Aug 1, 2015

British Viral 'Ghost Photo' Explained

A “ghost photo” taken by a British woman named Natasha Oliver is circulating in the news media and social media. It appears to be a human head and torso in an unfinished building in the background of a friendly gathering. The form is too dark and fuzzy to be identified, but some have claimed it looks like a ghostly mother and baby.

Oliver’s photo was taken five years ago but recently got widespread attention after she commented on a Facebook post about a ghost picture she thought was fake—and offered her own. The story was featured on “Good Morning America” today:
“Oliver said she and her friends “freaked out” after they saw the photo on her digital camera back in 2010, taken when they were hanging out on the lawn in front of the unfinished home still being built at the time. “When we saw the ghostly figure, the boys climbed up the scaffolding to see what was up there thinking maybe someone was watching us,” Oliver said. “But there was nothing up there. There were no floorboards or anything there. The house wasn’t finished being built yet at the time.”

While everyone loves a good ghost story, there are some reasons to be skeptical that a phantom photobombed their party picture. Though there was some speculation that the photo was faked—partly because a famous ghost photo from the same town claimed to be of a little girl killed in a fire was revealed to be a hoax—but a misunderstanding seems more likely in this case.

A Closer Look

It’s curious that there are only two, nearly identical photographs provided by Oliver, taken two minutes apart (at 21:20 and 21:22). If, as she claimed, the group immediately noticed that an odd figure seemed to be in the window behind them and a few friends were dispatched to investigate, it seems odd that there aren’t there more photos of it from a closer point of view.

Instead it seems that no one in the group even tried to get a better photo of it. A surprised exclamation of “Look! Is that a ghost?” during a review of a digital photograph taken moments before might be expected to result in a dozen cell phone cameras being produced to get their own photographic “proof” of the paranormal, but that did not happen.

In fact the additional photographic evidence provided by Oliver casts doubt on her explanation; because the photos are time-stamped, and because she uploaded dozens of photographs from that June 18 event to Facebook, there is a photographic record of what the group did after the “ghost photos” were taken.

The last image that shows the “ghost” was taken at 21:22, and is followed by 26 other photos depicting what the group did between that time and 21:52 that evening. There is not a single photograph that shows Oliver or any of her friends searching for a ghost—or even reacting to the discovery that they may have been in the presence of an undead spirit. Instead the two dozen photos show the group laughing, acting goofy, and enjoying an alcohol-fueled footballer party.

Role of Psychology and Memory

This part of the mystery is solved by a closer look at the photos, which reveals that four months elapsed before anyone noticed the ghostly figure; it seems to have been first noted on Oct. 4, 2010 by one of Oliver’s friends on Facebook. Therefore her quoted claim that “When we saw the ghostly figure, the boys climbed up the scaffolding to see what was up there thinking maybe someone was watching us” could not be true, since no one in her group saw the figure at the time, which explains why her photos show no investigation.

Since there was no investigation at the time—and therefore no one trying to figure out what the strange form might be—the claim that in looking for the ghost the creepy revelation that “there was nothing up there” can’t be accurate.

There are two second-story windows visible in the ghostly photograph; in another photo later in the series one of Oliver’s friends can be seen on scaffolding in front of one of the windows. Since the ghost wasn’t discovered until months later he was not (and could not have been) searching for the ghostly intruder; instead he is posing and holding a beer about half an hour after the “ghost” photo was taken.

He may have looked in the window and saw nothing—but he is at the wrong window. The ghost was photographed in the other window. What may have happened is that he told Oliver (months later) that when he had been up there he hadn’t seen anything odd and that there was nothing in that window, and he or she misunderstood which window he was referring to.

There’s no evidence that anyone even looked in the window where the “ghost” was photographed to see what was there.

Perhaps Oliver was misquoted and meant to suggest that, four months after the photo was taken they returned to search for a cause of the figure. But by then the construction would have likely been completed, the scene changed dramatically, and the scaffolding removed. Either way the story as it’s been presented cannot be accurate. A more likely explanation is that Oliver has simply misremembered the circumstances of that photo five years after it was taken.

Read more at Discovery News

How did Saturn Moon Tethys get Those Weird Stripes?

NASA’s Cassini mission has been orbiting Saturn for over a decade, so you’d be forgiven in thinking that it’s seen just about every weird feature on the ringed gas giant and its fascinating system of moons. But in new observations beamed back from Cassini, icy moon Tethys has only now decided to show off its mysterious stripes.

Using clear, green, infrared and ultraviolet spectral filters, during a flyby in April, Cassini’s cameras were able to create a color-enhanced view of the 660 mile (1,060 kilometer) wide ice-encrusted moon. And that’s when mission scientists saw them — long stripes of red discoloration arcing across the surface.

Although stripes that appeared slightly red have been spotted in previous flybys, the angle between the Saturnian system, the sun and Cassini has not been ideal. But as Saturn’s northern hemisphere has been entering summer these past few years, the northern stripes on Tethys have gradually come into view and now Cassini has recorded vivid red features that at first appear to be fairly young on geological timescales.

“The red arcs really popped out when we saw the new images,” said Cassini participating scientist Paul Schenk of the Lunar and Planetary Institute in Houston, Texas, in a NASA news release. “It’s surprising how extensive these features are.”

“The red arcs must be geologically young because they cut across older features like impact craters, but we don’t know their age in years.” added Cassini imaging scientist Paul Helfenstein, of Cornell University, Ithaca, New York. “If the stain is only a thin, colored veneer on the icy soil, exposure to the space environment at Tethys’ surface might erase them on relatively short time scales.”

Reddish bands are also found on Jupiter’s moon Europa, which is known to host a subsurface ocean. Europa’s streaks are colored by hydrated salts mixed with chemicals like magnesium sulfate or sulfuric acid. This chemistry is thought to be caused by a complex interplay between the liquid subsurface ocean and possible tectonics in Europa’s icy crust, leading to speculation about the possibility of a circulation of nutrients from the icy surface to the ocean below, potentially supporting an extraterrestrial biosphere.

Read more at Discovery News

Jul 31, 2015

Queen Bees Vaccinate All of Their Babies

Bee babies enter the world naturally vaccinated, according to a new study that found queen bees inoculate all of their young.

The scientists learned how queen bees manage this feat, and plan to replicate it in future with the hope of boosting bee immunity even more. The findings appear today in the journal PLOS Pathogens.

“The process by which bees transfer immunity to their babies was a big mystery until now,” co-author Gro Amdam of Arizona State University said in a press release. “What we found is that it’s as simple as eating. Our amazing discovery was made possible because of 15 years of basic research on vitellogenin. This exemplifies how long-term investments in basic research pay off.”

Co-author Dalial Freitak of the University of Helsinki added, “I have been working on bee immune priming since the start of my doctoral studies. Now almost 10 years later, I feel like I’ve solved an important part of the puzzle. It’s a wonderful and very rewarding feeling!”

The researchers explained that, in a honeybee colony, the queen rarely leaves the nest, so worker bees must bring food to her. Forager bees gather pollen and nectar, but in doing so, gather pathogens in the environment too. The whole mix, bacteria and all, is used back at the hive to create royal jelly, which the queen ingests.

Once consumed, the bacteria are digested in her gut and wind up stored in the queen’s “fat body,” which is an organ similar to a liver. Pieces of the bacteria are then bound to a protein called vitellogenin, and are carried via blood to the developing eggs. Because of this, bee babies enter the world vaccinated.

The simple brilliance of the process is that the bees are specifically safeguarded against diseases present in their own environment.

These days, however, bees face less predictable challenges from human activities, such as pesticide use and sudden widespread transfer of plants/crops and bee pests, as well as climate change factors and other threats. During the past six decades alone, managed honeybee colonies in the United States have declined from 6 million in 1947 to only 2.5 million today.

Armed with the new knowledge about vitellogenin, the scientists are working on the first ever edible and natural vaccine for beneficial insects like bees.

“We are patenting a way to produce a harmless vaccine, as well as how to cultivate the vaccines and introduce them to bee hives through a cocktail the bees would eat,” Freitak said. “They would then be able to stave off disease.”

Read more at Discovery News

Ebola Vaccine Gives 100 Percent Protection

An Ebola vaccine provided 100 percent protection in a field trial in hard-hit Guinea, researchers and officials said Friday, mooting “the beginning of the end” of the killer West African outbreak.

The world is “on the verge of an effective Ebola vaccine,” the World Health Organization (WHO) said, hailing the results from the first efficacy test of the VSV-ZEBOV vaccine among people living in a high-danger zone.

