Learning makes animals intelligent

An orangutan builds an umbrella against the rain. Efficient and intelligent behaviour that can be explained by new research from Stockholm University and Brooklyn College.

The fact that animals can use tools, have self-control and certain expectations of life can be explained with the help of a new learning model for animal behaviour. Researchers at Stockholm University and Brooklyn College have combined knowledge from the fields of artificial intelligence, ethology and the psychology of learning to solve several problems concerning the behaviour and intelligence of animals.

Animals are often very effective; an oystercatcher opens mussels quickly, a baboon takes every opportunity to steal food from tourists or a rat navigates with ease between the bins in a park. Previously these behaviours have been considered to be inherited instincts, even though it is well known that animals have great learning abilities. Researchers from Stockholm University and Brooklyn College have now created an associative learning model that explains how effective behaviours can arise. This means that an animal does not only learn that the last step of a behaviour chain, the one that is rewarding, is valuable. An animal can learn that all steps towards the reward are valuable.

"Our learning model may also explain how advanced behaviours are created at an individual level. Behaviours like self-control, chimpanzee tool use as well as other phenomena like animals having certain expectations of live," says Magnus Enquist, professor of ethology at Stockholm University. "Similar models are used in the field of artificial intelligence, but they have been ignored in animal studies."

Since the 1970s it has been known that animals weigh the cost of a certain behaviour against the profit and that they, to a high degree, make optimal decisions, which is assumed to be genetically determined. The research group's new model deals not only with learning, it also takes into account the idea that what animals are able to learn can be genetically regulated.

"Young animals are often a bit clumsy, while adult animals are extremely skilled. A small cub does not even consider a vole as food, while an adult fox is an expert vole catcher," says Johan Lind associate professor of ethology at Stockholm University. "Our model shows how genetic regulation of learning can influence the development of species-specific behaviour and intelligence since evolution can affect curiosity and the speed of learning among other things."

The researchers' new model could also explain counterproductive behaviour in artificial environments.

"Many learning models can explain optimal behaviour, but to explain counterproductive behaviour an understanding of the mechanisms of the behaviour is needed. Using our model, we manage to explain why animals get stuck in suboptimal behaviour. Like a hamster running in its hamster wheel despite having food next to it. Our model has captured fundamental aspects of learning," says Stefano Ghirlanda, professor of psychology at Brooklyn College in New York.

Read more at Science Daily

Some Viking Left His Toolbox at a Danish Fortress 1,000 Years Ago

A Viking toolbox found in Denmark has been opened for the first time in 1,000 years, revealing an extraordinary set of iron hand tools that may have been used to make Viking ships and houses, according to archaeologists.

The tools were found this summer at a mysterious, ring-shaped fortress at Borgring, on the island of Zealand. The famed 10th-century Danish king Harald Bluetooth is thought to have ordered the construction of the fortress.

So far, archaeologists have found at least 14 iron tools inside a single deposit of earth excavated from a gatehouse building of the fortress. The researchers said only traces remain of the wooden chest that once held the tools.

Iron was valuable in Viking-age Denmark, and the researchers think the tools once belonged to a craftsman who occupied a workroom in the gatehouse until it collapsed in the late 10th century.

The archaeologists are still studying the heavily rusted objects, but they've already identified several sophisticated hand tools and other metal items, including a set of "spoon drills" that were used to make holes in timber; what looks like a pair of tweezers or small pliers; a "clink nail" used to fasten wooden planks together; four carefully crafted chain links attached to an iron ring; and a drawplate to make metal wires that may have been used in jewelry.

Archaeologist Nanna Holm, a curator at the Danish Castle Center in Vordingborg who is leading the excavations of the ringed-shaped fort at Borgring, said this is the first time an entire set of tools has been discovered in a Viking workplace.

"This is not an ordinary find," Holm told Live Science. "Not many tools are found in Scandinavia, but the others found before this have all been left for the gods, by being put down in a swamp."

The newfound tools are special because they were found where the craftsman would have been working, she said. "That's why it's so exciting for us to see what's inside, because we can see what one man has used at this specific site," Holm added.

Viking iron

The cache of iron tools was first located by amateur archaeologists using a metal detector near the eastern gate of the buried fortress at Borgring.

That discovery inspired Holm's archaeological team in August to excavate the eastern gatehouse, where they removed the deposit of earth containing all the tools in one piece — a delicate process that took two days.

The next step was to transport the lump of earth, rust and iron to a local hospital, where it was scanned with computed tomography (CT) equipment usually used by doctors to examine the internal organs of their patients.

The CT scans revealed the precise arrangement of at least 14 iron tools, which have since been excavated from the toolbox deposit for individual X-ray studies and preservation before they are put on display in an exhibition next year, Holm said.

All of the tools are heavily corroded, but much of the original iron remains, and even more tools may be hidden in the rust, according to the researchers. "There are a minimum of 14 tools, but I think there are 16 now, from the new X-rays that we've already done," Holm said.

The contents of the toolbox provide a rare glimpse of working life in the late Viking age, she said.

"They can be used for different crafts," Holm said. "We have some spoon drills for making holes in wood, which could be used for building ships or for building houses."

The iron drawplate has a series of small holes of different sizes that were used to make wires from softer metals, the researchers said. "You pulled the metal through each of the holes to make it smaller and smaller, and thinner and thinner," she explained.

The toolbox is an important early find for the archaeologists, who will conduct further excavations at Borgring each summer for the next three years, Holm said. [Fierce Fighters: 7 Secrets of Viking Culture]

The remains of houses and human graves have been found at other Viking ring forts, but the toolbox is the first direct evidence of human habitation at Borgring itself, she added.

"So far, we haven't found any houses, but we now have proof that there were people here — so hopefully, next year, we will find their houses," Holm said.

Read more at Discovery News

Predation on pollinating insects shaped the evolution of the orchid mantis

A typical male orchid mantis, Hymenopus coronatus, from Sarawak, Borneo showing brown and white coloration with transparent wings.

A team of scientists at The Cleveland Museum of Natural History, Australia, and Germany discovered that the orchid mantis looks like a flower due to the exploitation of pollinating insects as prey by its praying mantis ancestors.

By studying the evolutionary relationships of the orchid mantis and its distant relatives, the team discovered that females in the orchid mantis lineage increased in size and changed color over their evolutionary history to gain advantage over large pollinating insects, such as bees, as well as the ability to attract them for predation. However, the morphologically dissimilar males are small and camouflaged, enabling them to live a life of predator avoidance and mate finding. The team found that this difference in males and females, termed sexual dimorphism, was likely the result of female predatory success that favored larger and more conspicuously colored individuals. This result challenges the traditional explanation for sexual dimorphism in arthropods as an increase in female egg production and suggests female predation strategy led to the differing male and female ecologies in the orchid mantises.

The research was published online in the journal Scientific Reports.

Lead author Dr. Gavin Svenson of the Cleveland Museum of Natural History and co-authors used their evolutionary reconstruction of the group to demonstrate that a size increase in floral associated mantises provided access to more prey options, which set the stage for the evolution of floral simulation through size, shape, and color modifications that helped attract insect pollinators as prey. Thanks to a body of ecological research on the orchid mantis previously conducted by co-author Dr. James O'Hanlon of Macquarie University in Australia, it was known that females masquerade as flowers (floral simulation) to attract pollinating insects to eat, but that they do not sit on flowers themselves. This knowledge helped the team decipher the likely evolutionary scenario that gave rise to floral simulation in the orchid mantises and provided the opportunity to correct the long-held misunderstanding that orchid mantises sit on orchids, which their namesake incorrectly suggests.

