders of albinos.

According to a story reported by Agence France-Presse, “The ban follows the kidnapping last month of a four-year-old girl by men armed with machetes, who took her from her home in the northern Mwanza region. Police have since arrested 15 people, including the girl’s father and two uncles, but she remains missing. ‘These so-called witches bear responsibility for the attacks against albinos,’ interior ministry spokesman Isaac Nantanga told AFP Wednesday.”

In Tanzania and Burundi at least 50 albinos have been murdered for their body parts in recent years according to a 2010 Red Cross report. In November 2009, four people were arrested and sentenced to death in northern Tanzania for killing an albino man to harvest his body parts.

A month earlier, albino hunters beheaded a 10-year-old boy and hacked off his leg. In May of last year two witch doctors were arrested in connection with the death of an albino woman who was murdered for her body parts.

Throughout Africa witch doctors are consulted not only for healing diseases, but also for placing (or removing) magic curses or bringing luck in love or business. The belief and practice of using body parts for magical ritual or benefit is called muti. Muti murders are particularly brutal, with knives and machetes used to cut and hack off limbs, breasts, and other body parts from their living victims.

Laws Against Witchcraft

Some of the news headlines about Tanzania’s effort are misleading; for example AFP wrote that “Tanzania Bans Witch Doctors in Attempt to End Albino Killings.” Sensational headlines aside, as a practical matter there is no chance that witchcraft will be effectively abolished in Tanzania or elsewhere in Africa.

It’s been tried before: Colonial governments, and the British Empire in particular, instituted various anti-witchcraft laws in the 19th and 20th centuries. By passing those laws the governments did not officially endorse the reality of magic or witchcraft but instead implemented them to curb accusations of witchcraft.

Tanzania’s neighbor Zambia, for example, passed a law known as the Witchcraft Suppression Act of 1957, which criminalized “on the advice of any witchdoctor, witch-finder or other person or on the ground of any pretended knowledge of witchcraft, uses or causes to be put into operation any means or process which, in accordance with such advice or his own belief, is calculated to injure or damage any person or thing.”

This would of course include the harming or killing of albinos for their body parts to be used in magic spells.

Despite such efforts, attempts by African countries to outlaw witchcraft have historically failed. Gerrie ter Haar, a professor of Religion, Human Rights and Social Change, writing in “Imagining Evil: Witchcraft Beliefs and Accusations in Contemporary Africa,” notes that “a law that makes witchcraft a criminal act punishable by the state…would seriously undermine the integrity of the law. Whereas the law properly operates on the basis of written rules and strict procedures that follow international standards, witchcraft accusations are generally based on gossip and hearsay that lacks actual proof since it is based on belief, and not on evidence of a type required in court. Whereas law enforcement is fully institutionalized, witchcraft accusations operate beyond any institutional control…. The Witchcraft Suppression Act that is still in force in South Africa appears to have done nothing to reduce the widespread fear of witchcraft.”

“Most of the literature on the efficacy of Western education for combating witchcraft belief holds that insight into the natural causes of diseases and other misfortunes will show Africans that their fear of witchcraft is unfounded.”

South African Professor of Theology and Religious Studies Selaelo Thias Kgatla, writing in the same book, explains that legislation against witchcraft is ineffective because it fails to address the root of the problem.

In other words as long as people believe that the bad things that happen to them are caused by enemies’ black magic instead of random chance or bad luck, they will seek magical protections and remedies against them — including, sometimes, albino body parts.

The vast majority of witch doctors and traditional healers throughout Africa are not involved in muti murders, though they routinely offer magical services to attract luck or dispel curses.

Read more at Discovery News

Tongan Volcano Creates New Island

A Tongan volcano has created a substantial new island since it began erupting last month, spewing out huge volumes of rock and dense ash that has killed nearby vegetation, officials said on Friday.

The volcano, about 65 kilometers (40 miles) northwest of the South Pacific nation's capital Nuku'alofa, rumbled to life on December 20 for the first time in five years, the Lands and Natural Resources Ministry said.

It said the volcano was erupting from two vents, one on the uninhabited island of Hunga Ha'apai and the other underwater about 100 meters (328 feet) offshore.

The ministry said experts took a boat trip to view the eruption on Thursday and confirmed it had transformed the local landscape.

"The new island is more than one kilometer (0.6 mile) wide, two kilometers (1.2 miles) long and about 100 meters (328 feet) high," it said in a statement.

"During our observations the volcano was erupting about every five minutes to a height of about 400 meters (1,312 feet), accompanied by some large rocks... as the ash is very wet, most is being deposited close to the vent, building up the new island."

It said ash and acidic rain was deluging an area 10 kilometers (6.2 miles) around the volcano, adding: "Leaves on trees on Hunga Tonga and Hunga Ha'apai have died, probably caused by volcanic ash and gases."

A number of international flights were cancelled earlier this week amid concerns about the volcano's ash plume but they resumed on Wednesday, with authorities saying debris from the eruption was not being thrown high into the atmosphere.

Read more at Discovery News

Humans are Nearly Halfway to Wrecking the Planet

Humans are nearly halfway to damaging the environment so gravely that the Earth will cease to be a “safe operating space” for our species, reports a just-published article in the journal Science.

The paper, which is the work of an international team of 18 scientists headed by Will Steffen of the Stockholm Resilience Centre and Australian National University in Canberra, reports that four of nine “planetary boundaries” have been crossed as the result of human activity, meaning that we’re in big trouble in those areas.

The crossed boundaries include:

  • Climate change
  • The rate of loss of biological diversity
  • Deforestation and other changes in the land system
  • Alteration of the natural global nitrogen and phosphorus cycles by agriculture and industrial processes, which is threatening aquatic life and causing massive algae blooms in lakes and oceans.

In a video on the Washington Post website, Stockholm Resilience Centre executive director Johan Rockström explained that these are “critical biophysical boundaries that we need to stay within to avoid unacceptable environmental change, with serious, potentially disastrous consequences for society,”

Of the crossed boundaries, the scientists say that climate change and loss of biological diversity — also called “biosphere integrity” — are the two most critical.

The remaining boundaries that humans haven’t yet crossed include:

  • Stratospheric ozone depletion
  • Chemical pollution
  • Ocean acidification
  • Freshwater consumption and the hydrological cycle
  • Human emission of atmospheric aerosols, which are tiny dust particles that affect the climate.
Read more at Discovery News

At Least Two More Planets May Exist Beyond Pluto

A new study suggests that at least two more planets are circling the sun far beyond Pluto’s orbit.

The analysis is based on calculations of bodies located well past Neptune, regions of space that include the Kuiper Belt, the scattered disk and the Oort cloud.

Instead of randomly flying through space, 12 of these so-called “extreme trans-Neptunian objects” (ETNO) show some unexpected symmetry.

“This excess of objects with unexpected orbital parameters makes us believe that some invisible forces are altering the distribution of the orbital elements of the ETNO,” Carlos de la Fuente Marcos, with the Complutense University of Madrid, said in a press release.

“We consider that the most probable explanation is that other unknown planets exist beyond Neptune and Pluto,” he said.

The study was based on calculations of the gravitational influences a  large object would have on smaller, distant bodies.

“If it is confirmed, our results may be truly revolutionary for astronomy,” de la Fuente Marcos said.

The research is published in the Monthly Notices of the Royal Astronomical Society.

From Discovery News

Jan 16, 2015

Lost Beagle Mars Lander Spotted by NASA Spacecraft

The Beagle has landed, new images taken by a sharp-eyed satellite orbiting Mars show, more than a decade after contact with the U.K.-built spacecraft was lost during the probe’s descent to the planet's surface.

Beagle 2 was released by the European Space Agency’s Mars Express orbiter on Dec. 23, 2003, and programmed to touch down in Isidis Planitia, an impact basin close to the Martian equator.

It was never heard from again.

"To be frank, I had all but given up hope of ever knowing what happened to Beagle 2," Mark Sims, a former mission manager with the University of Leicester, said in a statement.

Images taken by NASA's Mars Reconnaissance Orbiter (MRO) and released on Friday show that Beagle 2 did indeed make it to the planet's surface and apparently at least partially deployed its solar panels.

"Whether all the panels have been opened up or not has yet to be determined by the Beagle team," planetary geologist Tim Parker, with NASA’s Jet Propulsion Laboratory in Pasadena, Calif., said in a NASA interview.

The lost lander appeared as bright streaks in two images, confirmation that the object actually was something on the ground and not an optical artifact from a cosmic ray striking the camera's electronic eye.