“This is an extremely promising development,” added WHO chief Margaret Chan.

“An effective vaccine will be another very important tool for both current and future Ebola outbreaks.”

About 28,000 people have been infected in Guinea, Sierra Leone and Liberia in the worst Ebola outbreak in history, according to the WHO, and more than 11,000 have died.

VSV-ZEBOV may become the first licensed vaccine against the disease for which there is also no approved treatment or cure.

The trial showed that the vaccine “offers 100 percent protection against Ebola after roughly one week,” said researcher Sven Trelle from the University of Bern.

The test, backed by drug firm Merck, the WHO and the governments of Canada, Norway and Guinea, saw 4,123 high-risk people vaccinated immediately after someone close to them fell ill with the deadly haemorrhagic fever.

None of the vaccinated group caught the virus, according to study results published in The Lancet medical journal.

A second, comparison group of 3,528 people received the vaccine only three weeks after potential exposure. Sixteen of them contracted the virus, said the study, but by day six after immunization, the remainder of this group was also fully protected.

“Indeed, no vaccinee developed symptoms more than six days after vaccination, irrespective of whether vaccination was immediate or delayed,” said the study paper.

“The initial results of the study show that the vaccine can effectively contain the further spread of the Ebola virus,” added a statement from the University of Bern, which contributed to the research.

Disease experts welcomed the results.

Read more at Discovery News

Volcanoes Share a Hotspot But Have Mysterious Differences

In the middle of the south Atlantic Ocean, the remote island of Tristan da Cunha — named after the Portuguese explorer who discovered it in 1506 — is best known for its active volcano, which paranormal enthusiasts claim has a mysterious human-like face in its mouth. About 250 miles away, the equally remote uninhabited island of Gough also has an active volcano.

Both volcanoes are connected to the same undersea volcanic mantle plume also known as a hotspot, a pipe-like structure that transports semi-molten rock from the Earth’s interior to the sea floor. But oddly, the hot material in each of the volcanoes has a different geochemical composition, which long has puzzled scientists.

But now a team of marine scientists and volcanologists from the GEOMAR Helmholtz Centre for Ocean Research Kiel, the University of Kiel and the University of London have an explanation. Though the two volcanoes are interconnected, they’re filled with material that comes from different parts of the Earth’s mantle, an 1,800-mile-thick layer of extremely hot, dense, semi-solid rock that exists between the Earth’s crust and its core.

They’ve discovered that plume beneath the two volcanoes, which formed some 132 million years ago as the supercontinent Gondwana broke up, drew material in the early phase of its existence from another geologic structure called a Large Low Shear Velocity Province, or LLSVP, which lies roughly 1,550 miles below the Earth’s surface. (From the U.S. Geological Survey, here’s an explanation of the Earth’s interior structure.)

“In its early stages, the plume only appears to have sucked in material from the LLSVP,” GEOMAR Professor Kaj  Hoernle, the study’s lead author, explained in an article on the GEOMAR website. “But over the course of time the LLSVP material at the NW side of the margin was exhausted and material from outside the LLSVP was drawn into the base of the plume.”

Read more at Discovery News

Magnetic Discovery Hints Why Earth Supports Life and Mars Doesn't

Earth’s magnetic field, which protects the planet from harmful blasts of solar radiation, is much older than scientists had previously thought, researchers say. In fact, this invisible, protective shield likely existed shortly after the planet formed — a finding that could shed light on why Earth is habitable and Mars is not.

Without Earth’s magnetic field, solar winds — streams of electrically charged particles that flow from the sun — would strip away the planet’s atmosphere and oceans. As such, Earth’s magnetic field helped to make life on the planet possible, researchers have said.

The magnetic field is generated by swirling liquid metal in Earth’s outer core, and this “geodynamo” requires the release of heat from the planet to drive its churning. Nowadays, this heat flow is aided by plate tectonics — the movement of the plates of rock that make up the planet’s exterior — which efficiently lets heat transfer from Earth’s interior to its surface.

Given the importance of Earth’s magnetic field, scientists want to pinpoint when it first developed, which could, in turn, provide clues about how the planet has been able to remain habitable and when plate tectonics began. However, when, exactly, plate tectonics originated is hotly debated, and some researchers argue that the early Earth lacked a magnetic field.

Since 2010, the best estimate of the age of Earth’s magnetic field was 3.45 billion years. In comparison, Earth is about 4.6 billion years old.

Now, scientists have found that Earth’s magnetic field could be up to 4.2 billion years old — about 750 million years older than had been previously thought.

The researchers investigated magnetically sensitive minerals such as magnetite, a naturally occurring cousin of rust. As molten rock cools, magnetite within it becomes literally set in stone, pointing to the location of Earth’s magnetic poles at the moment it froze. As a result, the oldest samples of magnetite can reveal the direction and intensity of Earth’s magnetic field at the earliest parts of Earth’s history, the researchers said.

The scientists analyzed magnetite samples trapped in tiny, ancient zircon crystals that were collected from the Jack Hills in Western Australia. To detect the magnetic fields, the scientists had to have a special magnetic sensor built that was 10 times more sensitive than other instruments used to make these kinds of measurements.

Isolating the zircons from the surrounding rock was challenging. “Typically, we separate zircons out using high magnetic fields, but we couldn’t do that here, since it would destroy what information they had,” said John Tarduno, a geophysicist at the University of Rochester in New York and lead author of the new study detailing the findings. “So we had to separate thousands of zircons out by hand, cleaning them in mild acids, which took a huge amount of time,” Tarduno told Live Science.

Then, to get reliable measurements, the researchers had to make sure the samples they analyzed never got hot enough after they formed to allow the magnetic information recorded within to reset. The researchers found that the minerals were pointed in a variety of magnetic directions, which suggested the samples were pristine.

“f the magnetic information in the zircons had been erased and re-recorded, the magnetic directions would have all been identical,” Tarduno said in a statement.

The intensity of the magnetic fields that the samples recorded suggests the presence of an ancient geodynamo, the researchers said.

These findings likely indicate that Earth had a magnetic field, and plate tectonics, since very early in its history.

“It’s surprising, because some of the models of the ancient Earth suggest that a magnetic field or plate tectonics could not have occurred that early,” Tarduno said. “Those models need to be rethought to include potential ways of cooling Earth’s interior early on.”

This ancient magnetic field could be a key reason Earth is still habitable and Mars was unable to sustain life, as far as we currently know.

Read more at Discovery News

The Two-Foot-Wide Sea Star That’s Basically a Bear Trap

Labidiaster annulatus kinda looks like a regular sea star fell off a skyscraper and splatted.
Few oceanic creatures are as iconic and beloved as the sea stars (which, fun fact, are collectively known as “asteroids,” which only makes them that much cooler). They’re just so simple, so quaint, so … star-like. Hell, slap a pair of googly eyes on one and it’d be downright cute. Yet these are actually voracious scavengers, hoovering up whatever meat they happen upon on the seafloor. And a few species even go one step further: They’re hunters—sluggish but accomplished hunters.

Reigning among them is Labidiaster annulatus, a two-foot-wide titan that menaces the waters around Antarctica. Not content with just scavenging, and not even content with just hunting creatures on the seafloor like other sea stars, it can actually pick off fish swimming in the water column. Sounds far-fetched, I know, but stick with me here. Or don’t. I’m not your father.

These things are really, really successful down there in Antarctica. “They form this sort of Lovecraftian benthic landscape,” says marine biologist Christopher Mah of the Smithsonian, who’s the guy to talk to about sea stars, “because they tend to crawl up onto perches or sponges or any kind of elevated perch and hold their arms up in the water to take advantage of the food. So that could be anything natural such as a sponge to seismic sensors.” Mah knows this, by the way, because a geologist once sent him an email asking what the hell a giant sea star was doing on top of one of his devices.

Now, the classical notion of sea stars is that they’re supposed to have five rays, and indeed they all start out with five. Clearly, though, Labidiaster annulatus scoffs at this rule. As it grows, it adds ever more rays in between those original five until it ends up with more than 50. That’s 50 weapons to wield against its prey.

So, it perches itself on a sponge or seismic sensor or what have you and puts its hands in the air like it just don’t care, usually the majority of its rays at any given time. There it waits for hapless swimmers—crustaceans like krill, say—to come along and bump into it, sticking fast to the many jaws that coat the sea star. Think of it like how a jellyfish hunts, only much more toothy.

“[The claws] are very nasty and formidable looking,” says Mah. “They look like bear traps. And they function very much the same way. There are these big, jagged teeth, and as soon as a krill impacts upon them the claws just snap shut and grab them.”