"This study is a demonstration of how basic systematics research can inform our understanding of evolution by establishing patterns not previously seen," said co-author Henrique Rodrigues.

"Bringing together ecological research with an evolutionary analysis enabled us to explain how such a remarkable, flower masquerading lineage of praying mantis could evolve," said co-author Sydney Brannoch. Co-authors Rodrigues and Brannoch are both Ph.D. candidates at Case Western Reserve University and are based at the Cleveland Museum of Natural History in Svenson's laboratory.

The research project, under the direction of Svenson, was primarily focused on the systematics and taxonomy of a broader lineage of praying mantises, which included the orchid mantises. Acting on a suggestion made by co-author Dr. Frank Wieland of the Palatinate Museum of Natural History in Germany, the team took notice of a small group of extremely large and colorful mantises that grouped together in the evolutionary analysis. Although these relationships were never before outlined, they suggested a clear pattern of extreme sexual dimorphism in the orchid mantis lineage.

Read more at Science Daily

Cassini Probe Begins Tango With Saturn's Rings

In less than 10 months, NASA's Cassini spacecraft will swan dive into Saturn, ending a 20-year trip around the ringed beauty and its entourage of moons. But before it goes, scientists plan some parting gifts.

This week, Cassini made its penultimate swing past Titan, the largest of Saturn's 62 named moons, so it could be gravitationally elbowed into a new orbit that is more perpendicular to Saturn's equator and rings.

The new path shoots Cassini through the edge of the outer ring, giving scientists unprecedented opportunities to sample ring particles, sniff surrounding gases, blast the rings with radio waves and snap some stupendous pictures.

The first pass by the F ring will occur on Sunday, with 19 more ring-grazing orbits to follow at a pace of one a week.

For its closing act, Cassini will make a final swoop by Titan and go nearly polar around the planet so it can swoop between Saturn and the inner ring.

The journey ends on Sept. 15, 2017, when Cassini plunges into Saturn's thick atmosphere to prevent a most unlikely, but not impossible scenario: contaminating any potentially habitable moons with hitchhiking Earth microbes tenacious enough to have survived 20 years in the radioactive environment of space.

NASA plans to end the mission before Cassini runs out of fuel for its steering thrusters. But for the next 9.5 months, that's the furthest thing from scientists' minds.

From Discovery News

Hubble Spies a Strange Old Dusty Galaxy

The Hubble Space Telescope is an expert at imaging distant galaxies, bringing mysterious galactic features into the light. In the case of one particular elliptical galaxy, around 150 million light-years distant, Hubble has revealed a conundrum and a possible mechanism behind why some galaxies look so old.

NGC 4696 possesses huge clouds of dust and gas, spiraling through the galaxy's structure to its core, but this material isn't being used for star formation. In fact, NGC 4696 is populated with ancient stars and researchers hope to use this stunning example to help us understand why there are so many massive galaxies like it.

NGC 4696 occupies the huge Centaurus galaxy cluster which consists of hundreds of galaxies bound together by gravity. Though the cluster is vast, NGC 4696 stands out from the crowd as it is so bright. It's so bright, in fact, that it has the moniker "Brightest Cluster Galaxy." It is known to have an active core occupied by a supermassive black hole that appears to be consuming these beautiful spiraling tendrils.

These dusty structures have a width of around 200 light-years and they all knit together, creating a conveyor belt of material flooding into the black hole. The black hole then heats the material that spirals in, blasting superheated gases away from the core that sculpt the infalling dust into the shape as seen so clearly by Hubble.

It's well known that central supermassive black holes, which are known to live in the cores of the vast majority of galaxies, have a significant role in regulating the amount of star formation.

In the case of NGC 4696, it appears the galaxy's core is physically shaping the structure of these dusty tendrils and an international team of astronomers, headed by researchers at the University of Cambridge, suspect that powerful magnetic fields are threading through the galaxy's structure, corralling the dust in such a way that its funneled into the black hole. But the black hole is the engine behind it all, erupting with hug amounts of energy and actively stifling star formation.

From Discovery News

Ancient Wind God Temple Found Under Mexico City Supermarket

Archaeologists excavating the site of a demolished supermarket in Mexico City have unearthed a circular temple built more than 650 years ago for an Aztec deity.

The platform, about 36 feet in diameter and four feet tall, was part of the sacred area of the city-state Tlatelolco and was likely dedicated to the god of wind Ehecatl-Quetzalcoatl. It now stands just yards away from the site of the Tlatelolco 1968 massacre, where Mexican soldiers killed protesting students.

The 10-foot deep excavation began two years ago when an old supermarket at the site was demolished. The work first revealed the upper part of the structure, along with pottery shards and 20 burials, which included adults, children and animals.

In March of this year, archaeologists led by Edwina Villegas Gómez, director of the archaeological area of Tlatelolco, brought to light the circular platform with its original white stucco still intact.

At the eastern entrance of the temple, they found a small, stone coffin-like box. Offerings inside included the remains of a newborn child with no signs of trauma, cactus thorns, bird bones, incense burners and pieces of obsidian and pottery depicting monkeys and duck bills.

In early October, the skull of an adult male was also found. Next to it, there was a ring which was worn by the individual.

According to INAH, Mexico's National Institute of Anthropology and History, burials around the temple contained eight complete skeletons (six infants, an adult female and an adult male), as well as other incomplete human remains.

The finding offers another example on how the Mexica-Tlatelolca people worshiped their deities, and adds a new piece to the great puzzle of Tlatelolco's ceremonial center, which is now mostly covered by urban developments.

Preservationists plan to build a protective wall around the site, including a large viewing window and ramp to make it visible to the public.

From Discovery News

A Mysterious Snake Disease Is Spreading as the Planet Warms

When Matthew Allender of the University of Illinois at Urbana-Champaign first saw snake fungal disease victims in 2010, he knew that he was witnessing a devastating illness. He told Seeker, "You could hardly even tell that they were snakes, since some were so disfigured."

The disease, caused by a fungus called Ophidiomyces ophiodiicola, can result in thickened skin, ulcers, blisters, emaciation and, in the majority of cases, death. It has infected over 20 species of wild snakes and has spread to snakes in at least 20 U.S. states, parts of Canada, and to captive snakes in many countries. Scientists say the spread of the disease is an ominous symptom of climate change.

There is some good news to report—the very recent discovery of a promising treatment—at least for captive snakes.

The treatment, which was announced at an American Association of Zoo Veterinarians meeting and will be outlined in a future paper, centers on a nebulizer. People with asthma use similar devices, which are readily available at everywhere from discount shops to "big-box" stores.

Here's how it works: A sick snake is placed in a fish tank-resembling chamber before an anti-fungal agent is pumped in via the nebulizer. The medicated "steam falls on the skin and the snake inhales it," Allender said.

While the process seems to clear up visible signs of the disease, treating wild snakes isn't terribly practical. The elusive nature of snakes, not to mention the need to capture and then diagnose wild-living victims of the disease, complicate implementing the cure. It holds promise for treating pet snakes and others in captivity, however, such as snakes at zoos.

Still, it remains unknown if snakes could still internally harbor the fungus and later pass it on to others of their own kind. (There are no known cases of it spreading to humans.)

Ideally the disease could be wiped out in the wild, but many mysteries still surround it, including how it might be connected to other fungal diseases, including those affecting humans.

"Over 80 percent of emerging diseases are fungal infections," Allender said. "A big question now is if they are all somehow linked."