Analysis of a third image was then used to distinguish glints of light reflecting from different angles. Working with the Beagle 2 team, Parker and colleagues were then able to identify what appears to be the lander itself in a partially deployed configuration and what is believed to be the rear cover with its drogue chute still attached. Beagle 2's main parachute is nearby.

Read more at Discovery News

New Species of Legless Amphibian Found in Cambodia

A new species of legless amphibian resembling a giant earthworm or a snake has been discovered in a remote but threatened area of Cambodian rainforest, conservationists said on Friday.

The grey-brown creature -- Ichthyophis cardamomensis -- was found in Cambodia's southwest Cardamom Mountains, an area under threat from habitat loss, according to Fauna and Flora International (FFI).

The new species is often mistaken for a snake, with larger species known to grow up to 1.5 metres (nearly five feet) in length, FFI said.

It was confirmed by scientists earlier this month according to leading Cambodian FFI herpetologist Neang Thy.

"These discoveries are important to demonstrate that much of Cambodia's biodiversity remains unknown and unstudied by science, and many more areas need to be searched," Thy, who has been researching amphibians and reptiles since 2003, told AFP.

The creature is caecilian -- an order of amphibians that look like snakes or earthworms and are generally found underground.

Once a stronghold of the toppled Khmer Rouge regime, the bio-diverse Cardamom Mountains are home to an array of rare species, including the Asian elephant, but the area faces widespread deforestation.

Conservationists warn that illegal logging and other habitat destruction could mean new species become extinct shortly after discovery.

From Discovery News

The Best Bet for Alien Life May Be in Planetary Systems Very Different From Ours

Illustration of the planetary system around an M dwarf called Kepler-42.
In the hunt for extraterrestrial life, scientists started by searching for a world orbiting a star just like the sun. After all, the steady warmth of that glowing yellow ball in the sky makes life on Earth possible.

But as astronomers continue to discover thousands of planets, they’re realizing that if (or when) we find signs of extraterrestrial life, chances are good that those aliens will orbit a star quite different from the sun—one that’s redder, cooler, and at a fraction of the sun’s size and mass. So in the quest for otherworldly life, many astronomers have set their sights on these small stars, known as red dwarfs or M dwarfs.

At first, planet-hunting astronomers didn’t care so much about M dwarfs. After the first planet outside the solar system was discovered in 1995, scientists began hunting for a true Earth twin: a rocky planet like Earth with an orbit like ours around a sun-like star. Indeed, the search for that kind of system drove astronomers through most of the 2000s, says astronomer Phil Muirhead of Boston University.

But then astronomers realized that it might be technically easier to find planets around M dwarfs. Detecting another planet is really hard, and scientists rely on two main methods. In the first, they look for a drop in a star’s brightness when a planet passes in front of it. In the second, astronomers measure the slight wobble of a star, caused by the gentle gravitational tug of an orbiting planet. With both of these techniques, the signal is stronger and easier to detect for a planet orbiting an M dwarf. A planet around an M dwarf also orbits more frequently, increasing the chances that astronomers will spot it.

M dwarfs got a big boost from the Kepler space telescope, which launched in 2008. By staring at small patch of the sky, the telescope searches for suddenly dimming stars when a planet passes in front of them. In doing so, the spacecraft discovered a glut of planets—more than 1,000 at the latest count—it found a lot of planets around M dwarfs. “Kepler changed everything,” Muirhead said. Because M-dwarf systems are easier to find, the bounty of such planets is at least partly due to a selection effect. But, as Muirhead points out, Kepler is also designed to find Earth-sized planets around sun-like stars, and the numbers so far suggest that M-dwarfs may offer the best odds for finding life.

“By sheer luck you would be more likely to find a potentially habitable planet around an M dwarf than a star like the sun,” said astronomer Courtney Dressing of Harvard. She led an analysis to estimate how many Earth-sized planets—which she defined as those with radii ranging from one to one-and-a-half times Earth’s radius—orbit M dwarfs in the habitable zone, the region around the star where liquid water can exist on the planet’s surface. According to her latest calculations, one in four M dwarfs hosts such a planet.

That’s higher than the estimated number of Earth-sized planets around a sun-like star, she says. For example, an analysis by astronomer Erik Petigura of UC Berkeley suggests that fewer than 10 percent of sun-like stars have a planet with a radius between one and two times that of Earth’s.

This illustration shows Kepler-186f, the first rocky planet found in a star’s habitable zone. Its star is an M dwarf.
M dwarfs have another thing going for them. They’re the most common star in the galaxy, comprising an estimated 75 percent of the Milky Way’s hundreds of billions of stars. If Dressing’s estimates are right, then our galaxy could be teeming with 100 billion Earth-sized planets in their stars’ habitable zones.

To be sure, these estimates have lots of limitations. They depend on what you mean by the habitable zone, which isn’t well defined. Generally, the habitable zone is where it’s not too hot or too cold for liquid water to exist. But there are countless considerations, such as how well a planet’s atmosphere can retain water. With a more generous definition that widens the habitable zone, Petigura’s numbers for Earth-sized planets around a sun-like star go up to 22 percent or more. Likewise, Dressing’s numbers could also go up.

Astronomers were initially skeptical of M-dwarf systems because they thought a planet couldn’t be habitable near this kind of star. For one, M dwarfs are more active, especially during within the first billion years of its life. They may bombard a planet with life-killing ultraviolet radiation. They can spew powerful stellar flares that would strip a planet of its atmosphere.

And because a planet will tend to orbit close to an M dwarf, the star’s gravity can alter the planet’s rotation around its axis. When such a planet is tidally locked, as such a scenario is called, part of the planet may see eternal daylight while another part sees eternal night. The bright side would be fried while the dark side would freeze—hardly a hospitable situation for life.

But none of these are settled issues, and some studies suggest they may not be as big of a problem as previously thought, says astronomer Aomawa Shields of UCLA. For example, habitability may depend on specific types and frequency of flares, which aren’t well understood yet. Computer models have also shown that an atmosphere can help distribute heat, preventing the dark side of a planet from freezing over.

In some respects, a planet around an M-dwarf may actually be more hospitable. A habitable planet would likely have lots of water and ice, and using computer simulations of climate, Shields analyzed how an M dwarf’s starlight interacts with the planet’s atmosphere and surface ice. An M dwarf produces more infrared radiation than a sun-like star, and because an orbiting planet’s atmosphere and ice are good at absorbing infrared light, the planet would be harder to freeze than one around a sun-like star. And if it does freeze over, Shields explains, it thaws more easily.

This kind of stable climate would give burgeoning life more time to evolve without being disturbed by rapid cooling or heating. Still, she adds, a frozen planet doesn’t necessarily preclude life. Earth, after all, may have gone through such a “snowball Earth” phase more than about 600 million years ago.

Read more at Wired Science

The Beautiful Octopus Whose Sex Is All About Dismemberment

What are you doing in that shell, little octopus? You don’t belong in a shell. Go home. You’re drunk.
In Jules Verne’s 20,000 Leagues Under the Sea, the crew of the Nautilus takes a break from going for swims and pissing off native islanders to admire an armada of strange beasts floating along the surface, swimming backward by blasting water out of their bodies. “Six of their eight tentacles were long, thin, and floated on the water, while the other two were rounded into palms and spread to the wind like light sails,” notes our trusty narrator.

It’s an actual animal, alright, a rare and bizarre octopus that swims the open ocean: the argonaut. But those arms are no sails. (The myth persists in its name, though—the Argonauts being the Greek heroes who sailed around having sweet adventures.) The female argonaut uses them to form what is surely one of the most beautiful animal-made structures on Earth, an exceedingly delicate shell that she uses not to protect herself, but to house her young out there in the treacherous expanses of the sea. The males, though—things aren’t so great for them. Like, a sexual-dismemberment type of not so great.

Incredibly, females are up to 600 times the weight of the diminutive males, which grow to less than half an inch long and never build shells. According to marine biologist James Wood, though, there’s still a whole lot we don’t know about this mysterious creature, and its mating habits are no exception. What we do know is that when the male and female hook up, the male leaves something behind—other than sperm, of course. Specifically, it’s a specially adapted arm called a hectocotylus, “and there a little grooves on the arm that the sperm travels down and goes into the female’s oviduct,” Wood said. “So it’s not the penis. The penis is sort of inside the male, but that reproductive arm is used to transfer the sperm inside the female.”

The argonaut’s gorgeous shell posing on a beach all seductive-like.
When he jets away, the arm snaps off and stays with the female. It’s not clear if the male dies after copulation, but if he survives, the arm would probably grow back, because octopuses happen to be good regenerators. Some females have even been found with multiple hectocotyli in their shells from multiple males. Unsurprisingly, this odd sex caused quite some confusion for early observers. The famed 18th- and 19th-century naturalist Georges Cuvier determined the hectocotylus to be a species of parasitic worm, seeing things like a digestive tract that most certainly weren’t there (the name hectocotylus means “hollow thing”).