Oh hey look a thing that will stalk my dreams for the next decade.
These claws are formally known as pedicellariae, and the sea star is positively covered in them. Running along its arms are fleshy bands called annuli, each loaded with as many as 80 pedicellariae, so there aren’t many places on the creature that aren’t capable of snagging prey. When it does grab something, it’ll bend in other arms to help subdue the victim, kind of like an octopus (it’s unusually flexible for a sea star—maybe it’s into yoga, I dunno). Then, using little structures called tube feet, the sea star starts conveyor-belting the victim into its mouth, where it’s swallowed whole and very much alive.

Other sea stars, such as the ochre star, have pedicellariae as well, but nothing has pedicellariae as big as Labidiaster annulatus. “I’ve had experiments where you’ll take some big hairy guy,” says Mah, “and you put a sea star arm against their forearm and you pull back and the sea star is attached like velcro to the guy’s arm hair. And so [Labidiaster annulatus] would be worse.”

“If they were five feet across we’d be running from them,” he adds, “because they’re not very friendly looking animals when you look at them up close.”

A closeup of the pedicellariae. They kind of look like the jaws of the bugs in Starship Troopers, only, you know, they’re not computer-animated.
As long as the prey’s the right size, there isn’t much the sea stars won’t take on. Judging by stomach contents, they seem to be particularly fond of the aforementioned krill, but will from time to time tackle fish and even run down their own kind. One Labidiaster annulatus that scientists hauled aboard a ship disgorged brittle stars on deck, alive and well save for a missing limb here or there.

Thus does Labidiaster annulatus dominate the Antarctic ecosystem. Really, its echinoderm kin as well as other invertebrates dominate the ecosystem as a whole. And this is a bit goofy. A tropical reef, say, is ruled by vertebrates: sharks and other fish. Fish in particular are bad news for sea stars—Labidiaster annulatus waving its long arms around in a reef would just be asking to get amputated. But fish are in short supply in these frigid waters—save for a very special variety that has antifreeze for blood—so sea stars and other invertebrates have ascended the throne. (Labidiaster annulatus is joined here by another giant, the ribbon worm, which grows to six feet long and has a similarly unrestrained diet. Researchers testing what it would eat started to run out of ideas, so they gave it tomato sauce. It liked that too.)

“This is what’s called a Paleozoic-style ecosystem, one where the invertebrates are actually the dominant ones,” says Mah. “This is in reference to the Paleozoic, before fish evolved, and you have this system dominated by soft bodied organisms such as cephalopods and worms and so forth.”

Read more at Wired Science

Jul 30, 2015

Plants Release Animal-like Substance When Stressed

Although plants do not have nervous systems, they respond to stress with chemical and electrical signals that are remarkably similar to those of animals, a new study has found.

The findings, published in the journal Nature Communications, could help to explain why certain plant-derived drugs work so well in humans.

At the center of it all is the neurotransmitter GABA (gamma-aminobutyric acid), which humans and animals, as well as plants, release when they are stressed out.

“We’ve known for a long time that the animal neurotransmitter GABA is produced by plants under stress, for example, when they encounter drought, salinity, viruses, acidic soils or extreme temperatures, but it was not known whether GABA was a signal in plants,” senior author Matthew Gilliham of the University of Adelaide’s School of Agriculture, Food and Wine said in a press release.

He continued, “We’ve discovered that plants bind GABA in a similar way to animals, resulting in electrical signals that ultimately regulate plant growth when a plant is exposed to a stressful environment.”

Co-author Stephen Tyerman is optimistic that the discovery could lead to new ways of modifying how plants respond to stress. He explained that most yield losses from agricultural crops come from “major stresses” like pathogens and poor environmental conditions. If the plants succumb to these threats, food shortages may result.

Tyerman further explained that by “identifying how plants use GABA as a stress signal, we have a new tool to help in the global effort to breed more stress-resilient crops to fight food insecurity.”

The researchers suspect that GABA and its interaction with neurotransmitters evolved independently in the plant and animal kingdoms. This is because, while the proteins share many characteristics in common, some aspects of these same proteins are different between plants and animals.

Nevertheless, since the basic GABA signaling system exists within both groups, particular plant-derived drugs and other plant-based products often match well with our health needs. For example, chamomile is thought to bind to GABA receptors, acting as an inhibitory neurotransmitter. As a probable result, this natural ingredient tends to provide a gentle, natural feeling of calmness when consumed.

Read more at Discovery News

Everglades Python May Be Second-Largest Ever in Florida

A python researcher working in Everglades National Park has captured what may be the second-largest Burmese python in the state of Florida, CBS Miami reports.

The snake was captured on July 9 in the park's Shark Valley and was documented at 18 feet 3 inches long. It's just 4 inches shy of the state's record 18 foot 7 inch python caught in Miami-Dade, CBS notes. Whether it's indeed the second-largest, officially, remains unclear, due to differences in record-keeping in and outside of the park.

Florida has struggled to contain the pythons, which lack a natural predator and wreak havoc with small mammal populations in the park.

The snake, a female, was euthanized, park officials said.

There could be more than 100,000 Burmese pythons in South Florida. Native to Asia, it exists in Florida thanks to an international pet trade that started decades ago, according to CBS.

From Discovery News

2000-Year-Old Cat Paw Prints Discovered on Tile

Paw prints made by a cat 2,000 years ago have been found on a Roman roof tile kept at a museum in south west England.

Dug up in Gloucester in 1969, the tile fragment had long lain unnoticed at Gloucester City Museum.

Only recently, a researcher spotted the cat’s paw on the tile while going through the finds from the 1969 archaeological excavation.

“At that time the archaeologists seem to have been more interested in digging things up than looking at what they found,” David Rice, curator at Gloucester City Museum, told Discovery News.

The cat is thought to have run across the wet clay tile when it was left out to dry in about AD100.

Despite the feline footprints, the Romans fired the tile, a type called tegula, and used it on the roof of a building in what became the Berkeley Street area of modern Gloucester.

It is possible the cat was a Roman army cat, the pet of a Roman soldier who stationed at the site.

The tile is now on display at the Gloucester City Museum and Art Gallery.

“The marks are the only example for Roman domestic cats that visitors can see in the museum,” Rice said.

“I believe there are more cat paw prints found on ancient Roman tiles in Britain than anywhere else in the Roman Empire including Italy. Roman Britons must have had a special liking for cats,” he added.

From Discovery News

Fossil Fuels May Be Screwing Up Carbon Dating

Radiocarbon dating has been helping put the planet’s history in the right order since it was first invented in the 1940s, giving scientists a key way to determine the age of artifacts like the Dead Sea Scrolls and the Shroud of Turin.

Thanks to fossil fuel emissions, though, the method used to date these famous artifacts may be in for a change.

The burning of fossil fuels is altering the ratio of carbon in the atmosphere, which may cause objects tested in the coming decades to seem hundreds or thousands of years older than they actually are, according a study published in the Proceedings of the National Academy of Sciences.

A cotton T-shirt manufactured and tested in 2050 may appear to be the same age as an artifact from the 11th century when dated using the radiocarbon method. A new shirt made in 2100, if emissions continue unabated, could appear to come from the year 100, alongside something worn by a Roman soldier.

In short, future human emissions may alter one of the most reliable methods for learning about the past.

Radiocarbon dating relies on the amount of radiocarbon, or carbon-14, remaining in an object to determine its approximate age. Radiocarbon is a radioactive form of carbon that’s created when nitrogen reacts with cosmic rays in the upper atmosphere. It occurs only in trace amounts, but it is present in every living thing.

Carbon-14 can combine with oxygen in the atmosphere to create carbon dioxide, which is then absorbed by plants and makes its way through the food chain. The amount of carbon-14 in living plants and animals matches the amount in the atmosphere, but when plants and animals die, they no longer absorb carbon-14.

Because radiocarbon has a known rate of decay, scientists can determine about how long it has been since the plant or animal was alive. The lower the amount of radiocarbon, the older the object.

But big changes in the atmosphere can throw off this method, like releasing tons of extra carbon dioxide into the air from burning fossil fuels. Because fossil fuels like coal and oil are so old, they have no radiocarbon left. When burned, they increase the amount of carbon dioxide, which dilutes the radiocarbon in the atmosphere and the amount that can be absorbed by organic material.

“Fossil fuels have lost all of their radiocarbon over millions of years of radioactive decay,” said Heather Graven, author of the study published last week. “This makes the atmosphere appear as though it has ‘aged.’”

Scientists are used to a bit of wiggle with carbon-14 dating; it can vary as much as 30 to 100 years from the actual age. But the changes from emissions will require some extra adjustment, even in the study’s best-case-scenario emissions projection.