He and his colleagues note that there are parallels between snake fungal disease and white-nose syndrome, an often-deadly infection affecting bats that is caused by the Pseudogymnoascus destructans fungus. Both pathogens seem to have spread quickly in recent years, and both can survive on most carbon and nitrogen sources found in soils, making them prevalent in the environment.

While it's largely believed that the white-nose pathogen was introduced into North America in more recent years, the presence of O. ophiodiicola in America has been known for some time. It was considered to be a relatively benign organism before one or more triggers likely led to it becoming a snake killer.

Northern water snake with fungal infection-caused deformity.

In a study published earlier this year, Allender and his colleagues evaluated how common disinfectants work against the fungus. Alcohol, bleach and certain other over-the-counter cleaners did a good job, but intriguingly, a common agricultural fungicide did not. He said further studies are needed to determine what role, if any, the fungicide's active ingredient—propiconazole—could play in the spread of snake fungal disease.

Jeffrey Lorch, a microbiologist with the U.S. Geological Survey National Wildlife Health Center, told Seeker that he does not believe there is a connection between these particular agricultural fungicides and the emergence of the disease "unless the fungicides are causing the immune system of snakes not to function properly."

Although the jury is still out on this matter, both he and Allender say climate change is contributing to the prevalence and severity of snake fungal disease.

Read more at Discovery News

Astronomers watch star clusters spewing out dust

In the galaxy II Zw 40, dust (shown in yellow) is strongly associated with clusters of stars (shown in orange). UCLA researchers have used new observations of this galaxy to confirm that these stars are creating enormous amounts of dust.

Galaxies are often thought of as sparkling with stars, but they also contain gas and dust. Now, a team led by UCLA astronomers has used new data to show that stars are responsible for producing dust on galactic scales, a finding consistent with long-standing theory. Dust is important because it is a key component of rocky planets such as Earth.

This research is published online today in Astrophysical Journal Letters.

Jean Turner, a UCLA professor in the department of astronomy and physics, her graduate student S. Michelle Consiglio, and two other collaborators observed a galaxy roughly 33 million light-years away. The researchers focused on this galaxy, called "II Zw 40," because it is vigorously forming stars and therefore useful for testing theories of star formation. "This galaxy has one of the largest star-forming regions in the local universe," Turner said.

The researchers, led by Consiglio, obtained images of II Zw 40 using the Atacama Large Millimeter/submillimeter Array telescope. This telescope, located in Chile's Atacama desert, is composed of an array of 66 individual telescopes that function as a single large observatory. In 2011, Turner took a three-month sabbatical from UCLA to help prepare the Atacama Array to be used by the astronomical community. "I helped with reducing data and served as astronomer on duty," she said.

The telescope is sensitive to light in the millimeter and submillimeter part of the electromagnetic spectrum, just slightly shorter than microwaves. Capturing this kind of light requires a telescope at high altitudes -- this one is built on a plateau at 16,400 feet -- because "the Earth's atmosphere is beginning to absorb very strongly at those wavelengths," Turner said. "All ALMA scientists work at a lower elevation because you can't think well at that altitude," she added.

Consiglio and her team observed the central region of II Zw 40, a part of the galaxy with two young clusters of stars, each containing roughly a million stars. By imaging II Zw 40's star clusters at different wavelengths, they constructed a map that traced the dust in the galaxy. Astronomical dust -- made mostly of carbon, silicon and oxygen -- is prevalent in the universe. "If you look at the Milky Way in the sky, it looks kind of patchy and splotchy. That's due to dust blocking the light," Turner said.

The researchers tested whether the location of the galaxy's dust was consistent with the location of the galaxy's star clusters. They found that it was: Consiglio and her team showed that II Zw 40's dust was concentrated within roughly 320 light-years of the star clusters. "The dust is all focused near the double cluster," Turner said. This observation supported their hypothesis that stars are responsible for producing dust. "The double cluster is a 'soot factory' polluting its local environment," Consiglio said.

Scientists have long theorized that stars produce dust by expelling the elements fused deep within their interiors, enriching their host galaxies in elements heavier than hydrogen and helium. However, astronomical data have thus far not backed up that claim. "People have looked for this large-scale enrichment of galaxies, but they haven't seen it before," Turner said. "We're seeing galaxy-scale enrichment and we see clearly where it is coming from."

The researchers propose that the dust enrichment is so obvious in II Zw 40's star clusters because they contain large numbers of very young, massive stars, which are the producers of dust. "The evolutionary time scales of these stars are short enough that you see the dust before it has a chance to get dispersed very far from its source," Turner said. "We're looking at the best place to see dust enrichment, in large star clusters," Consiglio added.

Read more at Science Daily

'Bickering' flies make evolutionary point

Julia Saltz, an evolutionary biologist at Rice University, placed genetically distinct variants of fruit flies in various and even uncomfortable situations to observe their behavior under stress and how it altered the behavior of interacting individuals when the "stressed" fly was moved to a new group.

When a male fruit fly gets aggressive, he rears up on his back four legs and batters his foe with his front pair. Neither fly seems particularly damaged by the encounter, but their subsequent actions are telling about the ways of social evolution, according to Rice University evolutionary biologist Julia Saltz.

Saltz went to the fruit fly fights every day for months to find out how the creatures' genotypes -- the genetic code that determines what they are -- affect their phenotypes -- the characteristics they present to their fellow flies.

In doing so, she bolstered the longstanding hypothesis in psychology that individuals are not merely subject to their social environments, but choose and create them through their interactions.

By placing genetically distinct variants of flies in various and sometimes uncomfortable situations, Saltz observed their behavior under stress and how stress altered the behavior of interacting individuals -- a process called social-environment construction -- when the "stressed" fly was moved to a new group for further observation.

"The main takeaway is that individuals' behaviors affect their social environments," she said. "In other words, when you pick your friends, it matters to you and it affects both what happens in the group and your behavior at a later time."

The study appears in the Nature journal Heredity.

Saltz, an assistant professor of biosciences, said few have undertaken direct studies of social-environment construction because of the difficulty involved. "You can't do it with people," she said, noting that it would be "unwise" to send someone into a room of subjects and have that person punch another.

But fruit flies are a worthy substitute, as both their genetic traits and environments can be manipulated easily, Saltz said.

Saltz, sole author of the paper, observed focal males -- her primary subjects -- either alone or with small groups of 2 to 8 fruit flies over two days in each experiment. (They totaled 1,300 flies over many months.) She placed genetically identical pairs in either their preferred or nonpreferred environments -- either large or small groups -- and measured their aggressive behaviors. She noted different genotypes of fly have different group-size preferences, allowing for variation among the experiments.

In the first stage of the study, she determined the preferences of focal males by genotype for group size. In the second stage, over hundreds of experiments, she put individual focal males into various-sized groups of "stimulus" flies.

"For day one, I put a 'genotype one' focal male with a group of flies, and a 'genotype two' with a replica group with the same sex ratio, number and genotype, reared under standard lab conditions," she said. "That way, I knew the social environment was the same for both focal males. If there was something different about how the groups behaved, it had to be due to the genotype of that one extra male.

"Arguably, the focal male would influence the behavior of other individuals in the group, which is what we saw," Saltz said.

She said males in their preferred groups were attacked more frequently than those in nonpreferred groups. "We don't totally know why that is, but we can say for sure the combination of that male's genotype and its preference caused the other males to act more aggressively toward it."