While almost all octopus species lay their eggs in crevices and caves and such, as an open-ocean swimmer, the argonaut has no such luxury. So as she grows, the female continually builds her shell—which is so thin it’s translucent—with those rounded arms, which secrete the mineral calcite. And when she’s finally ready to have kids, she’s got nice little crib for them. “So they can put them in this shell and they’re protected from the outside,” Wood said. “And the octopus can take care of them and brood them and clean them, make sure there’s no parasites, and oxygenate them.”

Argonauts can pop out of their shells whenever they like, unlike sea turtles. Also unlike sea turtles is pretty much everything else about the argonaut.
That shell serves another rather more cryptic purpose. I don’t want to tell them how to live their lives, but octopuses are supposed to be crawling around the sea floor, not floating around in the open ocean, and this presents the problem of buoyancy. Fish solve this with a gas-filled sac called a swim bladder, as do at least two other species of open-ocean octopuses, but the argonaut has a different solution.

By periodically coming to the surface and “gulping” air into its shell, the female can “seal off the captured gas using flanged arms and forcefully dive to a depth where the compressed gas buoyancy counteracts body weight,” wrote the researchers who discovered the function in 2010. And as her eggs grow and get heavier and heavier, she’ll be able to adjust for the added weight in this way. This is vitally important for a free-swimming octopus because constantly adjusting to maintain position sucks up a whole lot of energy. By becoming neutrally buoyant, the argonaut can kick back and relax.

The argonaut’s distant cousin, the nautilus.
The argonaut’s distant cephalopod cousin, the nautilus, accomplishes the same thing with its own shell, which is much thicker so as to function as armor and is permanently attached, whereas the argonaut can pop out of its shell whenever it likes. In fact, all cephalopods descended from shelled ancestors, but something happened over the course of their evolution that made them evolve away that shell—save for the nautilus, which is truly an ancient species. (The argonaut is also known somewhat confusingly as the paper nautilus, but again, they’re only distantly related.)

It may have been the case that big rude predators came along and were strong enough to break through those shells. “I use this analogy that we had knights and they would wear plate mail armor, so you had big heavy guys with big heavy armor and that was pinnacle of military combat,” said Wood. “And then we invented rifles and now a guy in heavy plate mail armor is a big slow target, because the ball is going to go through the plate mail, and it made it obsolete.”

Cephalopods were forced to adapt and develop new strategies or face extinction, and today we see them diversified into all manner of forms. While the argonaut’s shell is worthless as armor, the octopus still packs that iconic ink defense. Another species, the mimic octopus, seems to imitate other creatures you wouldn’t want to mess with like sea snakes and lionfish. And cuttlefish are absolute masters of camouflage, somehow blending into pretty much any environment even though they’re colorblind, which is…problematic if you’re a fan of reason. And almost all cephalopods have evolved an intelligence that is at times startling.

What’s interesting about the argonaut is that its ancestors long ago evolved away the shell, then later on evolved an entirely new way of constructing it and an entirely new use for it as a reproductive aid. Still, though, it arrived at the same solution to the buoyancy problem that the early cephalopods solved with their own shells, which just goes to show what an endlessly creative force evolution is.

Perhaps I’m making the argonaut seem like a helpless floating piece of meat, though. Like any other cephalopod, this is a voracious carnivore, targeting all kinds of crustaceans and sea slugs and other free-swimming prey. Once it’s got a hold on the quarry, the argonaut gnaws into the victim with its beak and injects a toxin (the chemicals at work here differ between cephalopods, and it’s not yet known what’s in the argonauts, according to Wood). Then, using a conveyor belt of tiny teeth known as a radula, it’ll scrape away the meat—or in the case of a hard-shelled prey, scoop out the contents through the hole created by the beak.

Read more at Wired Science

Jan 15, 2015

Sea Turtles Magnetically Drawn to Fave Beaches

Adult female sea turtles are literally magnetically drawn to the comforting beaches where they were hatched, finds new research.

What’s more, scientists suspect that tiny magnetic particles in sea turtle brains enable them to detect unique magnetic signatures given off by beaches, such that they can return to them after ultra long journeys.

The findings, published in the latest issue of the journal Current Biology, help solve a long-standing mystery.

“Sea turtles migrate across thousands of miles of ocean before returning to nest on the same stretch of coastline where they hatched, but how they do this has mystified scientists for more than fifty years,” co-author J. Roger Brothers of the University of North Carolina, Chapel Hill, said in a press release.

“Our results,” continued Brothers, “provide evidence that turtles imprint on the unique magnetic field of their natal beach as hatchlings and then use this information to return as adults.”

Prior research determined that sea turtles use the Earth’s magnetic field as a guide while out at sea. It wasn’t clear, though, whether adult female turtles also used this technique to identify and return to the nesting sites chosen by their mothers.

What’s good for mother turtle is good for her adult offspring too, since the latter don’t bother trying to hunt down better beaches. Mom’s choice is the only one.

“We reasoned that if turtles use the magnetic field to find their natal beaches, then naturally occurring changes in the Earth’s field might influence where turtles nest,” Brothers said.

To test this out, the researchers analyzed a 19-year database of loggerhead nesting sites along the eastern coast of Florida, which has the largest sea turtle rookery in North America. The scientists found a strong association between the spatial distribution of turtle nests and subtle shifts in the Earth’s magnetic field.

For example, in some cases the Earth’s field shifted so that the magnetic signatures of adjacent locations along the beach moved closer together. When that happened, nesting turtles packed themselves along a shorter stretch of coastline. In places where magnetic signatures diverged, sea turtles spread out and laid their eggs in nests that were fewer and farther between.

Read more at Discovery News

Ancient Scorpion Had Feet, May Have Walked Out of Ocean

A new scorpion species found fossilized in the rocks of a backyard could turn the scientific understanding of these stinging creatures on its head.

The fossils suggest that ancient scorpions crawled out of the seas and onto land earlier than thought, according to the researchers who analyzed them. In fact, some of the oldest scorpions had the equipment needed to walk out of their watery habitats and onto land, the researchers said. The fossils date back some 430 million to 433 million years, which makes them only slightly younger than the oldest known scorpions, which lived between 433 million and 438 million years ago.

The new species "is really important, because the combination of its features don't appear in any other known scorpion," said study leader Janet Waddington, an assistant curator of paleontology at the Royal Ontario Museum in Toronto.

The new species fell into Waddington's hands almost by happenstance. Museum curators frequently get calls about fossils, most of which are run-of-the-mill, she told Live Science. But a woman who called about an "insect" in her backyard stone wall had something very exciting on her hands.

"When she showed me this fossil, I just about fell on the floor, it was so amazing," Waddington said.

The fossil was no insect, but rather a scorpion — and a new species at that. Over the years, more specimens trickled in, mostly from patio stones and rock quarries, and one from a mislabeled fossil at a national park on Canada's Bruce Peninsula. Now, Waddington and her team have 11 examples of the new species, ranging in length from 1.1 inches (29 millimeters) to 6.5 inches (165 millimeters).

What made the animal, dubbed Eramoscorpius brucensis, so fascinating was its legs.

Previously, the earliest scorpion fossils found came from rocks that were originally deposited in the water, leading paleontologists to believe that the animals evolved on the seafloor, like crabs, and only later became landlubbers. Ancient scorpions had legs like crabs, with a tarsus, or foot segment, that was longer than the segment preceding it. This arrangement, Waddington said, would have meant the creatures walked on their "tippy-toes," such as crabs do today.

But E. brucensis was different. This species had a tarsus segment that was shorter than the segment before it, which would have made it possible for the animal to set its tarsus flat against the ground. In other words, this scorpion had feet.

"They could have walked on their feet, which is really important because it meant that they could have supported their own weight," Waddington said. Without the need for water to buoy them up, the animals could have walked on land.

The fossils also show that the scorpions' legs were solidly attached at the body, without the exaggerated "hinge" seen in scorpions that would have needed water to stay upright. What's weird, Waddington said, is that all the other features of these scorpions seem aquatic. They are found in marine rocks, and their digestive systems appear to require water (in today's land scorpions, digestion begins outside of their bodies, a process that requires adaptations these ancient scorpions lack).