Read more at Discovery News

Monstrous Aurora Detected Beyond our Solar System

For the first time, astronomers have detected an aurora erupting beyond the solar system, giving us a profound glimpse at the magnetism surrounding a brown dwarf, or “failed star.”

Until now, the only aurorae astronomers have witnessed have been located on planets within our own star system. The sun produces a steady stream of electrically charged particles, called ions, that wash throughout the solar system as the solar wind and intermittent coronal mass ejections. These ions go on to interact with planetary magnetic fields and atmospheres to generate beautiful lightshows.

In the case of Earth, powerful geomagnetic storms can be triggered when the sun’s magnetic field, loaded with ions, interacts with our global magnetosphere. Should this happen, ions from the sun are funneled into higher latitudes, which then interact with our atmosphere, generating Northern and Southern Lights — the Aurora Borealis and Aurora Australis, respectively.

Likewise, aurorae have been observed on Jupiter, Saturn and other planets in the solar system that possess a magnetic field and atmosphere.

Now astronomers have confirmed the first ever “exo”-aurora, an aurora erupting on a celestial object well beyond the confines of our solar system. But the most fascinating thing about this discovery is that this aurora wasn’t detected at an exoplanet, it was detected at a brown dwarf.

“All the magnetic activity we see on this object can be explained by powerful auroras,” said Gregg Hallinan, of the California Institute of Technology (Caltech), in a news release. “This indicates that auroral activity replaces solar-like coronal activity on brown dwarfs and smaller objects.”

Brown dwarfs are a mysterious class of object that forms a bridge between stars and planets. They possess characteristics of both, but cannot be clearly defined as either. As they are lower mass objects than stars that maintain nuclear fusion in their core, brown dwarfs are often referred to as “failed stars” — they are not massive enough to sustain fusion for long periods of time.

But what brown dwarfs lack in the fusion department, they certainly seem to make up for in the aurora department; the aurora detected on brown dwarf LSR J1835+3259 is 10,000 times more powerful than any planetary aurora we have detected previously.

LSR J1835+3259 is located 18 light-years from Earth and the radio signal generated by its aurora was detected by the Karl G. Jansky Very Large Array (VLA) in New Mexico. Optical measurements of the brown dwarf by the 5-meter Hale Telescope on Palomar Mountain, Calif., and the 10-meter Keck Telescope in Hawaii were also able to characterize the object. These observations have found that brown dwarfs support extremely powerful auroral activity, much stronger than planetary magnetic fields, but weaker than the coronal magnetic activity that can be found in more massive stars like our sun.

Read more at Discovery News

Jul 29, 2015

NASA's Curiosity Rover Eyes Weird Rock on Mars

NASA’s Mars rover Curiosity went out of its way to investigate a rock the likes of which it has never seen before on the Red Planet.

Measurements by Curiosity’s rock-zapping ChemCam laser and another instrument revealed that the target, a chunk of bedrock dubbed Elk, contains high levels of silica and hydrogen, NASA officials said.

The abundance of silica — a silicon-oxygen compound commonly found here on Earth in the form of quartz — suggests that the bedrock may provide conditions conducive to the preservation of ancient carbon-containing organic molecules, if any exist in the area, the officials added. So Curiosity’s handlers sent the rover back 151 feet (46 meters) to check Elk out.

“One never knows what to expect on Mars, but the Elk target was interesting enough to go back and investigate,” ChemCam principal investigator Roger Wiens, of Los Alamos National Laboratory in New Mexico, said in a statement.

Elk lies near a spot on the lower reaches of the 3.4-mile-high (5.5 kilometers) Mount Sharp, called Marias Pass, whose rocks Curiosity had been studying. Marias Pass is a “geological contact zone” where dark sandstone meets lighter mudstone.

“We found an outcrop named Missoula where the two rock types came together, but it was quite small and close to the ground,” Curiosity project scientist Ashwin Vasavada, of NASA’s Jet Propulsion Laboratory in Pasadena, California, said in the same statement. “We used the robotic arm to capture a dog’s-eye view with the MAHLI [Mars Hand Lens Imager] camera, getting our nose right in there.”

ChemCam had fired at the Elk bedrock from the top of a small hill close to Marias Pass, which Curiosity had summitted before taking a look at the contact zone. After looking at the Missoula outcrop, the 1-ton rover began moving on, but an analysis of ChemCam’s data persuaded the team to turn Curiosity around for a closer look at Elk, mission team members said.

“ChemCam acts like eyes and ears of the rover for nearby objects,” Wiens said.

As Curiosity gathers data, mission engineers continue to investigate a short circuit that cropped up in the rover’s sample-collecting drill in February. No short circuits occurred during a July 18 engineering test, so the Curiosity team plans to conduct some drilling trials on rocks in the near future, NASA officials said.

Read more at Discovery News

X-Ray Reveals Mysterious Component of Human Hair

A new and surprising component of human hair has just been discovered, according to research that will be presented today at the annual meeting of the American Crystallographic Association, held in Philadelphia.

Human hair has been extensively studied for decades, but until now, a complete understanding of its structure had proven elusive.

"Hair traditionally has been constituted of three regions: medulla (central part of the hair), cortex (biggest volume fraction of the hair) and the cuticle (external part of the hair)," project leader Vesna Stanic, a scientist working at the Brazilian Synchrotron Light Source, told Discovery News.

"We discovered a new intermediate zone, which is in between the cuticle and cortex," she added.

Stanic and her team made the discovery by combining an ultra powerful submicron X-ray beam with cross-sectional geometry. The original goal was to just study materials used in hair treatments, and how they affect hair. While doing this, Stanic wondered about the diffraction patterns of hair.

Diffraction is the bending of waves around obstacles and openings. X-ray diffraction patterns of a given material can therefore reveal the local arrangement of both molecular and atomic structures.

Diffraction patterns of human hair have been documented before, but they usually involved pointing the X-ray beam perpendicular to the hair fiber axis. Stanic and her team decided to do something different.

"We performed a full diffraction map from a 30-micron-thick cross section of hair, with an incident beam parallel to the hair axis, and then compared it to the diffraction map with the beam perpendicular to the hair axis," she explained.

Before this study, human hair was thought to be composed only of a fibrous protein called alpha keratin, as well as certain minerals and lipids. The scientists were therefore extremely surprised to find that a key diffraction feature of alpha keratin was absent in the area between a hair strand's cuticle and cortex. The pattern instead corresponded to beta keratin.

Previously, beta-keratin was associated with reptiles and birds. It is what makes claws, scales, beaks and feathers strong, tough and, in the case of feathers, also flexible and elastic.

Alpha and beta keratin are similar molecules, but they have very different sizes and shapes.

Stanic explained, "The basic difference between alpha and beta keratin is the molecule conformations. We can say that beta keratin is essentially stretched alpha keratin. Alpha keratin has a helical structure, while beta is typically arranged in sheets."

The discovery comes on the heels of other research helping to explain why humans from different parts of the world have distinctive hair types. The reason can be summed up in one word: Neanderthals.

Daven Presgraves, an associate professor in the Department of Biology at the University of Rochester, told Discovery News that people of non-African heritage today retain Neanderthal alleles (alternative gene types) at genes affecting keratin filaments.

"The implication is that these Neanderthal-derived alleles were particularly well adapted to Eurasian environments in which they'd evolved for several hundred thousands of years," Presgraves told Discovery News. "Modern humans who interbred with Neanderthals on their way out of Africa were, in effect, able to borrow these keratin-associated alleles, perhaps accelerating adaptation to a Eurasian environment that was new to them."

Read more at Discovery News

Cassini to Make Final Flybys of 2 Icy Saturn Moons

For the next six months, NASA’s Saturn-orbiting Cassini spacecraft will get its final look at two icy moons — one famous and one not so well-known. It will fly by the erupting moon Enceladus three times, checking out its plumes in the best detail to date. And it will take one last look at the moon Dione (pronounced die-OWN-ee), which may have eruptions as well.

Why are icy moons so interesting to astronomers? One reason is they represent some of the best chances of finding life in our solar system. Many of these icy moons are believed to host global oceans underneath. Warmed by gravitational interactions with massive Saturn, there could be microbes floating under the surface just waiting for us to examine.

The long last look at Dione will take place Aug. 17, when Cassini will do gravitational measurements to learn more about its interior and icy shell. “There are intriguing hints that perhaps there’s something similar going on on Dione that we might have on Enceladus, but we haven’t found the equivalent of a smoking gun,” Linda Spilker, the Cassini project scientist at NASA’s Jet Propulsion Laboratory, told Discovery News.