On day two, Saltz took the focal males -- dabbed with yellow paint to identify them -- from their initial groups and put each with a single "naïve" male in a petri dish "arena" and found the previous day's experience made them less aggressive.

That may show what Saltz called the "loser" effect, in which males who lose an initial encounter are less aggressive in subsequent encounters. "That seems to be true here, except that there's no good definition of losing," she said. "That's why I like to think of it as being attacked more often."

Saltz noted the flies display other types of aggression, and they may also pass chemical signals that are relevant in social environments. But lunging attacks were easiest to measure.

"It's an open question of how damaging aggression is to flies, but they seem totally fine after, so it's not like they can kill another male and then get all the food," she said. "There are subcomponents of aggression that are slightly ambiguous, but for this study I measured lunging, which doesn't look like any other behavior.

"The male actually rears up. The front two legs and part of its body go up and it slams its legs onto another male. It's not ambiguous, and a male can only lunge at one other male at a time, so you know exactly who was being aggressive and who was the recipient."

Read more at Science Daily

The coldest decade of the millennium?

One of the historical documents analysed by the team was a Bernese chronicle which contains the record 'Von einem grossen Sterbot zu Bernn' 1439 (About a great mortality in Bern 1439), Diebold Schilling, Amtliche Berner Chronik (1478-1483), vol. 2, Bern, Burgerbibliothek, Mss.h.h.I.2, p. 6.

While searching through historical archives to find out more about the 15th-century climate of what is now Belgium, northern France, Luxembourg, and the Netherlands, Chantal Camenisch noticed something odd. "I realised that there was something extraordinary going on regarding the climate during the 1430s," says the historian from the University of Bern in Switzerland.

Compared with other decades of the last millennium, many of the 1430s' winters and some springs were extremely cold in the Low Countries, as well as in other parts of Europe. In the winter of 1432-33, people in Scotland had to use fire to melt wine in bottles before drinking it. In central Europe, many rivers and lakes froze over. In the usually mild regions of southern France, northern and central Italy, some winters lasted until April, often with late frosts. This affected food production and food prices in many parts of Europe. "For the people, it meant that they were suffering from hunger, they were sick and many of them died," says Camenisch.

She joined forces with Kathrin Keller, a climate modeller at the Oeschger Centre for Climate Change Research in Bern, and other researchers, to find out more about the 1430s climate and how it impacted societies in northwestern and central Europe. Their results are published in Climate of the Past, a journal of the European Geosciences Union.

They looked into climate archives, data such as tree rings, ice cores, lake sediments and historical documents, to reconstruct the climate of the time. "The reconstructions show that the climatic conditions during the 1430s were very special. With its very cold winters and normal to warm summers, this decade is a one of a kind in the 400 years of data we were investigating, from 1300 to 1700 CE," says Keller. "What cannot be answered by the reconstructions alone, however, is its origin -- was the anomalous climate forced by external influences, such as volcanism or changes in solar activity, or was it simply the random result of natural variability inherent to the climate system?"

There have been other cold periods in Europe's history. In 1815, the volcano Mount Tambora spewed large quantities of ash and particles into the atmosphere, blocking enough sunlight to significantly reduce temperatures in Europe and other parts of the world. But the 1430s were different, not only in what caused the cooling but also because they hadn't been studied in detail until now.

The climate simulations ran by Keller and her team showed that, while there were some volcanic eruptions and changes in solar activity around that time, these could not explain the climate pattern of the 1430s. The climate models showed instead that these conditions were due to natural variations in the climate system, a combination of natural factors that occurred by chance and meant Europe had very cold winters and normal to warm summers.

Regardless of the underlying causes of the odd climate, the 1430s were "a cruel period" for those who lived through those years, says Camenisch. "Due to this cluster of extremely cold winters with low temperatures lasting until April and May, the growing grain was damaged, as well as the vineyards and other agricultural production. Therefore, there were considerable harvest failures in many places in northwestern and central Europe. These harvest failures led to rising food prices and consequently subsistence crisis and famine. Furthermore, epidemic diseases raged in many places. Famine and epidemics led to an increase of the mortality rate." In the paper, the authors also mention other impacts: "In the context of the crisis, minorities were blamed for harsh climatic conditions, rising food prices, famine and plague." However, in some cities, such as Basel, Strasbourg, Cologne or London, societies adapted more constructively to the crisis by building communal granaries that made them more resilient to future food shortages.

Keller says another decade of very cold winters could happen again. "However, such temperature variations have to be seen in the context of the state of the climate system. Compared to the 15th century we live in a distinctly warmer world. As a consequence, we are affected by climate extremes in a different way -- cold extremes are less cold, hot extremes are even hotter."

The team says their Climate of the Past study could help people today by showing how societies can be affected by extreme climate conditions, and how they should take precautions to make themselves less vulnerable to them. In the 1430s, people had not been exposed to such extreme conditions before and were unprepared to deal with the consequences.

Read more at Science Daily

6,000 years ago the Sahara Desert was tropical, so what happened?

The Sahara desert was once a tropical jungle.

As little as 6,000 years ago, the vast Sahara Desert was covered in grassland that received plenty of rainfall, but shifts in the world's weather patterns abruptly transformed the vegetated region into some of the driest land on Earth. A Texas A&M university researcher is trying to uncover the clues responsible for this enormous climate transformation -- and the findings could lead to better rainfall predictions worldwide.

Robert Korty, associate professor in the Department of Atmospheric Sciences, along with colleague William Boos of Yale University, have had their work published in the current issue of Nature Geoscience.

The two researchers have looked into precipitation patterns of the Holocene era nd compared them with present-day movements of the intertropical convergence zone, a large region of intense tropical rainfall. Using computer models and other data, the researchers found links to rainfall patterns thousands of years ago.

"The framework we developed helps us understand why the heaviest tropical rain belts set up where they do," Korty explains.

"Tropical rain belts are tied to what happens elsewhere in the world through the Hadley circulation, but it won't predict changes elsewhere directly, as the chain of events is very complex. But it is a step toward that goal."

The Hadley circulation is a tropical atmospheric circulation that rises near the equator. It is linked to the subtropical trade winds, tropical rainbelts, and affects the position of severe storms, hurricanes, and the jet stream. Where it descends in the subtropics, it can create desert-like conditions. The majority of Earth's arid regions are located in areas beneath the descending parts of the Hadley circulation.

"We know that 6,000 years ago, what is now the Sahara Desert was a rainy place," Korty adds.

"It has been something of a mystery to understand how the tropical rain belt moved so far north of the equator. Our findings show that that large migrations in rainfall can occur in one part of the globe even while the belt doesn't move much elsewhere.

"This framework may also be useful in predicting the details of how tropical rain bands tend to shift during modern-day El Niño and La Niña events (the cooling or warming of waters in the central Pacific Ocean which tend to influence weather patterns around the world)."

The findings could lead to better ways to predict future rainfall patterns in parts of the world, Korty believes.

Read mroe at Science Daily

Corals much older than previously thought, study finds

Acropora palmata is listed as threatened under the US Endangered Species Act.

Coral genotypes can survive for thousands of years, possibly making them the longest-lived animals in the world, according to researchers at Penn State, the National Marine Fisheries Service and Dial Cordy & Associates.

The team recently determined the ages of elkhorn corals -- Acropora palmata -- in Florida and the Caribbean and estimated the oldest genotypes to be over 5,000 years old. The results are useful for understanding how corals will respond to current and future environmental change.