Waddington said she and her team suspect that the fossils they've collected are not the bodies of dead scorpions at all. Instead, they may be molts, exoskeletons left behind as the scorpions grow. Scorpions are incredibly vulnerable during molting, Waddington said, and in deep water, ancient squidlike animals would have loved a helpless scorpion snack. The scorpions that could haul themselves out of the water onto the shore to escape predators would have had a survival advantage. The rocks that house the scorpion fossils often feature ripples that would have been created when wind blew thin films of water over land, suggesting a shoreline lagoon habitat.

Read more at Discovery News

16th-Century 'Lenox Globe' Gets Digital Makeover

In a dark room at the New York Public Library, a cartographer, a curator of rare books and a handful of scientists crowded around a camera ringed by colored lights. All eyes were trained on a small, copper sphere about the size of a grapefruit: the Lenox Globe, the oldest surviving globe to depict the New World.

By imaging the globe from top to bottom and conducting a 3D scan of it, the researchers plan to provide a precise digital record of the object that will last for generations, giving scholars and members of the public a glimpse at what people knew about world geography in the early 1500s.

Chet Van Duzer, a cartographer currently based at the Library of Congress in Washington, D.C., is leading the effort to image the ancient orb.

"It's the first globe with a record of the New World, it's pretty widely agreed ," Van Duzer told Live Science. The orb only depicts the continent of South America, though the existence of North America was known at least in some circles, Van Duzer said.

A masterpiece of workmanship, the Lenox Globe measures 4.4 inches across (11.2 centimeters), and the hollow copper sphere is engraved with almost microscopic detail. The globe's maker is unknown and its age is disputed, but based on the geography it depicts, some historians say the object was likely made between 1503 and 1507.

A rainbow of imaging

To capture the globe in digital form, the team used a method that involves imaging the object in a variety of different colors, or wavelengths. The technique, known as multispectral imaging, captures the object's color most faithfully, and provides a complete record of it, Van Duzer said.

The researchers took 18 pictures around the globe's equator, 39 images at various latitudes and one of the pole; then, they repeated the process for the Southern Hemisphere. Different colored lights were used to capture the images at different wavelengths, including ultraviolet, which is powerful enough to damage your eyes if you don't shield them, the researchers cautioned.

The imaging was done in conjunction with the Lazarus Project, an organization that provides access to advanced imaging technology to historical researchers.

"We provide multispectral imaging and 3D imaging for cultural heritage of objects, financed through charity," said Gregory Hayworth, director of the Lazarus Project and an English professor at the University of Mississippi, in Oxford.

But imaging a curved surface isn't easy. "You need to have a flat field, otherwise the play of light will alter the color, and it will alter the geometry," Hayworth told Live Science. Because the globe is made of metal, it disperses light — "it's like taking a photograph of a mirror," so capturing the globe's true colors is difficult, he said.

Although the globe looks spherical, it's not perfect, which can cause distortion in the 3D digital replica. So, after taking the high-resolution color images, the researchers made 3D scans of the globe. By wrapping the 2D multispectral images around the 3D scan, they can get a much more accurate reconstruction of the globe, Hayworth said.

History of the globe

Not much was known about the Lenox Globe until 1850, when an architect named Richard Morris Hunt purchased the globe at a flea market in Paris, according to Michael Inman, curator of rare books at the New York Public Library. In the 1860s, Henry Stevens, an agent for the New York City rare book collector James Lenox, was visiting Hunt when he noticed Hunt's children rolling a small copper sphere around on the floor. Stevens asked Hunt if he could borrow the globe and examine it.

Upon finding out it was the oldest known terrestrial globe to depict the Americas, Hunt donated the globe to the Lenox Library, which is now part of the New York Public Library. It's been there ever since.

The Library declined to comment on the globe's value.

Read more at Discovery News

1882 Winchester Rifle Found Leaning on Tree in Park

Officials at Nevada’s Great Basin National Park are working to solve the mystery of an 132-year-old Winchester rifle found leaning against a tree in the park.

Great Basin archaeologists found the rifle in November, which appeared to have been long exposed to sun, wind, snow and rain.

“The cracked wood stock, weathered to grey, and the brown rusted barrel blended into the colors of the old juniper tree in a remote rocky outcrop, keeping the rifle hidden for many years,” the park said.

The finding left the park employees wondering. Who left the rifle? When and why it was leaned on the tree? And, why was it never retrieved?

“Right now there are more questions than answers,” Nichole Andler, chief of Interpretation at Great Basin, told Discovery News.

“What we do know is the ‘Model 1873′ distinctively engraved on the mechanism identify the rifle as the Winchester Model 1873 repeating rifle,” she added.

She noted that the serial number on the lower tang corresponds with manufacture and shipping records dating to 1882.

“Currently, the detailed history of this rifle is unknown. Winchester records do not indicate who purchased the rifle from the warehouse or where it was shipped,” Andler said.

Referred to as “the gun that won the West,” Winchester manufactured 720,610 of the rifles between 1873 and 1916, when production ended. In 1882 alone, more than 25,000 were made.

Indeed, in 1882 it was sold as “everyman’s rifle” for about $25.

Read more at Discovery News

Jan 14, 2015

How Greenland Got Its Glaciers

Greenland is famous for its massive glaciers, but the region was relatively free of ice until about 2.7 million years ago, according to a new study. Before then, the Northern Hemisphere had been mostly ice-free for more than 500 million years, the researchers said.

The Greenland ice sheet began building after plate tectonics and the Earth's shifting tilt reshaped the region, the researchers found. The team narrowed the cause down to three factors: plate tectonics that lifted the region, creating soaring snow-capped mountain peaks; a northward drift from plate tectonics; and a shift in the Earth's axis that caused Greenland to move farther north, away from the sun's warmth.

"Our work was motivated by the question of why extensive glaciations of Greenland started only during the past few million years," the researchers wrote in the study.

About 60 million years ago, a plume from the Earth's mantle, several layers below the planet's upper crust, thinned out part of Greenland's lithosphere above it.

In some parts of Greenland, the lithosphere can be about 124 miles to 186 miles (200 to 300 kilometers) thick. But because of the plume, the lithosphere in East Greenland is often thinner than 62 miles (100 km), making it easy for rising hot rocks in the mantle to cause uplift.

About 5 million years ago, hot rocks underneath Iceland rose from Earth's mantle, and flowed northward toward East Greenland. With an already-thin lithosphere, this underground activity easily bolstered Iceland's mountains, causing them to reach more than 1.9 miles (3 km) above sea level.

In West Greenland, where the lithosphere is thicker, the mountains reach less than 1.2 miles (2 km) above sea level, the researchers said.

When the scientists applied the underground activity from Iceland to a computer model, they saw how it acted over time.

"These hot rocks flow northward beneath the lithosphere, that is, towards eastern Greenland," the study's lead researcher, Bernhard Steinberger, of the German Research Centre for Geosciences GFZ, said in a statement. "Because the upwelling beneath Iceland — the Iceland plume — sometimes gets stronger and sometimes weaker, uplift and subsidence can be explained."

Moreover, the researchers found clues in the eastern part of the country, where glaciation first began. Dating showed that rock samples from the tops of mountains in East Greenland were uplifted within the past 10 million years, when the hot rocks would have been pushing up the mountains.

Moving northward

But major glaciation in Greenland didn't start because of the mountain's uplift. Other factors were at play, the researchers found. Before 60 million years ago, Greenland was located at lower, and warmer, latitudes, the scientists said.

Plate tectonic reconstruction shows that over the past 60 million years, Greenland has moved about 497 miles (800 km) to the northwest over the mantle. This is equivalent to Greenland shifting 6 degrees northward on the globe, the researchers said.

The northerly move was magnified by "true polar wander," when the Earth's outermost layers naturally tilt and change location.

"Our computations show that the Earth axis shifted about 12 degrees towards Greenland during the last 60 million years" Steinberger said.

Between the tectonic plate movement and true polar wander, Greenland moved about 18 degrees to the north over the past 60 million years, the researchers found. Greenland's colder location, combined with its new, high mountains in the east, created opportune conditions for glacier formation, the researchers said.

Read more at Discovery News

People Erode Soil 100 Times Faster Than Nature

Cutting down or burning native forests and starting intensive agriculture -- that is, industrial-scale farming, designed to produce high yields of crops and/or animals -- can accelerate erosion dramatically, reports a newly-published study from researchers at the University of Vermont.

It causes so much damage, in fact, that in a few decades as much soil is lost as would naturally occur over thousands of years.

The researchers, who studied 10 large river basins in the southeastern United States, found that the damage started to occur hundreds of years ago, when large numbers of settlers arrived from Europe, and accelerated as agriculture developed. Before the 1700s, hillsides along the rivers eroded at a rate of about an inch each 2,500 years. But by the time erosion peaked in the late 1800s and early 1900s thanks to logging and tobacco and cotton cultivation, the hills were losing an inch every 25 years.