The plumes on Enceladus were first found from measurements by Cassini’s magnetometer, which recorded evidence that the magnetic field lines do not go down to the surface — as is what would be expected on an airless body.

But similar evidence is so far lacking at Dione. Perhaps it’s because the moon is bigger, Spilker says, meaning the plumes are pulled down by gravity and are harder to see. Scientists will also look at Dione from afar in 2017, when the moon passes in front of a background star. If there are plumes erupting from Dione, it would dim the starlight.

As for Enceladus itself, three final flybys are planned in 2015 to learn more about its environment: a view of the north pole on Oct. 14, a “plunge” into the known location of a plume Oct. 28, and an attempt to look at the thermal environment of the south pole Dec. 19.

It’s now winter time in the south pole of Enceladus, providing a unique opportunity to look at any heat coming from the “tiger stripes” in that region. These zones are associated with the icy plumes that are coming from Enceladus.

The north pole flyby will allow them to use a “high phase angle” to examine the plumes in more detail; it’s sort of the equivalent of driving into the sun with the dust on the windshield, Spilker said, because the sun reflects off the dust. This allows them to measure how the plumes have changed.

And the most spectacular of the trio of flybys will be going deep into a known plume region itself, to measure the gas and particles and learn more about their source. The working theory is that water from the sea floor of Enceladus goes through the cracks below the surface, interacts with the rocky core and heats up, then erupts back above the surface and interacts with colder water. Nanosilica particles have been detected in the plumes, which occur in the presence of hot water.

These regular flybys of moons are possible through interactions with the massive Titan, one of the larger moons in the solar system (almost as big as the planet Mercury) and also of interest because it has an ecosystem full of ethane and methane. Its liquid lakes make it unique in the solar system. So Cassini does observations of this intriguing world while taking advantage of its gravity to slingshot to other locations.

Read more at Discovery News

Stellar Mystery Solved: Exploding Star is a Lithium Factory

Lithium has been detected in stellar material blasting away from an exploding star, possibly revealing the source of the basic element in young stars, thereby solving a mystery that has perplexed astronomers for decades.

The event, known as a nova, occurred in southern skies in December 2013 near the bright star Beta Centauri. A nova is thought to occur in binary star systems where a white dwarf star pulls hydrogen from its binary partner. Once this material reaches a critical mass, the hydrogen undergoes a runaway fusion reaction, causing the white dwarf to erupt.

It has long been known that novae can produce an array of different chemical elements that enrich the interstellar medium with gases that go on to help form later generations of stars. However, though lithium is theorized to also be produced by these explosions, astronomers have not been able to detect any trace of the element in previous novae.

Lithium is one of the few elements that is thought to have been produced by the Big Bang, nearly 14 billion years ago. However, astronomers have observed a greater abundance of lithium in younger stars than older stars, indicating there must be another production mechanism in the modern universe.

So, in the 1970s, astronomers’ attention shifted to novae as being the culprit. Although rare, and much less powerful than their larger supernova cousins, it was thought that over the history of the Milky Way enough novae likely occurred to explain this abundance of lithium. But observations of novae seeking elusive lithium proved fruitless.

Then Nova Centauri 2013 (also known as V1369 Centauri) lit up our skies, an explosion that was easily visible to the naked eye and the brightest nova so far this century.

As reported in a new study published Wednesday in the Astrophysical Journal Letters, Luca Izzo, from Sapienza University of Rome and ICRANet, Pescara, Italy, and his team used the FEROS instrument on the MPG/ESO 2.2-meter telescope at the La Silla Observatory in Chile, and the PUCHEROS spectrograph on the ESO 0.5-meter telescope at the Observatory of the Pontificia Universidad Catolica de Chile near Santiago, to zoom in on V1369 Centauri.

These new data have revealed a “very clear signature” of lithium speeding away from the stellar explosion at a speed of 2 million kilometers (1.2 million miles) per hour, the first time lithium has ever been seen being produced by a nova.

Read more at Discovery News

LHC Keeps Bruising 'Difficult to Kill' Supersymmetry

In a new blow for the futuristic "supersymmetry" theory of the universe's basic anatomy, experts reported fresh evidence Monday of subatomic activity consistent with the mainstream Standard Model of particle physics.

New data from ultra high-speed proton collisions at Europe's Large Hadron Collider (LHC) showed an exotic particle dubbed the "beauty quark" behaves as predicted by the Standard Model, said a paper in the journal Nature Physics.

Previous attempts at measuring the beauty quark's rare transformation into a so-called "up quark" had yielded conflicting results. That prompted scientists to propose an explanation beyond the Standard Model -- possibly supersymmetry.

But the latest observations were "entirely consistent with the Standard Model and removes the need for this hypothesis" of an alternative theory, Guy Wilkinson, leader of LHC's "beauty experiment" told AFP.

"It would of course have been very exciting if we could show that there was something wrong with the Standard Model -- I cannot deny that would have been sensational," he said.

The Standard Model is the mainstream theory of all the fundamental particles that make up matter, and the forces that govern them.

But the model has weaknesses: it doesn't explain dark matter or dark energy, which jointly make up 95 percent of the universe. Nor is it compatible with Einstein's theory of general relativity -- the force of gravity as we know it does not seem to work at the subatomic quantum scale.

Supersymmetry, SUSY for short, is one of the alternatives proposed for explaining these inconsistencies, postulating the existence of a heavier "sibling" for every particle in the universe.

This may also explain dark matter and dark energy.

'Many-Headed Monster'

But no proof of supersymmetric twins has been found at the LHC, which has observed all the particles postulated by the Standard Model -- including the long-sought Higgs boson, which confers mass to matter.

Supersymmetry predicts the existence of at least five types of Higgs boson, but only one, believed to be the Standard Model Higgs, has so far been found.

Wilkinson said it was "too soon" to write off supersymmetry.

"It is very difficult to kill supersymmetry: it is a many-headed monster," he said.

But "if nothing is seen in the next couple of years, supersymmetry would be in a much harder situation. The number of true believers would drop."

Quarks are the most basic particles, building blocks of protons and neutrons, which in turn are found in atoms.

There are six types of quarks -- the most common are the "up" and "down" quarks, while the others are called "charm", "strange", "beauty" and "top."

The beauty quark, heavier than up and down quarks, can shift shape, and usually takes the form of a charm quark when it does.

Much more rarely, it morphs into an up quark. Wilkinson's team have now measured -- for the first time -- how often that happens.

"We are delighted because it is the sort of measurement nobody thought was possible at the LHC," he said. It had been thought that an even more powerful machine would be needed.

The revamped LHC, a facility of the European Organisation for Nuclear Research (CERN), was restarted in April after a two-year revamp to boost its power from eight to 13, potentially 14, teraelectronvolts (TeV).

Read more at Discovery News

Jul 28, 2015

Just One Animal Today Has Teeth Like T. rex

Tyrannosaurus rex and other large meat-loving dinosaurs had deeply serrated teeth that let them tear through the flesh and bone of victims.

Only one animal living today has this same tooth structure, according to new research, published in the journal Scientific Reports. The Komodo dragon, which is the world’s largest lizard, holds that distinction.

“What is so fascinating to me is that all animal teeth are made from the same building blocks, but the way the blocks fit together to form the structure of the tooth greatly affects how that animal processes food,” project leader Kirstin Brink of the University of Toronto Mississauga’s Department of Biology, said in a press release.

Brink and her colleagues used both a scanning electron microscope and a synchrotron, which can identify a substance’s chemical composition, to analyze tooth slices from eight meat-eating dinosaurs, such as T. rex, Allosaurus, Coelophysis and Gorgosaurus.

The investigations revealed that the serrations on the teeth of these bloodthirsty predators were supported by tissues inside of each tooth. The arrangement of these tissues reinforced the serrations all the more, making the teeth more efficient at biting through bones and ripping flesh.

As a result, it was a dinosaur-eat-dinosaur world, since the strong teeth and other adaptations allowed these now-extinct animals to take down very large prey. Before carnivorous dinos died out (dinosaurs that were not birds, that is), they prospered for about 165 million years as the planet’s top terrestrial predators.

Komodo dragons, which are native to Indonesia, can kill large prey too, including humans and 1,200-pound water buffalos. Komodo dragons also produce a venom that can prevent their victim’s blood from clotting. Before the venom was discovered by scientists, animal experts used to think that bacteria harbored in the mouths of Komodo dragons helped to kill prey.