"Our study shows, on the one hand, that some Acropora palmata genotypes have been around for a long time and have survived many environmental changes, including sea-level changes, storms, sedimentation events and so on," said Iliana Baums, associate professor of biology, Penn State. "This is good news because it indicates that they can be very resilient. On the other hand, the species we studied is now listed as threatened under the U.S. Endangered Species Act because it has suffered such sharp population declines, indicating that there are limits to how much change even these very resilient corals can handle."

According to Baums, many people mistake corals for plants or even non-living rocks, but corals actually consist of colonies of individual invertebrate animals living symbiotically with photosynthetic algae.

"Previously, corals have been aged by investigating the skeletons of the colonies or the sizes of the colonies," she said. "For example, bigger colonies were thought to be older. However many coral species reproduce via fragmentation, in which small pieces break off from large colonies. These pieces look like young corals because they are small, but their genomes are just as old as the big colony from which they broke. Similarly, the big colonies appear younger than their true age because they became smaller during the process of fragmentation."

Now, for the first time, Baums and her colleagues have used a genetic approach to estimate the ages of corals. The method determines when the egg and the sperm originally met to form the genome of the coral colonies. The researchers then tracked the number of mutations that accumulated in the genome since that time. Because mutations tend to arise at a relatively constant rate, the researchers were able to estimate an approximate age in calendar years of the coral genomes in their study.

The results, which appear in print in the November 2016 issue of the journal Molecular Ecology, suggest that some Acropora palmata genomes have been around for over 5,000 years.

Read more at Science Daily

Early Humans Spent More Time in Trees Than We Thought

Our ancestor "Lucy" spent at least a third of her life in trees 3.18 million years ago, according to new research that could help explain how our species evolved brain power over brawn.

Lucy (Australopithecus afarensis) turns out to have been built like a muscular champion tree-climbing chimpanzee in her upper body, but she walked on two legs, concludes the new study, published in PLOS ONE.

"Lucy probably walked on the ground in a way similar to us, but with more side-to-side sway with each step," lead author Christopher Ruff, a professor of functional anatomy and evolution at the John Hopkins University School of Medicine, told Seeker. "This would have taken more energy, and may have limited her ability to travel long distances on the ground."

Using CT scans, Ruff and his team analyzed the internal structure of Lucy's upper arm bones and thigh bones. Lucy's remains, found in the Afar region of Ethiopia 42 years ago this month, represent one of the most complete fossil skeletons ever found of any adult, erect-walking human ancestor.

The researchers next compared Lucy's scans to those of Paleolithic and modern humans, who spend the majority of their time walking on two legs on the ground, and with chimpanzees, which spend more of their time in trees. When on terra firma, chimps usually walk on all four limbs.

Lucy's upper limbs were heavily built because they were often used for tree climbing, Ruff and his colleagues concluded. Our species, on the other hand, tends to have more heavily built lower limbs, although certain athletes also have impressive upper body strength.

"Lucy would not have looked more like a modern gymnast, necessarily, although her ratio of arm to leg bone strength would have been more similar to a gymnast than to other people," Ruff said.

A day in the life of Lucy might have gone like this:

"Like modern African apes, she likely spent a good deal of time during the day on the ground, foraging, resting and traveling—at least short distances," Ruff said. "Some food items, including many fruits, were likely obtained by climbing trees. Trees would likely also have been used for sleeping, again as in modern African apes."

To this day, diets including plenty of tree-sourced items, such as nuts and fruits, are often recommended. And if you feel comforted by trees, that attraction could go way back to Lucy, who probably slept for around eight hours a night in them.

Lucy's story doesn't have a happy ending, though. She died before reaching old age, from injuries sustained after falling out of a tree. So it's possible that our ancestor's transition from tree-swinging apes to terrestrial beings went through some awkward stages.

Read more at Discovery News

Queen Nefertari's Dismembered Legs Have Been Found

A pair of unimpressive mummified legs on display in an Italian museum may belong to one of antiquity's most beautiful women, according to an international team of researchers who have analyzed the more than 3,200-year-old remains for the first time.

Consisting of fragmented thigh bones, kneecap and a proximal tibia part (the upper portion of the bone where it widens to help form the knee joint), the body parts are likely those of Queen Nefertari.

Not to be confused with Nefertiti, who lived one Dynasty earlier, Nefertari was the first and favorite wife of the mighty warrior pharaoh Ramses II, who reigned between 1290-1224 BC during the early 19th Dynasty.

"She is the only queen from the Ramesside era to have been likely identified so far," Egyptologist Michael Habicht at the Institute of Evolutionary Medicine, University of Zurich, Switzerland, told Seeker.

The study, detailed in the journal PLOS ONE, indicates the ancient Egyptian beauty was very slim and tall. The information helps reconstruct the life of one of the most intriguing figures of ancient Egypt.

"Nefertari is one of the truly great and important queens of Egypt and plays in the league of Hatshepsut, Nefertiti and Cleopatra," Habicht said.

Tomb wall depicting Queen Nefertari.

Known for the impressive wall paintings of her lavishly decorated tomb in the Valley of the Queens, which depict her timeless beauty in unusually lifelike form, Nefertari was highly educated and played an active role in foreign politics.

However, little is known about her demise.

"We know that she gave birth to four sons and four daughters and that she attended the opening ceremony of the rock-cut temples of Abu Simbel in the year 24 of Ramses II's reign. After that event, she disappeared from history," Habicht said.

Egyptologists estimate she probably died around her husband's 25th year of reign, having reached an age of about 40 to 50 years.

Nefertari's tomb, known as QV66, was heavily plundered in antiquity and her mummy was ripped to pieces and tossed around by the ancient robbers.

When Italian diplomat and archaeologist Ernesto Schiaparelli opened the queen's burial in 1904, he found a series of broken remains, including fragments of the pink granite sarcophagus that once held Nefertari's mummy, a pair of sandals and two fragmented mummified legs.

Housed at the Egyptian Museum in Turin, Italy, the remains have now been investigated in a multidisciplinary study.

"Although no absolute certainty exists, the results speak in favor of an identification of the remains as Nefertari's," lead author Frank Rühli, head of the Institute of Evolutionary Medicine at the University of Zurich in Switzerland, told Seeker.

Anthropometric reconstruction and assessment of the size of the knees revealed they belonged to a woman whose stature ranged between 165 cm (5 foot 5 inches) and 168 cm (5 foot 6 inches).

The body height was also independently estimated by professor Maciej Henneberg at the University of Adelaide, Australia, who obtained the same results — a stature of about 165 cm.

"Data about women from the New Kingdom and 3rd Intermediate Period show she was probably taller than 84 percent of the women of her time," Rühli said.

Analysis of the materials used for embalming showed they were consistent with Ramesside mummification traditions, while X-rays of the left knee pointed to possible traces of arteriosclerosis, suggesting the legs belonged to an elderly person.

"The accumulated evidence could point to an individual between 40 and 60 years old," Rühli and colleagues wrote.

A pair of sandals found in Queen Nefertari's tomb

The mystery over the mummified legs, however, is not completely solved. The authors admit the identification can't be done with absolute certainty as some analysis failed. Moreover, QV66 is not an original undisturbed burial situation.

DNA testing was inconclusive since the samples turned to be contaminated and not suitable for analysis, while radiocarbon dating of the remains yielded odd results — the remains would predate the assumed lifespan of Queen Nefertari's by some 200 years.

"A discrepancy between radiocarbon dating and Egyptian chronology models has long been debated. Indeed, some question on the chronological model of the New Kingdom may now arise," Habicht said.