“Our study shows exactly how huge an effect European colonization and agriculture had on the landscape of North America,” says one of the researchers, Dylan Rood, “humans scraped off the soil more than 100 times faster than other natural processes.”

The study was published in the journal Geology.

The scientists came up with their findings by collecting sediment samples and then using an accelerator mass spectrometer at the Lawrence Livermore National Laboratory to help them measure the quantity of a rare isotope, beryllium-10, in quartz in the sediment. The isotope, formed by cosmic rays, builds up in the top of soil. As the erosion rate increases, the soil accumulates less beryllium-10.

Read more at Discovery News

Mystery of 'Human Finger' Found on Beach Solved

Last week a man walking along a beach in northern Australia found what appeared to be a severed human finger and wondered if he may have stumbled across a crime scene.

According to an ABC News article, “The man was walking his dog along the beach at Lee Point, north of Darwin, when the animal took an interest in the object. The man feared he had discovered the remains of a murder victim and quickly called Northern Territory Police.”

Grisly, Grizzly, or Just Gross?

While some unfortunate beachcombers do sometimes come across washed up body parts, it’s very rare. The phenomenon of people finding apparently gruesome human body parts that turn out to be something else is not as unusual as it may seem. Decomposing bear bones and paws, for example, have sometimes been mistaken for human hands and fingers because the ursine skeletal structure in the paws is similar to that of humans.

It's clear why the police took the report seriously; obviously anything that might be human remains could be important homicide evidence until proven not to be.

In his book "Practical Homicide Investigation: Tactics, Procedures, and Forensic Techniques," veteran homicide detective Vernon Geberth notes that "Practically speaking, law enforcement personnel should consider all pieces of skeleton human until experts determine otherwise. For example, parts of bear paws are misidentified more often as human than any other animal. In addition, many animal skeletons lacking the telltale skull have been thought to be those of a small child."

The confusion is not merely hypothetical, and it’s not uncommon. In 2004 a West Virginia man discovered what looked like a human hand at a car wash; police at first believed it was a child’s hand but the state forensics lab determined it was a decomposed bear paw. The grisly discovery of what seemed to be a child’s foot found in Queens, N.Y., in 2011 also turned out, thankfully, to be a bear paw.

Solving the Mystery

In this case the weird fingerlike thing on the Darwin beach wasn’t from a bear or other mammal; a police pathologist determined that while it was organic it was not in fact a human digit, lacking skin or bones. It was initially thought to be a type of coral called Alcyonium digitatum, otherwise known as “dead man’s fingers.” A search of images for the coral did reveal a resemblance, and some called it case closed.

Read more at Discovery News

Fantastically Wrong: Why So Many People Think They’ve Seen Ghost Dogs With Glowing Eyes

This one’s eyes are closed so you can’t tell that they’re glowing. Promise.
At the height of World War II, a four-year-old British girl was sent to bed but could not sleep. Sitting on edge of her bed, fiddling with its ornamental knobs and staring out the window, the girl heard a scratching noise. Then, out of the corner of her eye, a massive black dog appeared and trotted in front of her, turning its head to stare at her as it passed between the bed and the window.

“It had very large, very red eyes, which glowed from inside as if lit up,” she later recounted, “and as it looked at me I was quite terrified, and very much aware of the creature’s breath, which was warm and strong as a gust of wind.” But before it had reached the door, it vanished.

It was a hound that goes by many names: black shuck, the hellhound, black jack, gallytrot. Depending on the observer, it can also be white or yellow; it rarely speaks but sometimes laughs; every once in a while it’s missing its head completely; and a few have been known to shapeshift. And it’s not just England that the hellhound stalks—similar tales can be found all over the world. (I’ll be referring to it as the hellhound from here on out, because that best encompasses all of the versions out there.) But why is this myth so widespread? And how can we explain why so many people have claimed to have seen the hound?

This tale necessarily begins with the wolf. Humankind has had a long, complicated relationship with the beast, largely because before we’d fully ascended to the top of the food chain, wolves were a serious threat. But with time they warmed up to us. They’d hang around our fires, waiting for our scraps, while the bolder ones slowly edged closer. In time, we domesticated the wolf into the dog. Their wild brethren, though, remained hostile, and to this day have been known to attack humans (our attacks on them, it should be noted, have been far more frequent and devastating).

Don’t get much more majestic than the wolf. Except maybe a wolf with like, a top hat or something.
Fast-forward several thousand years to ancient Greece and the dog is firmly planted in mythology with Cerberus, the three-headed hound that guards the underworld. But this is far from the only association of dogs with the underworld, according to Bibek Debroy in his book Sarama and Her Children: The Dog in Indian Myth. “For instance,” he writes, “in ancient Persia, dogs were the preferred means of disposing dead bodies.” Elsewhere around the world, stray dogs resorted to scavenging—at times on humans—earning them an association with death.

However, Debroy notes, “this association with the afterworld or dead souls did not prevent dogs from being elevated to divinity.” There’s the ancient Egyptian Wepwawet, a dog-like god that opened roads to the underworld. The Aztecs also deified the dog as Xolotl, who carried the sun through the underworld. So just as our relationship with wolves was complicated, so too is our relationship with dogs the world over. We’ve feared them as creatures of the underworld, yet rely on them for companionship.

Alcohol and Other Factors That Just Might Have Led to the Hellhound

So that’s the cultural background, but what about the cause of the hellhound phenomenon? It’s worth relating another experience, this time from Simon Sherwood of England’s University of Northampton. When he was around three to five years old, he awoke to the patter of feet. “I looked up thinking it was my dog, but to my terror I saw a massive black animal probably with horns, but perhaps ears, galloping along the landing towards my bedroom. I tried to scream but I found it impossible. The creature’s eyes were bright yellow and as big as saucers. The animal got to my bedroom door and then vanished as quick as it has appeared. I then managed to scream and my mum came in to calm me down.”

There’s a very important clue here, which Sherwood himself quite rightly recognizes (he goes on to uncritically report other more paranormal and impossible potential causes of the phenomenon, but whatever). Not being able to speak or move while still seemingly conscious is a classic symptom of sleep paralysis, which happens when the brain and the body are out of sync during sleep.

Tales of ghost dogs have been floating around England for hundreds of years, and I’m willing to bet they’ll be around for hundreds more.
During REM sleep, your muscles are so relaxed that they’re essentially worthless (which, by the way, may be an evolutionary trick to keep you from acting out your dreams and injuring yourself). Should you wake up, though, and your muscles don’t immediately kick back into gear, you can feel paralyzed and probably quite a bit panicked. But soon enough it’s all over. This would explain why Sherwood was unable to scream at first, then eventually recovered his voice.

Some people like Sherwood even hallucinate and see a giant black dog, for example. But why would reports of the hellhound be largely consistent? Well, folklore is a powerful thing, even for a child, especially when it’s terrifying. Tales of ghost dogs have been floating around England for hundreds of years, and I’m willing to bet they’ll be around for hundreds more. Well, at least until we come up with a good treatment for sleep paralysis.

There are other stories, though, of wide-awake folks seeing evil dogs out in the open. An account from 1908 of an Englishman walking home from an inn: “I suddenly saw an animal that seemed to be like a large, black dog appear quite suddenly out of the hedge and run across the road quite close in front of me; I thought it was the dog belonging to the curate. I was just going to call it to send it home, when it suddenly changed its shape, and turned into a black donkey standing on its hind legs. This creature had two glowing eyes, which appeared to me to be almost as big as saucers. I looked at it in astonishment for a minute or so, when it suddenly vanished.”

Fun fact: Hellhounds love car rides, just like regular dogs. Except they fall out easy, because they’re ghosts and just kinda float through things.
Whether or not the man had tied on a few at the inn is lost to history, but I suspect as much. Experiences like this can be explained by … the existence of big dogs and the existence of alcohol and drugs. And those glowing eyes? They have a perfectly rational explanation as well.

Some creatures, including cats, raccoons, and dogs, have a layer of reflective tissue in their eyes known as the tapetum lucidum. This acts like a mirror to bounce light at the retinal cells for a second pass, greatly enhancing night vision. It’s responsible for eye-shine, that glow you get if you snap a flash at your dog or cat. And it’s not hard to imagine that it’s this eye-shine that gave rise to the myth of a hound with burning eyes.

Read more at Wired Science

Jan 13, 2015

Tiny Fish Skull May Be Ancestor of Jawed Vertebrates

The remains of a 415-million-year-old fish skull from Siberia — though miniscule in size — offer hints about the origins of all jawed vertebrates, ranging from reptiles to humans, a new study finds.