Brink and her team determined that, in the dinosaur teeth, the unique arrangement of interior tooth tissues did not develop in response to the carnivores chewing hard materials. They came to that conclusion after examining samples of dinosaur teeth that had not yet broken through the gums when the animals died. They also looked at samples from mature dinosaur teeth.

Read more at Discovery News

Antiquities Found on Shipwreck That Carried Elgin Marbles

Lord Elgin collected other Greek antiquities besides the sculptures taken from the Parthenon, finds a new survey at the site of the British ship Mentor, which sank off southern Greece more than 200 years ago carrying marbles from the Acropolis to London.

During a two-week search that ended on July 12, Greek Culture Ministry divers explored the wreck of the Mentor, off the island of Kythera and found three ancient handles of Rhodian amphoras and a small stone vessel. The handles date to the 3rd century B.C. and belong to jars made in the island of Rhodes. Two are stamped.

The findings confirm the theory that other antiquities besides the Partenon marbles were aboard the ship.

The shipwreck has been investigated by underwater archaeologists since 2009 in the hope of finding other Parthenon marbles.

The ship was loaded with 16 crates of marble art removed from the Acropolis on behalf of Thomas Bruce, the Scottish Earl of Elgin. En-route to Malta and then the United Kingdom, the ship sank in 1802 during a storm at the entrance of the port of Avlaimona, on the island of Kythera.

Recovered soon after the sinking, the sculptures are now displayed with other Parthenon Marbles in London’s British Museum. They are at the center of a long standing cultural dispute between Greece and Britain.

Greece contends that the 17 figures and 56 panels that once decorated Athens’ most sacred shrine, the Parthenon, were stolen in 1801 by Lord Elgin, the British Ambassador to the Ottoman Empire between 1799 and 1803. Britain claims that Lord Elgin had received permission from the Ottoman Empire to take the marbles.

As with the other explorations, the July underwater excavation aimed at establishing whether there are still remnants of artworks near the ship.

“This year the excavation focused on the western boundary of the surviving portion of the hull, towards the bow, where two fragments of Egyptian sculptures were found in 2013,” the Greek Culture Ministry said in a statement.

Carried out with the support of the Kytherian Research Group, an Australian foundation, and under the direction of archaeologist Dimitrios Kourkoumelis, the excavation concentrated on a 17 by 17-foot area.

Read more at Discovery News

Mysterious Jamestown Burials Identified as Founders

Four lost leaders of the first permanent English settlement in the Americas have been identified, thanks to chemical analysis of their skeletons, as well as historical documents.

The settlement leaders were mostly high-status men who were buried at the 1608 Jamestown church in Virginia. And all played pivotal roles in the early colony.

“They’re very much at the heart of the foundation of the America that we know today,” said Douglas Owsley, a forensic anthropologist at the Smithsonian Institution in Washington, D.C., who helped identify the bodies.

By analyzing the bones, researchers can get a snapshot of what it was like to live during the earliest days of America, Owsley said.

“It’s a way of getting very detailed information you simply can’t get from the history books,” Owsley told Live Science.

First colonies

Though the British had previously sent out settler ships (to the doomed colony of Roanoke), the British colonial adventure in America truly got started in Jamestown, Virginia.

English settlers disembarked from their ships in 1607 at an inland spot along the James River, marking a chunk of land as a prime location for a fortified settlement. Over the next few years, several boats would arrive, bearing hundreds of settlers to what would be called Jamestown.

But times were rough; during a six-month period in 1609 known as the “starving time,” nearly 250 people died at Jamestown. At least some of the inhabitants resorted to cannibalism, according to a 2013 study by the same researchers.

Founding fathers

In 2013, Owsley and his colleagues first unearthed the bodies, near the historic Jamestown church where Captain John Smith married Pocahontas. Two of the bodies were in fairly ornate, anthropomorphic coffins, though the bodies were poorly preserved.

To identify the men, the archaeologists combined genealogical and historical documents from both England and the colonies, along with artifacts and analyses of the chemicals in the skeletons. For instance, the elite often had higher levels of lead in their bones during this time, because they frequently used lead-containing pewter and lead-glazed ceramics for eating and drinking, Owsley said.

“These are high-status individuals, two of them particularly so,” Owsley told Live Science.

One of the men was Ferdinando Weyman, who died in 1610 at around age 34. He was the uncle of Sir Thomas West, the governor of Virginia. Weyman was also related to another of the men identified, Captain William West. This man perished in 1610 after a fight with the Powhatan Indians. His body was identified thanks to a partly decayed, dirt-covered military sash that was found with the skeleton. The sash, still inside a block of dirt, was placed in a computed tomography (CT) scanner, which revealed a silk cloth decorated with silver fringe.

Both West and Weyman were buried in human-shaped coffins with a distinctive pattern of nails. Weyman had higher lead levels in his bones than the other individuals, indicating his elite status.

Another of the newly identified men was Captain Gabriel Archer, who died during the starving time in 1609 at the age of 34. Captain Archer was buried with the leading staff, an arrow-tipped staff that he used, enabling the team to identify him. Archer was also buried with a small silver box, known as a reliquary, containing bone fragments and pieces of a lead container for holding holy water atop his coffin. The artifact suggests he may have secretly clung to his Catholic faith.

The last man of the group was Reverend Robert Hunt. Unlike the more affluent men, he was buried in a simple shroud, facing west, toward the congregation he headed. Hunt died in 1608 around the age of 39.

Lost to history

The research team may do further analysis to confirm the men’s identities. The bodies were poorly preserved, but it may be possible to extract some usable DNA from the remains, Owsley said.

“Even as we speak, we’re looking at genetic evidence to see if I can show the connection between Weyman, who would be the uncle of William West,” Owsley said.

Read more at Discovery News

100 Bodies Found Stuffed into Ancient House

The remains of 97 human bodies have been found stuffed into a small 5,000-year-old house in a prehistoric village in northeast China, researchers report in two separate studies.

The bodies of juveniles, young adults and middle-age adults were packed together in the house — smaller than a modern-day squash court — before it burnt down. Anthropologists who studied the remains say a “prehistoric disaster,” possibly an epidemic of some sort, killed these people.

The site, whose modern-day name is “Hamin Mangha,” dates back to a time before writing was used in the area, when people lived in relatively small settlements, growing crops and hunting for food. The village contains the remains of pottery, grinding instruments, arrows and spearheads, providing information on their way of life.

“Hamin Mangha site is the largest and best-preserved prehistoric settlement site found to date in northeast China,” a team of archaeologists wrote in a translated report published in the most recent edition of the journal Chinese Archaeology (the original report appeared in Chinese in the journal Kaogu). In one field season, between April and November 2011, the researchers found the foundations of 29 houses, most of which are simple one-room structures containing a hearth and doorway.

The house with the bodies, dubbed “F40,” was just 210 square feet (about 20 square meters). “On the floor, numerous human skeletons are disorderly scattered,” the archaeologists wrote.

Photos taken by the archaeologists convey the prehistoric scene better than words do. “The skeletons in the northwest are relatively complete, while those in the east often only skulls, with limb bones scarcely remaining,” the archaeologists wrote. “But in the south, limb bones were discovered in a mess, forming two or three layers.”

At some point the structure burnt down. The fire likely caused wooden beams of the roof to collapse, leaving parts of skulls and limb bones not only charred but also deformed in some way, the archaeologists wrote.

The remains were never buried and were left behind for archaeologists to discover 5,000 years later.

What happened?

An anthropological team at Jilin University in China is studying the prehistoric remains, trying to determine what happened to these people. The team has published a second study, in Chinese, in the Jilin University Journal – Social Sciences edition, on their finds. (A brief English-language summary of their results is available on the American Association of Physical Anthropologists website.)

The Jilin team found that the people in that house died as the result of a “prehistoric disaster” that resulted in dead bodies being stuffed into the house.

The dead came in faster than they could be buried. “The human bone accumulation in F40 was formed because ancient humans put remains into the house successively and stacked centrally,” wrote team leaders Ya Wei Zhou and Hong Zhu in the study.

The team found that about half of the individuals were between 19 and 35 years of age. No remains of older adults were found.

The ages of the victims at Hamin Mangha are similar to those found in another prehistoric mass burial, which was previously unearthed in modern-day Miaozigou in northeast China, the researchers noted.

“This similarity may indicate that the cause of the Hamin Mangha site was similar to that of the Miaozigou sites. That is, they both possibly relate to an outbreak of an acute infectious disease,” wrote Zhou and Zhu.

Read more at Discovery News

560,000-Year-Old Tooth Found by French Teenager

AFP - A 16-year-old French volunteer archaeologist has found an adult tooth dating back around 560,000 years in southwestern France, in what researchers hailed as a "major discovery" Tuesday.