"For the future, we strongly suggest radiocarbon dating of other royal and non-royal remains of the Ramesside era, in order to validate or disprove the chronology," he added.

Nefertari's tomb also contained a pair of sandals made of vegetal material — grass, palm leaf and papyrus — in a style typical of the 18th-19th Dynasties.

According to the researchers, the fine quality and shape of the sandals suggest they were royal footwear.

They estimated the shoe size to be 39-40 (US size 9), fit an individual of Nefertari's stature.

André Veldmeijer, visiting research scholar at the American University in Cairo, agrees on the sandal' size.

"The area of the foot, if the sandal would fit neatly, would reach slightly beyond the front strap, say about 24-25 cm (9.4-9.5 inches) This would indeed result in size somewhere 39 to 40," Veldmeijer, an authority on ancient footwear, told Seeker.

Read more at Discovery News

Quantum 'Ghosts' Seen in Neutron Star's Extreme Magnetism

According to quantum physics, the vacuum of space isn't really empty — virtual particles pop in and out of existence even in the emptiest of empty voids. These "virtual" particles may sound like ghostly apparitions, but now astronomers think they've spotted the interference caused by virtual particles in the dim light generated by a dense stellar nugget of degenerate matter.

This nugget is a nearby neutron star called RX J1856.5-3754, located some 400 light-years away, and researchers using the ESO's Very Large Telescope (VLT) high in the Atacama Desert in Chile have, for the first time, detected a quantum effect that was first predicted in the 1930s. This effect is known as "vacuum birefringence" and possible observational evidence of it in action could have a profound impact on our understanding of how the universe works.

It may sound strange that we can measure quantum effects near the surface of a neutron star hundreds of light-years away, but often we have to look at some of the most extreme natural "laboratories" deep in the cosmos to stand a chance of glimpsing minuscule physics that has a huge effect on astronomical data. And in the case of RX J1856.5-3754, its powerful magnetic field is thought to have manipulated virtual particles fizzing in and out of the vacuum to create a prism-like effect on the faint light generated by the neutron star.

Virtual particles underpin many curious theories in astrophysics, particularly the mechanism behind Hawking radiation — a neat theory put forward by physicist Stephen Hawking in the 1970s that suggests black holes may evaporate. Whether black holes evaporate or that virtual particles have a role to play is a matter of heated debate, but the way these ghostly quantum apparitions interact with magnetic fields can have observational effects.

In classical physics, if light travels through a vacuum, it will remain unchanged. However, if QED hold true and virtual particles are present in the vacuum immediately surrounding a neutron star, the magnetic field will interact with virtual particles to manipulate light as it travels through. This effect is predicted by "quantum electrodynamics," otherwise known as "QED."

In this case, the VLT has detected a strange polarization of light coming from the neutron star, suggesting vacuum birefringence is at play.

"According to QED, a highly magnetized vacuum behaves as a prism for the propagation of light, an effect known as vacuum birefringence," said lead researcher Roberto Mignani, of INAF Milan in Italy and the University of Zielona Gora in Poland. Mignani's tem's research will be published in the journal Monthly Notices of the Royal Astronomical Society.

"This effect can be detected only in the presence of enormously strong magnetic fields, such as those around neutron stars," added Roberto Turolla of the University of Padua, Italy. "This shows, once more, that neutron stars are invaluable laboratories in which to study the fundamental laws of nature."

Neutron stars are the remnants of stars around ten-times the mass of our sun. When these stars run out of hydrogen fuel, they explode as spectacular supernovas. What's left behind is a tiny and extremely dense sphere of mainly neutrons. Interestingly, these neutron stars retain the angular momentum and magnetism of their parent stars, only on a much more extreme scale. Pulsars are rapidly spinning neutron stars and these are known as the most precise "clocks" in the universe, flashing at a very steady rate. These factors make neutron stars ideal locations for astronomers to measure the effects of general relativity and strong magnetism.

Read more at Discovery News

Platypus venom could hold key to diabetes treatment

Platypus

Australian researchers have discovered remarkable evolutionary changes to insulin regulation in two of the nation's most iconic native animal species -- the platypus and the echidna -- which could pave the way for new treatments for type 2 diabetes in humans.

The findings, now published in the Nature journal Scientific Reports, reveal that the same hormone produced in the gut of the platypus to regulate blood glucose is also surprisingly produced in their venom.

The research is led by Professor Frank Grutzner at the University of Adelaide and Associate Professor Briony Forbes at Flinders University.

The hormone, known as glucagon-like peptide-1 (GLP-1), is normally secreted in the gut of both humans and animals, stimulating the release of insulin to lower blood glucose.

But GLP-1 typically degrades within minutes.

In people with type 2 diabetes, the short stimulus triggered by GLP-1 isn't sufficient to maintain a proper blood sugar balance. As a result, medication that includes a longer lasting form of the hormone is needed to help provide an extended release of insulin.

"Our research team has discovered that monotremes -- our iconic platypus and echidna -- have evolved changes in the hormone GLP-1 that make it resistant to the rapid degradation normally seen in humans," says co-lead author Professor Frank Grutzner, from the University of Adelaide's School of Biological Sciences and the Robinson Research Institute.

"We've found that GLP-1 is degraded in monotremes by a completely different mechanism. Further analysis of the genetics of monotremes reveals that there seems to be a kind of molecular warfare going on between the function of GLP-1, which is produced in the gut but surprisingly also in their venom," he says.

The platypus produces a powerful venom during breeding season, which is used in competition among males for females.

"We've discovered conflicting functions of GLP-1 in the platypus: in the gut as a regulator of blood glucose, and in venom to fend off other platypus males during breeding season. This tug of war between the different functions has resulted in dramatic changes in the GLP-1 system," says co-lead author Associate Professor Briony Forbes, from Flinders University's School of Medicine.

"The function in venom has most likely triggered the evolution of a stable form of GLP-1 in monotremes. Excitingly, stable GLP-1 molecules are highly desirable as potential type 2 diabetes treatments," she says.

Professor Grutzner says: "This is an amazing example of how millions of years of evolution can shape molecules and optimise their function.

"These findings have the potential to inform diabetes treatment, one of our greatest health challenges, although exactly how we can convert this finding into a treatment will need to be the subject of future research."

Read more at Science Daily

New Pyramid in Antarctica? Not Quite...

An Antarctic mountain with a unique, pyramid-like shape is suddenly internet-famous, with countless theorists contemplating its origin. Some are wondering whether an ancient civilization created the rocky, pyramidal structure, and others are pointing toward outer space, speculating about the involvement of aliens.

But Occam's razor — the idea that the simplest explanation is usually the right one — points to a far more mundane cause: Those steep, pyramid-like sides are likely the work of hundreds of millions of years of erosion, experts told Live Science.

"This is just a mountain that looks like a pyramid," Eric Rignot, a professor of Earth system science at the University of California, Irvine, told Live Science in an email. "Pyramid shapes are not impossible — many peaks partially look like pyramids, but they only have one to two faces like that, rarely four."

The pyramidal mountain, which doesn't have a formal name, is one of the many peaks that make up Antarctica's Ellsworth Mountains, which were discovered by the American aviator Lincoln Ellsworth during a flight on Nov. 23, 1935, according to a 2007 research paper that was published by the U.S. Geological Survey (USGS).

More specifically, the unnamed mountain — located at 79°58'39.25"S 81°57'32.21"W — is in the southern part of the Ellsworth Mountains in an area called Heritage Range, which is known for its extraordinary fossils, including those of Cambrian-period trilobites from more than 500 million years ago, according to a 1972 USGS report.