Researchers originally uncovered the roughly 0.8-inch-long (2 centimeters) skull in the 1970s, and classified the specimen as a bony fish. There are two main types of living jawed vertebrates: those made of bone and those made of cartilage. Now, a new, more in-depth examination of the ancient fish's brain case shows that the fossil has characteristics of both bony fish, such as salmon and trout, and fish made of cartilage, including sharks and manta rays.

The Siberian fossil also suggests that sharks — which are made of cartilage and long thought to be more primitive than bony-jawed vertebrates — are more evolved than had been previously thought, the researchers said.

"It's a very interesting fossil, and it's very small," said Sam Giles, the study's lead researcher and a paleobiology doctoral candidate at Oxford University in the United Kingdom. "It's surprising that something so tiny could have so much information in it."

The researchers named the new genus Janusiscus schultzei, for "Janus," the Roman god of doorways and transitions, who is often depicted with two faces, and the Latin "piscis" for fish. The species is also named for Hans-Peter Schultze, of the University of Kansas, who first described the fossil in 1977.

Giles and her colleagues used a specialized computed tomography (CT) scanner to look at the skull, which was still embedded in rock. They imaged the fossil hundreds of times from different angles, allowing them to create a 3D model.

The incredibly detailed scans show that the fish has sensory line canals on its skull. Bony fish use these canals, located on the outside of the body, to sense changes in pressure around them and avoid predators.

But the skull also has features characteristics of fish made of cartilage. The scans showed that there are blood vessels at the bottom of the ancient fish's brain case, located inside the skull, above and between the jaws,that supply the brain with oxygen. The blood vessels are something that "is a lot more like you would see in a cartilaginous fish," Giles told Live Science.

Although bony and cartilaginous fish had a common ancestor, they split apart around 420 million years ago, Giles said. The Siberian fossil is likely one of the common ancestors of the two groups, and may provide clues as to what the animals' earliest common ancestor looked like.

"There are over 60,000 species of living jawed vertebrates, and they encompass pretty much everything you can think of [with a backbone] that lives on land or in the sea," Giles said. "But we don't really know what they looked like when they split."

Moreover, researchers have long believed that the common ancestor of bony and cartilaginous fish had more cartilage than bone, Giles said. This would mean that vertebrates made of cartilage, such as sharks, would have evolved less over the ages than did bony creatures.

"But what this animal tells us that actually the last common ancestor of the two groups had lots of bone," Giles said. "So rather than sharks being primitive, sharks are actually very highly evolved in their own way, and just as highly evolved as we are."

The new findings are "truly remarkable," said John Long, a professor of paleontology at Flinders University in Adelaide, Australia, who was not involved with the study.

"I think it is a highly significant discovery, as the origin and diversification of modern bony-jawed fishes is still shrouded in mystery," Long told Live Science in an email. "But Janiusiscus takes us a big step closer to really understanding this major evolutionary transition, from primitive jawed fishes to the beginning of the modern jawed fish fauna."

Read more at Discovery News

First Conversations 2 Mln Yrs Ago Likely About Tools

The first verbal conversations likely occurred between 2.5 and 1.8 million years ago and were about tool-making, a new study suggests.

The study, published in the journal Nature Communications, presents compelling evidence that stone tool-making helped to drive the evolution of language and teaching among prehistoric human ancestors in the African savanna. A possible first sentence might have been, "Tool bad."

"We suggest that the use of tools drove the evolution of language, and it seems likely that 'words' for things other than current emotional states would have been very useful for learning to knap," lead author Thomas Morgan told Discovery News.

"The use of sounds or gestures for non-emotional concepts such as 'yes,' 'no,' 'here,' 'there,' 'good' and 'bad' would likely have been really useful," added Morgan, who is a postdoctoral researcher in psychology at the University of California at Berkeley.

Morgan, University of Liverpool archaeologist Natalie Uomini and their team conducted a series of experiments in teaching contemporary humans the art of "Oldowan stone knapping." Oldowan refers to the oldest known stone cutting tools, which were likely made by Homo habilis (aka "The Handy Man") and possibly also Homo rudolfensis, Australopithecus garhi and Paranthropus boisei.

The earliest known Oldowan tools date to 2.5 million years ago. They consist of butchering "flakes" created by hammering a hard rock against certain volcanic or glassy rocks, like basalt or flint. The tools remained largely unchanged until 1.8 million years ago, when more sophisticated Acheulean hand-axes and cleavers marked the next generation of stone tool tech.

In testing five different ways to convey Oldowan stone-knapping skills to more than 180 college students, the researchers found that the demonstration using spoken communication, versus imitation, non-verbal presentation or gestures, yielded the highest volume and quality of flakes in the shortest amount of time and with the least waste.

He suspects that other tasks, such as hunting and gathering, also could have been involved in the development of language and teaching skills, but probably not to the same degree as tool making.

Since language has likely been around for at least 2 million years, there is little doubt that other human-like species, such as Neanderthals, did a lot of talking.

"Language was certainly already present before the Neanderthals and our ancestors split," Uomini said. "The Neanderthals had some of the most complex stone tools ever made, which are also the most difficult for modern day knappers to replicate. That's why we think that their communication and teaching system must have been sophisticated enough to transmit the subtle and long 'recipes' for making their tools."

Erella Hovers of the Hebrew University of Jerusalem's Institute of Archaeology said that the new study offers "some intriguing ideas," but she is not sure that the lack of stone tool tech advancement just after 2.5 million years ago "can be attributed exclusively to low-fidelity teaching modes."

Dietrich Stout, an assistant professor of anthropology at Emory University, has conducted studies on the cognitive mechanisms underlying tool making. He recently trained subjects to make stone tools over a 2-year period and measured changes in their brain structure associated with learning. The results showed that brain systems associated with language were affected, supporting the proposed link between tool manufacture and language.

Read more at Discovery News

Animal DNA on the Go Seen for First Time

A type of DNA for the first time has been observed moving from one cell to another in animals.

Genetic material called mitochondria convert energy from food into a form that can be used by cells. In the experiment, a tumor cell without mitochondrial DNA formed tumors after pulling in DNA from normal cells.

“Our findings overturn the dogma that genes of higher organisms are usually constrained within cells except during reproduction," Mike Berridge, a professor from the Malaghan Institute of Medical Research in New Zealand, said in a statement. "It may be that mitochondrial gene transfer between different cells is actually quite a common biological occurrence.”

Berridge along with Jiri Neuzil from Griffith University in Queensland, Australia, led a team that examined breast cancer tumors in mice. Mitochondrial DNA was removed from cells, which then pulled replacement DNA from surrounding, normal mouse tissue.

The effect has been observed in the lab before, the researchers said, but not in an animal tumor.

The researchers initially thought the cells had adapted to grow without the mitochondrial DNA that had been removed. But after testing, the scientists discovered the cells did have mitochondrial DNA pulled from non-tumor cells.

The researches say the findings may help in understanding more about 200 diseases besides cancer that involve defective mitochondrial DNA. "It could also usher in a new field where synthetic mitochondrial DNA is custom-designed to replace defective genes," the researchers wrote.

If mitochondrial DNA sounds familiar, that may be because it's used in studying human ancestry. The genetic material is passed down only by one's mother, and has been instrumental in tracing a common human ancestor back to Africa 60-70,000 years ago.

The results were published in the journal Cell Metabolism.

From Discovery News

Monster Black Hole Belches Record Flare

The giant black hole at the center of the Milky Way galaxy recently spit out the largest X-ray flare ever seen in that region, astronomers say.

The enormous eruption from the Milky Way's core was detected on Sept. 14, 2013, very close to the supermassive black hole known as Sagittarius A*. Pronounced "Sagittarius A star" and abbreviated as Sgr A*, the Milky Way's monster black hole has a mass that is about 4.5 million times that of the sun. Scientists unveiled the discovery of the record-breaking flare this month at the 225th meeting of the American Astronomical Society.

The so-called "megaflare" was spotted by NASA's Chandra X-ray Observatory, which can peer through dust and starlight to the center of the Milky Way. The event was 400 times brighter than the normal level of radiation from this region and nearly three times brighter than the previous record-holding flare, recorded in 2012. A second X-ray flare, with a flash 200 times brighter than normal levels, was then seen on Oct. 22, 2014.

Daryl Haggard, of Amherst College in Massachusetts, presented the findings at a news conference here at the AAS meeting on Jan. 5. Haggard and her colleagues have two possible explanations for what might have caused the flare. First, the black hole may be behaving like our own sun, which also emits bright X-ray flares. In the sun, these flares occur when magnetic-field lines become very tightly packed together or twisted, and the researchers said it's possible something similar took place near the black hole.