"A large adult tooth -- we can't say if it was from a male or female -- was found during excavations of soil we know to be between 550,000 and 580,000 years old, because we used different dating methods," paleoanthropologist Amelie Viallet told AFP.

"This is a major discovery because we have very few human fossils from this period in Europe," she said.

The tooth was found at one of the world's most important prehistoric sites in Tautavel, which has been excavated for about 50 years.

It is also the site of the discovery of fossils belonging to Tautavel Man, a species that lived an estimated 450,000 years ago.

Volunteer Camille, 16, was working with another young archaeologist when she found the tooth.

From Discovery News

Jul 27, 2015

Search Heats Up for What Wiped Out Ichthyosaurus

During the dinosaur age, ichthyosaurs — large marine reptiles that look like dolphins — flourished in prehistoric oceans, living in all kinds of watery environments near and far from shore. But as competition in these areas grew, ichthyosaurs lost both territory and species before gradually going extinct, a new study finds.

In fact, the ichthyosaur extinction has stumped scientists for years. Ichthyosaurs likely evolved from land reptiles that dove into the ocean about 248 million years ago, researchers said. After living along the coast for millions of years, they left for the open water. They disappeared about 90 million years ago, going extinct about 25 million years before the dinosaur-killing asteroid slammed into Earth.

So, if the asteroid didn't kill the ichthyosaurs, what did? To learn more, researchers looked at ichthyosaur fossils and determined what kinds of specialized environments, or niches, the animals likely inhabited.

"In most studies, the niche of the animal is predicted based on a single trait, usually the shape of the teeth," said lead researcher Daniel Dick, a doctoral student in paleontology at the Natural History Museum in Stuttgart, Germany. In the new study, the researchers looked at several traits, he said.

For instance, they analyzed the ichthyosaurs' body sizes and teeth shapes. They also determined each animal's feeding strategy, such as whether ichthyosaurs were ambush predators (less powerful swimmers) or pursuit predators (fast swimmers), Dick said.

After examining 45 ichthyosaur genuses, Dick and his colleague Erin Maxwell, a vertebrate paleontologist at the museum, used an analysis that grouped the ichthyosaurs into seven categories, called ecotypes.

For instance, the ichthyosauriform genus, Cartorhynchus, is so unique that it has its own ecotype. It was likely a small suction feeder and lived in shallow water, Dick told Live Science.

Another ecotype represents the majority of the genuses that lived during the Early to Middle Triassic period, he said. Animals of this ecotype were less than 6.5 feet (2 meters) long, and had robust and blunt teeth, suggesting they ate hard-shelled prey, such as coral and shelled mollusks, Dick said. They didn't have elongated bodies, so they probably didn't live in the open water, where they would have needed to swim far distances, he added.

Two genuses — Eurhinosaurus and Excalibosaurus — owe their unique ecotype to their swordfishlike jaws, which indicate they used a slashing method to demolish prey, Dick said. Their long bodies also indicate they lived in the open water, far from shore, he said.

Not all seven ecotypes existed at once, although five existed simultaneously during the Early Jurassic period, when ichthyosaurs experienced a boom in diversity.

By the Middle Jurassic, the number of ichthyosaur ecotypes decreased. Specialized feeders, such as the swordfishlike Eurhinosaurus, and apex predators, including Temnodontosaurus, went extinct, leaving only two ecotypes, both of which lived in the open water.

These last two ecotypes included ichthyosaur genuses with large bodies and robust teeth for crushing bony fish or hard cephalopods, such as ammonites. The other ecotype was more dolphinlike; it had small teeth and likely ate soft prey, such as squid (also cephalopods), Dick said.

Ichthyosaurs eventually met their end during the Cenomanian-Turonian extinction event, in which spinosaurs (carnivorous swimming dinosaurs), plesiosaurs (long-necked marine reptiles) and roughly one-third of marine invertebrates (animals without a backbone) also went extinct, Dick said.

With only two ecotypes of ichthyosaurs left, they would have been easily wiped out, Dick said.

"It's a slow ecological war of attrition, where they become more and more stranded on a single niche, and then the entire is depending on that niche remaining sustainable," he said. "And if that became unsustainable, then the entire group would become extinct."

It's unclear why ichthyosaurs lost their earlier niches, but they were likely "replaced, outcompeted by other species that adapted better," Dick said. For instance, plesiosaurs took over many of the near-shore niches, he said.

The study sheds light on ichthyosaurs' evolution and extinction, said Neil Kelley, a postdoctoral research fellow of paleobiology at the National Museum of Natural History in Washington, D.C., who was not involved in the new research.

Read more at Discovery News

Ancient Volcano Tattooed the Earth with Giant Rings

Concentric circles of rocky hills and valleys in South Africa tell the story of a billion-year-old collapsed volcano in newly released photos from NASA.

The circular Pilanesberg caldera is located in the South African province known as North West, in Pilanesberg National Park. The caldera, or cauldron-shaped crater, features different rings of rock that make up a near perfect circle, with structures that rise about 330 to 1,640 feet (100 to 500 meters) above the surrounding landscape. The tallest point, Matlhorwe Peak, soars 5,118 feet (1,560 m) above sea level.

Several streams typically flow through the valleys of these structures, but the Earth-watching Landsat 8 satellite captured the landscape when it was dry, according to NASA Earth Observatory. Man-made dams trap water for the many animals in the region, and Mankwe Lake, the largest body of water in the park, is located in the lowlands east of the center of the rings.

The Pilanesberg’s story begins about 1.3 billion years ago, when only very simple organisms, like algae, roamed the Earth and volcanoes frequently spewed magma. This molten rock is created in a large pool (called a “hot spot”) just below the Earth’s crust. When there’s enough of the substance, the pressure rises and magma eventually forces its way through the crust, bursting in a shower of fiery, boiling rock, ash and gas.

After the eruption, the ruptured crust collapses into the magma chamber, similar to how skin subsides after a pimple is popped. Magma remaining underneath the crust is propelled upward, just as pus seeps out from under the skin after a pimple bursts, and floods the landscape as lava. The lava then solidifies into volcanic rocks, which can look dark and glassy (obsidian) or grey and spongy (basalt), and can display other characteristics.

Magma that does not make it to the surface as lava cools and hardens, clogging the cracks inside the Earth. These solidified magma formations are called dikes, and in Pilanesberg, many of the dikes are circular because of the circular cracks. As such, these formations are known as ring dikes, NASA officials said.

This cycle occurred many times during this volcano’s active period of about 1 million years, according to NASA. Each time new cracks opened, melted magma erupted and formed different rocks. Tectonic activity, or the movement of continental plates, eventually drifted the volcano away from its hot spot, so Pilanesberg is now dormant, according to NASA Earth Observatory.

In the millions of years since Pilanesberg stopped erupting, erosion from rain, wind and other natural processes removed the volcanic rocks and exposed the inside of the original volcano and its erosion-resistant ring dikes, which are the strangely circular features seen today.

Read more at Discovery News

Isolated Amazon Tribe To Be Contacted by Peru Govt

The Peruvian government plans to make its first contact with the Mashco Piro, an isolated tribe that live in the Amazon rainforest.

Reaching out to “uncontacted” tribes is controversial, particularly because isolated tribes lack immunity to common diseases, which can quickly turn deadly. But officials say they need to contact the Mashco Piro because the group has recently been emerging from the forest, and have had contact with villagers, tourists and missionaries.

In September 2014, for example, the advocacy group Survival International reported that Adventist missionaries had left food and clothes for the tribe near the border of Manu National Park. Gestures like this have spread diseases to uncontacted people in the past, causing epidemics.

Tour companies also advertise “human safaris,” promising glimpses of Mashco Piro tribespeople along riverbanks.

As a result of these largely unplanned, uncontrolled contacts, some anthropologists argue for deliberate contact with isolated peoples. (Most uncontacted tribes do have limited interactions with their neighbors and are aware of the outside world, but choose to maintain an isolated and nomadic lifestyle in the forest.)

“Unless protection efforts against external threats and accidental encounters are drastically increased, the chances that these tribes will survive are slim,” anthropologists Robert Walker of the University of Missouri and Kim Hill of Arizona State University wrote in an editorial in the journal Science in June.

Controlled contact — with medical treatment available for inevitable disease transmission — is safer, Hill and Walker argued.

“A well-designed contact can be quite safe, compared to the disastrous outcomes from accidental contacts,” they wrote. “But safe contact requires a qualified team of cultural translators and health care professionals that is committed to staying on site for more than a year.”