The mountain isn't that tall by planetary standards — just 4,150 feet (1,265 meters) — or a little less than one-fifth the height of Denali, the tallest mountain in North America, according to Google Earth. The mountain may not have Denali's height, but its unique pyramidal shape sets it apart, said Mauri Pelto, a professor of environmental science at Nichols College in Dudley, Massachusetts.

Freeze-thaw erosion likely led to its pyramid-like shape, Pelto said. This happens when snow or water fills up cracks within a mountain during the day. When night falls and temperatures drop, the snow freezes and expands, turning into ice. The expanding ice causes the cracks to grow, Pelto said.

This freeze-thaw erosion happens countless times, leading to the creation of larger cracks that can, eventually, cause entire rock sections to break off, he said. These forces likely also shaped other pyramidal mountains, including the Matterhorn in the Alps, he said.

Read more at Discovery News

This Is Your Brain on God

How does an Evangelical Lutheran woman in Minnesota experience God compared to a member of ISIS in Afghanistan?

More than 5.8 billion people say that religion and spirituality have some influence on their lives. Yet scientists know very little about what happens in the brain when someone is having a religious experience. Why does one person feel peace, joy and positivity, while another feels motivated to carry out an act of violence? Are the same neural networks in the brain responsible for both? Or do they differ from one person to the next?

These and many other questions are the focus of new research from neuroradiologist Jeff Anderson, M.D., Ph.D., and his colleagues at the University of Utah School of Medicine. Today in the journal Social Neuroscience, they report on an imaging study that shows that having a religious or spiritual experience activates the brain's "reward circuits" in the same way that love, sex, gambling, drugs and music do.

The findings, part of the university's Religious Brain Project, have the potential for identifying how people are different and how they are the same when it comes to religion and spirituality.

"Even if the messages of our gods are different, the fact that we may feel those messages the same way in the brain is a way of fostering understanding," Anderson told Seeker.

To conduct the study, Anderson and his colleagues invited 19 Mormons — seven females and 12 males — to participate in an hourlong functional MRI scan. During the scan, the scientists asked participants to do four different tasks: rest silently, watch a video, pray and read scriptures. The session was meant to simulate a worship service and evoke a charismatic religious experience that devout Mormons call "feeling the Spirit." In these moments, people of Mormon faith feel close to God, consider those feelings a form of communicating with the divine and rely on them to make important decisions.

At various times during the scan, the scientists asked the person, "Are you feeling the Spirit?" The person would respond by pushing one of four buttons, with one meaning "not feeling it" and four meaning "very strong feeling it." The scientists also monitored the person's heart rate and respiration.

Before the scan, the participant filled out a questionnaire related to his or her personal morality, and then afterward, a scientist sat with the participant for a debriefing, allowing each one to describe his or her experience.

Almost all of them said they felt feelings similar to those they experienced during worship services, including peace and even physical sensations of warmth. Many were so filled with emotion by the end of the session, their eyes filled with tears.

"When our study participants were instructed to think about a savior, about being with their families for eternity, about their heavenly rewards, their brains and bodies physically responded," author Michael Ferguson, Ph.D., said in a press statement.

Read more at Discovery News

Methane-Eating Microbes Produce Food for Farmed Animals

Our planet is home to seven billion people. By 2050, the world's population will have ballooned to over nine billion. How to feed these people means figuring out how to feed the animals that become food.

Biotechnology company Calysta, headquartered in Menlo Park, Calif., thinks one solution involves harvesting edible protein from microbes that eat methane.

Today the company announced a partnership with Cargill, a food and agriculture company based in Minneapolis, Minn., and plans to build a gas fermentation facility on Cargill's property in Memphis, Tenn. Once the plant begins operations in late 2018, it will produce 22,000 tons of FeedKind protein. By 2020, the company wants to raise that to 220,500 tons.

"The first customers are expected to be feed manufacturers serving the fish farming industry," a spokesperson at Calysta told Seeker.

Worldwide demand for farmed fish is up. According to the Earth Policy Institute, farmed fish production by-passed beef in 2013 and it continues to rise. Feeding farmed fish remains an enormous challenge because some of the favorites, like salmon, eat only fish. But it takes two pounds of fishmeal to make one pound of salmon. Knowing this, producers have already begun to supplement feeds with vegetable matter, like soy, but it doesn't agree with a salmon's belly and can cause inflammation that leads to disease.

Calysta's FeedKind protein could be one way to feed not only farmed fish, but also cows, pigs and even household pets.

If the idea of creating food from microbes, specifically Methylococcus capsulatus bacteria, that eat methane — a gas normally associated with landfills, cow burps and manure, sounds unpalatable — you're not alone. But consider for a moment that methane is a carbon compound and that humans are carbon-based lifeforms. We are carbon; we eat carbon.

Instead of raising these organisms on industrial-scale farms that require thousands of acres of land and millions of gallons of water, Calysta will grow these microbes in bioreactor vats. The gas fermentation technology was originally invented by Statoil, a Norwegian oil and gas company, but then in 2014, Calysta bought the patents to that technology and has been refining the process ever since.

Here's how it works: the microbes, which have not been genetically modified, are added to the bioreactors along with methane, air and other microbes that eat up any of the waste products not essential to the process. Ammonia is also added because it reacts with the carbon and hydrogen in the methane in a way that produces the amino acids that make up the proteins.

As the microbes eat away at the methane, they mature, multiply and divide as single-celled creatures are wont to do. Eventually they're ready to be harvested and at that time, each organism is more than 70 percent protein by weight. Not bad. After harvest, they're dried, powered and turned into pellets.

Feeding these pellets to farmed fish and livestock has already been approved in the European Union, and this past September Calysta set up a factory in Teesside, U.K., but Calysta will have to get the same approval in the United States. Until then, the plant in Memphis will sell FeedKind pellets to fish farmers in Asia and Europe.

At the moment, the environmental benefits of producing FeedKind protein has mixed results. The cheapest source of methane doesn't come from renewable sources, such landfills, farms with excess manure or anaerobic digesters. It comes from the natural gas industry.

Read more at Discovery News

Electric Blue Clouds Make Early Arrival Over South Pole

The sky above Antarctica is glowing electric blue and the appearance of the seasonal noctilucent clouds is among the earliest on record.

Noctilucent clouds — which means "night-shining" clouds in Latin — are made of tiny crystals of ice that form near the edge of space, about 50 miles above Earth. They can be seen during deep twilight during the summer months between 50 degrees and 70 degrees north or south of the equator. (It's now summer in the southern hemisphere.)

Scientists using NASA's Aeronomy of Ice in the Mesosphere (AIM) satellite report that the discovery of noctilucent clouds over Antarctica on Nov. 17 ties 2013 for the clouds' earliest appearance.

A paper published in the March 2016 edition of the Journal of Geophysical Research suggests the clouds are appearing more frequently and are brighter due to climate change.

"The southern hemisphere polar stratospheric winds switched to their summer-like state quite early this year," said AIM scientist Cora Randall, with the University of Colorado. "The early start of the 2016 season was not at all a surprise."

NASA says noctilucent clouds form during the summer due to wind patterns and the flow of atmospheric humidity. More water molecules reach the upper atmosphere during summer, allowing some to mix with bits of meteoroids at the edge of space, which seed the clouds. Summer also is when the temperature of the upper atmosphere is coldest, allowing ice crystals to form.