It's also plausible that the flare was the product of Sgr A* having a snack. An asteroid or other object may have come too close to the black hole, ripping it apart. The debris would have accelerated rapidly and potentially radiated a bright burst of X-rays.

"If an asteroid was torn apart, it would go around the black hole for a couple of hours — like water circling an open drain — before falling in," Fred Baganoff, of the Massachusetts Institute of Technology and a member of the research team, said in a statement. "That's just how long we saw the brightest X-ray flare last, so that is an intriguing clue for us to consider."

Researchers saw the flare by chance while watching Sgr A* in anticipation of a different event: A gas cloud called G2 was set to make a close pass by Sgr A*, and some scientists hypothesized that material from G2 would fall into the black hole, generating a bright display of X-rays, NASA officials said in a statement. But no X-ray signal was detected as G2 made its closest approach to Sgr A*. The new flares do not appear to be part of the missing light show, according to Haggard.

"We do not think flares are connected to the G2 object," Haggard said. "And the reason for that is that the time scales don't quite match. The time scale for these flares is fairly rapid — thousands of seconds," or an hour or two, she said.

Read more at Discovery News

Jan 12, 2015

They see flow signals: Researchers identify nature of 'sixth sense' in fish

A team of scientists has identified how a "sixth sense" in fish allows them to detect flows of water, which helps resolve a long-standing mystery about how these aquatic creatures respond to their environment. Their findings, which appear in the journal Physical Review Letters, illustrate how sensory systems evolve in accordance with physical principles while also offering a framework for understanding how sensory networks are structured.

"We identified a unique layout of flow sensors on the surface of fish that is nearly universal across species, and our research asks why this is so," explains Leif Ristroph, an assistant professor at New York University's Courant Institute of Mathematical Sciences and one of the study's authors. "The network of these sensors is like a 'hydrodynamic antenna' that allows them to retrieve signals about the flow of water and use this information in different behaviors."

The study's other authors were James Liao, an assistant professor at the University of Florida's Whitney Laboratory for Marine Bioscience, and Jun Zhang, a professor of physics and mathematics at NYU and NYU Shanghai.

It is well known that fish respond to changes in their fluid environment. These include avoiding obstacles, reducing swimming effort by slaloming between vortices, or whirlpools, and tracking changes in water flow left by prey -- even without the aid of vision.

To explore how fish exploit flow information, the research team focused on a fish's "lateral line" -- a system of sensory organs known to detect both movement and vibration in the water that surrounds them -- with particular consideration to the line's sensory-laden canals that open to the environment through a series of pores. They specifically focused on the placement of these canals along the body, noting that their location can help explain how a fish's sixth sense functions. For instance, the concentration of these canals at the heads of blind cave fish seems well-suited for detecting obstacles.

To test their theory, the researchers created a plastic model of a rainbow trout that replicated the location of the fish's canals and included illuminated markers used to detect the speed of surrounding water.

In their experiments, the model fish was put through a series of tests the replicated real- life aquatic conditions -- changes in water flow that altered water pressure or mimicked the presence of "prey" -- and examined where the canals were located in relation to strongest changes in water pressure.

Their results showed that, as predicted, the canal system is concentrated at locations on the body wherever strong variations in pressure occur. Just as the shape of a TV or radio antenna is designed to detect electromagnetic signals, the fish's canal system is like an antenna laid out on the body surface and configured to be sensitive to pressure changes. The team's use of finely detailed models -- developed with the help of a taxidermist who made custom molds from real trout -- made it possible to record this data for the first time.

Read more at Science Daily

Two-faced fish clue that our ancestors 'weren't shark-like'

An investigation of a 415 million year-old fish skull strongly suggests that the last common ancestor of all jawed vertebrates, including humans, was not very shark-like. It adds further weight to the growing idea that sharks are not 'primitive'.

The fossil skull's external features meant it had always been thought to belong to the bony fishes (osteichthyans), a group which includes familiar fishes such as cod and tuna as well as all land-dwelling creatures with backbones. But when scientists from Oxford University and Imperial College London used X-ray CT scanning to look inside the skull they found the structure surrounding the brain was reminiscent of cartilaginous fishes (chondrichthyans) such as sharks and rays. The fish fossil's 'two faces' led to it being named Janusiscus after the double-faced Roman god Janus.

A report of the research is published in the journal Nature.

'This 415 million year-old fossil gives us an intriguing glimpse of the 'Age of Fishes', when modern groups of vertebrates were really beginning to take off in an evolutionary sense,' said Dr Matt Friedman of Oxford University's Department of Earth Sciences, an author of the report. 'It tells us that the ancestral jawed vertebrate probably doesn't fit into our existing categories.'

Chondrichthyans have often been viewed as primitive, and treated as proxies for what the 'ancestral' jawed vertebrate would have looked like. A key component of this view is the lack of a bony skeleton in cartilaginous fishes.

'The results from our analysis help to turn this view on its head: the earliest jawed vertebrates would have looked somewhat more like bony fishes, at least externally, with large dermal plates covering their skulls,' said Sam Giles of Oxford University's Department of Earth Sciences, first author of the report. 'In fact, they would have had a mix of what are now viewed as cartilaginous- and bony fish-like features, supporting the idea that both groups became independently specialised later in their separate evolutionary histories.'

Dr Friedman said: 'This mix of features, some reminiscent of bony fishes and others cartilaginous fishes, suggests that humans may have just as many features that you might call 'primitive' as sharks.'

The fossil skull was originally found near the Sida River in Siberia in 1972 and is currently held in the Institute of Geology at the Tallinn University of Technology, Estonia. Study author Martin Brazeau of Imperial College London spotted the specimen in an online catalogue and the team decided it would be worth studying in greater detail using modern investigative techniques.

The team then used X-ray CT (computed tomography) to 'virtually' cut through the fossil. Different materials attenuate X-rays to different amounts -- just as in a hospital X-ray, bones show up brighter than muscles and skin. This same principle can be applied to fossils, as fossilised bone and rock attenuate X-rays to different degrees. This technique was used to build a 3D virtual model of the fossil, enabling its internal and external features to be examined in great detail. Traces left by networks of blood vessels and nerves, often less than 1/100th of a centimetre in diameter, could then be compared to structure in a variety of jawed vertebrate groups, including sharks and bony fishes.

Read more at Science Daily

Motorboat-Sized Predator Swam in Jurassic Scotland

A motorboat-sized beast that was at the top of its food chain 170 million years ago is Scotland's first known native marine reptile.

The formidable ocean predator, described in the latest issue of the Scottish Journal of Geology, might have munched on dinosaurs and sharks, since both also lived at or around what is now the Isle of Skye. The predator was an ichthyosaur, meaning an extinct marine reptile that had a pointy head, four flippers and a vertical tail. Together, these features made such animals look like sinister dolphins.

A group of paleontologists working in Scotland studied the remains of the newly discovered ichthyosaur, named Dearcmhara shawcrossi. Dearcmhara --[/i ]pronounced jark vara -- is Scottish Gaelic for "marine lizard." The species is one of just a handful ever to have been given a Gaelic name.

"Believe it or not, this is the first distinctly Scottish marine reptile species that has ever been described, and our paper is the first paper on ichthyosaurs from Scotland," project leader Steve Brusatte of the University of Edinburgh's School of GeoSciences told Discovery News.

Remains of the animal were found at the Isle of Skye's Bearreraig Bay, where amateur collector Brian Shawcross found them. Instead of keeping or selling them, which often happens, Shawcross donated the specimens to the Hunterian Museum in Glasgow. This allowed researchers to study them, determine their significance and piece together what this animal looked like in the flesh.

"It would have been roughly 14 feet long or so, and probably would have fed on fish and marine invertebrates," Brusatte said.

Much of Skye was under water 170 million years ago. Skye was joined to the rest of the U.K. then, and was part of a large island positioned between land masses that gradually drifted apart and became Europe and North America.

Sharks in the region during the marine reptile's lifetime were generally smaller and more primitive than today's sharks, so it's possible that Dearcmhara ate them.

As for dinos, Brusatte said, "Dinosaurs did live in other parts of Scotland at the same general time as this ichthyosaur was living in the water. We know this from other rare fossils from Skye -- bones, teeth and footprints of very different type of dinosaurs, including big long-necked sauropods and carnivorous theropods."

If any waded or fell into the shallow, warm seas where Dearcmhara lived, they likely would have been dinner for the stealthy ichthyosaur.

Nick Fraser of National Museums Scotland is excited by the discovery, and what it means for his country.