Organizations such as Survival International strongly oppose contact, arguing instead for strict protections of native land. Given activities such as illegal logging and drug trafficking, however, those protections can be hard to enforce.

The Mashco Piro have been making their own forms of contact, according to Reuters. Members of the tribe attacked a settlement of the Machiguenga tribe in May 2015, killing one man. Another clash in 2011 between locals and the tribe reportedly left one dead and a park ranger injured. Two groups of uncontacted Peruvians approached Brazilian authorities in July and August 2014, saying they had been attacked by non-Indians, possibly drug runners or illegal loggers.

Read more at Discovery News

These Crazy-Dense Galaxies are Packed With Stars

The most dense galaxies known to exist in our universe have been discovered by 2 undergraduate students while looking through years of archival data. The discovery of the galactic pair makes them the most dense of a new category of galaxy, called ultracompact dwarfs (UCDs), discovered to date.

To say the galaxies are “dense” is an understatement. The first galaxy, called M59-UCD3, is around 200 times smaller than our galaxy, but has a density 10,000 times the density of stars surrounding our solar system. The second galaxy found, called M85-HCC1, is even more dense; around a million times that of the solar system’s neighborhood.

For an observer standing on a hypothetical planet in the core of one of these UCDs, the “night” sky would dense with bright stars (as depicted in the artist’s impression above).

Although notable, the pair of UCDs weren’t easy to spot and the first UCD was uncovered by pure luck.

“Ultracompact stellar systems like these are easy to find once you know what to look for,” said Richard Vo, undergraduate student at San José State University. “However, they were overlooked for decades because no one imagined such objects existed: they were hiding in plain sight.”

“When we discovered one UCD serendipitously, we realized there must be others, and we set out to find them.”

Vo and fellow student Michael Sandoval scoured data from the Sloan Digital Sky Survey, the Subaru Telescope, Hubble Space Telescope, the Goodman Spectrograph on the Southern Astrophysical Research Telescope (SOAR), revealing the 2 UCDs orbiting larger, massive galaxies. Their close proximity to larger galaxies may reveal how these UCDs came to be so dense.

“One of the best clues is that some UCDs host overweight supermassive black holes, sadi Sandoval. “This suggests that UCDs were originally much bigger galaxies with normal supermassive black holes, whose fluffy outer parts were stripped away, leaving their dense centers behind. This is plausible because the known UCDs are found near massive galaxies that could have done the stripping.”

An additional clue that this may be the case is that spectroscopic analysis has revealed an abundance of heavy elements such as iron in the UCDs — a characteristic of much larger galaxies that are efficient heavy element factories. Their findings have been published in a Astrophysical Journal Letters paper.

The availability of archival data and dedication by Sandoval and Vo, who undertook this search in their spare time, helped them find these UCDs, despite not having access to astronomical facilities.

Read more at Discovery News

Jul 26, 2015

Innovative algorithm is helping scientists decipher how drugs work inside the body

Researchers at Columbia University Medical Center (CUMC) have developed a computer algorithm that is helping scientists see how drugs produce pharmacological effects inside the body. The study, published in the journal Cell, could help researchers create drugs that are more efficient and less prone to side effects, suggest ways to regulate a drug's activity, and identify novel therapeutic uses for new and existing compounds.

"For the first time we can perform a genome-wide search to identify the entire set of proteins that play a role in a drug's activity," says study co-author Dr. Andrea Califano, the Clyde and Helen Wu Professor of Chemical Systems Biology and chair of the department of Systems Biology at CUMC.

Scientists design drugs to pinpoint molecular targets in the cell. However, when a drug enters the human body, it becomes part of an incredibly complex system, and can interact with other molecules in ways that are hard to predict. This unanticipated cross-talk causes side effects and stops many promising drug candidates from being used in clinical care. Unfortunately, current experimental methods don't allow scientists to identify the full repertoire of proteins that are affected by a drug.

Members of Dr. Califano's lab have devised a new approach called DeMAND.

(Detecting Mechanism of Action by Network Dysregulation) to characterize a drug's effects more precisely. The method involves creating a computational model of the network of protein interactions that occur in a diseased cell. Experiments are then performed to track gene expression changes in diseased cells as they are exposed to a drug of interest. The DeMAND algorithm combines data from the model with data from the experiments to identify the complement of proteins most affected by the drug.

DeMAND improves on more labor intensive and less efficient methods, which are only capable of identifying targets to which a compound binds most strongly. This provides a more comprehensive picture, because DeMAND identifies many molecules that are affected in addition to the drug's direct target.

So far, DeMAND's predictions are proving to be accurate when tested with follow-up experiments. The researchers report that when they exposed human diffuse B-cell lymphoma cells to a panel of drugs, the algorithm identified 70% of previously documented targets. "The accuracy of the method has been the most surprising result," says Dr. Califano.

The algorithm makes it possible to identify a variety of compounds that cause similar pharmacological outcomes. Using DeMAND, the researchers showed that a similar subset of proteins is affected by the unrelated drugs sulfasalazine and altretamine. Altretamine is currently used to treat ovarian cancer, but these results suggest that, like sulfasalazine, it could be used for bowel inflammation or rheumatoid arthritis too.

Read more at Science Daily

Four-legged snake fossil found

An "absolutely exquisite" fossil of a snake that had four legs has been discovered by a team of scientists and may help show how snakes made the transition from lizards to serpents.

It is the first known fossil of a four-legged snake, and the team -- led by Dr Dave Martill from the University of Portsmouth -- say that this discovery could help scientists to understand how snakes lost their legs.

The findings were published in the journal Science.

Dr Martill said: "It is generally accepted that snakes evolved from lizards at some point in the distant past. What scientists don't know yet is when they evolved, why they evolved, and what type of lizard they evolved from. This fossil answers some very important questions, for example it now seems clear to us that snakes evolved from burrowing lizards, not from marine lizards."

The fossil, from Brazil, dates from the Cretaceous period and is 110 million years old, making it the oldest definitive snake.

Dr Martill discovered the fossil as part of a routine field trip with students to Museum Solnhofen, Germany, a museum that is well-known for its prestige with regard to fossils.

Dr Martill said: "The fossil was part of a larger exhibition of fossils from the Cretaceous period. It was clear that no-one had appreciated its importance, but when I saw it I knew it was an incredibly significant specimen."

Dr Martill worked with expert German palaeontologist Helmut Tischlinger, who prepared and photographed the specimen, and Dr Nick Longrich from the University of Bath's Milner Centre for Evolution, who studied the evolutionary relationships of the snake.

Dr Longrich, who had previously worked on snake origins, became intrigued when Martill told him the story over a pint at the local pub in Bath.

He said: "A four-legged snake seemed fantastic and as an evolutionary biologist, just too good to be true, it was especially interesting that it was put on display in a museum where anyone could see it."

He said he was initially sceptical, but when Dr Martill showed him Tischlinger's photographs, he knew immediately that it was a fossil snake.

The snake, named Tetrapodophis amplectus by the team, is a juvenile and very small, measuring just 20cm from head to toe, although it may have grown much larger. The head is the size of an adult fingernail, and the smallest tail bone is only a quarter of a millimetre long. But the most remarkable thing about it is the presence of two sets of legs, or a pair of hands and a pair of feet.

The front legs are very small, about 1cm long, but have little elbows and wrists and hands that are just 5mm in length. The back legs are slightly longer and the feet are larger than the hands and could have been used to grasp its prey.

Dr Longrich said: "It is a perfect little snake, except it has these little arms and legs, and they have these strange long fingers and toes.

"The hands and feet are very specialised for grasping. So when snakes stopped walking and started slithering, the legs didn't just become useless little vestiges -- they started using them for something else. We're not entirely sure what that would be, but they may have been used for grasping prey, or perhaps mates."

Interestingly, the fossilised snake also has the remains of its last meal in its guts, including some fragments of bone. The prey was probably a salamander, showing that snakes were carnivorous much earlier in evolutionary history than previously believed.

Helmut Tischlinger said: "The preservation of the little snake is absolutely exquisite. The skeleton is fully articulated. Details of the bones are clearly visible and impressions of soft tissues such as scales and the trachea are preserved."

Tetraphodophis has been categorised as a snake, rather than a lizard, by the team due to a number of features:

· The skeleton has a lengthened body, not a long tail.

· The tooth implantation, the direction of the teeth, and the pattern of the teeth and the bones of the lower jaw are all snake-like.

· The fossil displays hints of a single row of belly scales, a sure fire way to differentiate a snake from a lizard.

Read more at Science Daily