"Scotland is well noted for its geology and geologists, including perhaps the most famous of all, James Hutton (often dubbed the Father of Modern Geology, although he lived from 1726 to 1797)," Fraser told Discovery News. "However, it is not widely noted in the public realm for its fossils, which is unfortunate, as it boasts some incredibly important localities and specimens."

He explained that remains for prehistoric fishes and very early reptiles from the Triassic have been found in Scotland.

"Admittedly, there are not the huge rock exposures in Scotland that permit the excavation of spectacular death-beds of dinosaurs as you might find in the American West," Fraser said. "Yet, even some of the fragmentary remains that we do find are often of great scientific importance, and that is certainly the case with the Skye Jurassic fossils."

Fraser said that the remains represent a time period, the Middle Jurassic, which is rather poorly known worldwide in the fossil record. Evidence, however, from surrounding periods suggests that animal life then, in the seas and on land, was incredibly rich and diverse.

Read more at Discovery News

Did Meteorite Carve Icy Antarctic Crater?

Researchers in remote East Antarctica think a massive area of fractured ice discovered last month could be a newfound meteorite impact crater.

The mile-wide crater (about 2 kilometers across) is a circular scar marked by fractured, rumpled ice — a striking blot in this otherwise smooth section of Antarctica's King Baudouin Ice Shelf. It was spotted by German scientist Christian Müller during an aerial survey by plane on Dec. 20, 2014.

"I looked out of the window, and I saw an unusual structure on the surface of the ice," Müller said in a video describing the discovery. "There was some broken ice looking like icebergs, which is very unusual on a normally flat ice shelf, surrounded by a large, wing-shaped, circular structure," said Müller, a geoscientist with Fielax, a private company assisting Antarctic research.

The possible impact crater is about twice the size of Arizona's Barringer Meteor Crater. Satellite images suggest the broken-up ice could be at least 25 years old.

Lucky find

The crater was a serendipitous find, sighted by chance north of Belgium's Princess Elisabeth Research Station. German researchers at the station intended to remotely survey the surrounding bedrock, in order to gather new details on the Gondwana supercontinent's formation and breakup between 550 million and 180 million years ago. Flying over busted-up ice shelves — the floating extensions of the Antarctic Ice Sheet — was not part of the research plan.

"We were only flying that far in the north because the radar equipment had broken, and we didn't want to waste a good flying day," said Graeme Eagles, a scientist at Germany's Alfred Wegener Institute who is currently leading the geophysical research survey. "It's been a tremendously exciting couple of weeks," he added. "It really is a very raw form of science, with a lot of people speculating on what might or might not be the cause."

At first, Müller connected the crater to a 2004 meteor blast detected above this part of East Antarctica. Recently, however, the German research team discovered the crater in satellite images dating back to 1996, Eagles said. "The to the 2004 event really piqued our interest in the first place, but I don't think what we've seen in the satellite images rules out the possibility of an impact origin," Eagles told Live Science. "It just fuzzies the story a little bit."

Extraordinary claims

If a space rock did crash-land on the ice shelf, the meteorite was likely relatively large. Indeed, the crater's sheer size warrants skepticism, experts said.

As a rule of thumb, an object that formed a crater is usually about 10 to 20 times smaller than the crater itself, said Peter Brown, director of the Center for Planetary Science and Exploration at the University of Western Ontario in Canada. That means a 1.2-mile (2 km) crater would result from an object that measures roughly 325 feet (100 meters) across, Brown said.

"A very large explosion would have caused a 2-kilometer-wide crater — much larger than anything detected impacting Earth in recent history," Brown said. "So the feature seen is almost certainly not due to any meteorite impact."

Meteorite hunter Peter Jenniskens also found the crater idea implausible. "I don't think this is an impact crater," said Jenniskens, who holds dual affiliations at the SETI Institute and at NASA's Ames Research Center, both in California.

However, Eagles hinted that the German researchers have not shown all their cards. The scientists collected photos, video and data on a Dec. 26 trip to the crater site. The team mapped the ice surface in great detail with a laser-scanning instrument that records precise changes in topography. They also surveyed the area with a radar instrument that penetrates the upper surface of the ice and snow.

A number of smaller circular and subcircular structures were spotted nearby on this trip. The researchers haven't yet analyzed the data, but they hope to publish their results in a scientific journal if the structure is indeed an impact crater, Eagles said.

"This thing is very unusual indeed," Eagles said. "Extraordinary claims require extraordinary evidence, and in this case, as far as we can tell, is does look like it is extraordinary evidence."

Rock hunters

The researchers now must complete their Gondwana study before squeezing in any more trips to the crater, Eagles said. For instance, the team would like to eventually hunt for meteorites around the site.

Read more at Discovery News

Jan 11, 2015

Crowds, Leaders Gather for Historic Paris March of Defiance

Hundreds of thousands of people joined by world leaders flooded Paris on Sunday in a historic show of defiance and solidarity against terrorism following this week's Islamist attacks in the French capital.

As France mourned 17 victims of three days of bloodshed that included Jews and a Muslim police officer, the leaders of Israel and the Palestinian Authority were among those attending the mass rally.

Under blue skies, emotions were running high in the shell-shocked City of Light, with many of those gathering from all walks of life already in tears as they came together under the banner of freedom of speech and liberty.

Lassina Traore, a 34-year-old French-born Muslim from the Ivory Coast, gently placed 17 candles at the foot of the monument at the Place de la Republique, heaped with tributes to the dead.

The march is "a real sign of how strong France is. It shows that France is strong when she is united against these people," said the consultant.

"I want to show that we're not scared of the extremists. I want to defend freedom of expression," said 70-year-old Jacqueline Saad-Rouana.

The families of those who died in the shootings that shook France to its core will be at the very front of the march, leading royalty and heads of state.

Security was beefed up, with police snipers stationed on rooftops and plain-clothes officers among the crowd in a city still reeling from the Islamist attacks which left 12 staff and policemen dead at the Charlie Hebdo satirical magazine and claimed four lives at a Jewish supermarket. A policewoman was also killed.

"Today, Paris is the capital of the world," French President Francois Hollande said. "The entire country will rise up," he told ministers.

French Prime Minister Manuel Valls told a poignant rally on Saturday near where a gunman killed four hostages at the kosher store: "I have no doubt that millions of citizens will come to express their love of liberty, their love of fraternity."

In a foretaste of the demonstration, more than 700,000 people poured onto the streets of cities across France on Saturday, many carrying banners reading "Je suis Charlie" (I am Charlie), the tribute to Charlie Hebdo that has been the global rallying point in the wake of the slaughter.

Many brandished pens to symbolize freedom of expression after the magazine was targeted by brothers Said and Cherif Kouachi for publishing cartoons lampooning the Prophet Mohammed.

Along with Israel's Prime Minister Benjamin Netanyahu and Palestinian President Mahmud Abbas, the king and queen of Jordan were present alongside a host of top European leaders, including German Chancellor Angela Merkel and British Prime Minister David Cameron.

US President Barack Obama was represented by Attorney General Eric Holder, who took part in an emergency meeting of interior ministers to discuss the threats from Islamic extremism.

The ministers urged a strengthening of the EU external borders to limit the movement of extremists returning to Europe from the Middle East and said there was an "urgent need" to share European air passenger information.

Speaking on a visit to India, US Secretary of State John Kerry said: "We stand together this morning with the people of France. We stand together not just in anger and outrage but in solidarity and commitment in confronting extremists."

President Hollande, ahead of the march met representatives from the Jewish community who said authorities had agreed to even deploy soldiers to protect Jewish schools and synagogues "if necessary."

The rampage by three gunmen who claimed to be members of the Al-Qaeda and Islamic State extremist groups was followed by a chilling new threat from the Yemen-based Al-Qaeda in the Arabian Peninsula.

AQAP top sharia official Harith al-Nadhari warned France to "stop your aggression against the Muslims" or face further attacks, in comments released by the SITE monitoring group.

German newspaper Bild said the bloodshed in France could signal the start of a wave of attacks in Europe, citing communications by Islamic State leaders intercepted by US intelligence.

France's three days of terror started Wednesday when the Kouachi brothers burst into the Charlie Hebdo offices in central Paris and sprayed bullets into the editorial meeting, killing some of France's best-known cartoonists.

They then slaughtered a Muslim policeman as he lay helpless on the ground before fleeing, sparking a manhunt that lasted more than 48 hours.

A day later, a third gunman, Amedy Coulibaly, shot dead a policewoman in a southern Paris suburb.

In a video posted online Sunday, a man resembling Coulibaly said the gunmen coordinated their efforts and claimed he was a member of Islamic State who was avenging attacks by the international community on the extremist group.

Read more at Discovery News