"In recent years noctilucent clouds have intensified and spread. When noctilucent clouds first appeared in the 19th century, you had to travel to polar regions to see them. Since the turn of the century, however, they have been sighted as close to the equator as Colorado and Utah," NASA said in a 2013 press release.

One reason this may be happening is due to a greater concentration of the greenhouse gas methane, which becomes oxidized by a complex series of reactions to form water vapor, according to AIM lead scientist James Russell, with Hampton University.

The extra water vapor is available to grow ice crystals, which eventually form into noctilucent clouds.

From Discovery News

Timing the shadow of a potentially habitable extrasolar planet paves the way to search for alien life

By observing its transit precisely using the next generation of telescopes, scientists expect to be able to search the atmosphere of the planet for molecules related to life, such as oxygen.

A group of researchers from the National Astronomical Observatory of Japan (NAOJ), the University of Tokyo, and the Astrobiology Center among others has observed the transit of a potentially Earth-like extrasolar planet known as K2-3d using the MuSCAT instrument on the Okayama Astrophysical Observatory 188-cm telescope. A transit is a phenomenon in which a planet passes in front of its parent star, blocking a small amount of light from the star, like a shadow of the planet. While transits have previously been observed for thousands of other extrasolar planets, K2-3d is important because there is a possibility that it might harbor extraterrestrial life.

By observing its transit precisely using the next generation of telescopes, such as TMT, scientists expect to be able to search the atmosphere of the planet for molecules related to life, such as oxygen.

With only the previous space telescope observations, however, researchers can't calculate the orbital period of the planet precisely, which makes predicting the exact times of future transits more difficult. This research group has succeeded in measuring the orbital period of the planet with a high precision of about 18 seconds. This greatly improved the forecast accuracy for future transit times. So now researchers will know exactly when to watch for the transits using the next generation of telescopes. This research result is an important step towards the search for extraterrestrial life in the future.

K2-3d

K2-3d is an extrasolar planet about 150 light-years away that was discovered by the NASA K2 mission (the Kepler telescope's "second light") (Note 1). K2-3d's size is 1.5 times the size of the Earth. The planet orbits its host star, which is half the size of the Sun, with a period of about 45 days. Compared to the Earth, the planet orbits close to its host star (about 1/5 of the Earth-Sun distance). But, because the temperature of the host star is lower than that of the Sun, calculations show that this is the right distance for the planet to have a relatively warm climate like the Earth's. There is a possibility that liquid water could exist on the surface of the planet, raising the tantalizing possibility of extraterrestrial life.

K2-3d's orbit is aligned so that as seen from Earth, it transits (passes in front of) its host star. This causes, short, periodic decreases in the star's brightness, as the planet blocks some of the star's light. This alignment enables researchers to probe the atmospheric composition of these planets by precise measurement of the amount of blocked starlight at different wavelengths.

About 30 potentially habitable planets that also have transiting orbits were discovered by the NASA Kepler mission, but most of these planets orbit fainter, more distant stars. Because it is closer to Earth and its host star is brighter, K2-3d is a more interesting candidate for detailed follow-up studies. The brightness decrease of the host star caused by the transit of K2-3d is small, only 0.07%. However, it is expected that the next generation of large telescopes will be able to measure how this brightness decrease varies with wavelength, enabling investigations of the composition of the planet's atmosphere. If extraterrestrial life exists on K2-3d, scientists hope to be able to detect molecules related to it, such as oxygen, in the atmosphere.

MuSCAT Observations and Transit Ephemeris Improvements

The orbital period of K2-3d is about 45 days. Since the K2 mission's survey period is only 80 days for each area of sky, researchers could only measure two transits in the K2 data. This isn't sufficient to measure the planet's orbital period precisely, so when researchers attempt to predict the times of future transits, creating something called a "transit ephemeris," there are uncertainties in the predicted times. These uncertainties grow larger as they try to predict farther into the future. Therefore, early additional transit observations and adjustments to the ephemeris were required before researchers lost track of the transit. Because of the importance of K2-3d, the Spitzer Space Telescope observed two transits soon after the planet's discovery, bringing the total to four transit measurements. However, the addition of even a single transit measurement farther in the future can help to yield a significantly improved ephemeris.

Using the Okayama 188-cm Reflector Telescope and the latest observational instrument MuSCAT, the team observed a transit of K2-3d for the first time with a ground based telescope. Though a 0.07% brightness decrease is near the limit of what can be observed with ground based telescopes, MuSCAT's ability to observe three wavelength bands simultaneously enhanced its ability to detect the transit. By reanalyzing the data from K2 and Spitzer in combination with this new observation, researchers have greatly improved the precision of the ephemeris, determining the orbital period of the planet to within about 18 seconds (1/30 of the original uncertainty). This improved transit ephemeris ensures that when the next generation of large telescopes come online, they will know exactly when to watch for transits. Thus these research results help pave the way for future extraterrestrial life surveys.

Read more at Science Daily

Biggest exposed fault on Earth discovered

Geologists have for the first time seen and documented the Banda Detachment fault in eastern Indonesia and worked out how it formed.

Geologists have for the first time seen and documented the Banda Detachment fault in eastern Indonesia and worked out how it formed.

Lead researcher Dr Jonathan Pownall from The Australian National University (ANU) said the find will help researchers assess dangers of future tsunamis in the area, which is part of the Ring of Fire -- an area around the Pacific Ocean basin known for earthquakes and volcanic eruptions.

"The abyss has been known for 90 years but until now no one has been able to explain how it got so deep," Dr Pownall said.

"Our research found that a 7 km-deep abyss beneath the Banda Sea off eastern Indonesia was formed by extension along what might be Earth's largest-identified exposed fault plane."

By analysing high-resolution maps of the Banda Sea floor, geologists from ANU and Royal Holloway University of London found the rocks flooring the seas are cut by hundreds of straight parallel scars.

These wounds show that a piece of crust bigger than Belgium or Tasmania must have been ripped apart by 120 km of extension along a low-angle crack, or detachment fault, to form the present-day ocean-floor depression.

Dr Pownall said this fault, the Banda Detachment, represents a rip in the ocean floor exposed over 60,000 square kilometres.

"The discovery will help explain how one of Earth's deepest sea areas became so deep," he said.

Professor Gordon Lister also from the ANU Research School of Earth Sciences said this was the first time the fault has been seen and documented by researchers.

"We had made a good argument for the existence of this fault we named the Banda Detachment based on the bathymetry data and on knowledge of the regional geology," said Professor Lister.

Dr Pownall said he was on a boat journey in eastern Indonesia in July when he noticed the prominent landforms consistent with surface extensions of the fault line.

"I was stunned to see the hypothesised fault plane, this time not on a computer screen, but poking above the waves," said Dr Pownall.

He said rocks immediately below the fault include those brought up from the mantle.

"This demonstrates the extreme amount of extension that must have taken place as the oceanic crust was thinned, in some places to zero," he said.

Dr Pownall also said the discovery of the Banda Detachment fault would help assesses dangers of future tsunamis and earthquakes.

Read more at Science Daily

What Will We Do When Hubble Dies?

For a generation, the Hubble Space Telescope has been exposing the universe's deepest, darkest secrets. From imaging the volcanoes of Jupiter's moon Io, to watching the dramatic breakup of comets, imaging baby galaxies, and helping to nail down the universe's age, its data has been instrumental in today's understanding of the cosmos near and far.

But it's an old telescope, unmaintained since the last space shuttle mission visited in 2009. While the observatory is in excellent health today, it's expected to stop collecting data sometime in the 2020s. What will we lose when the telescope finally dies?

NASA is quick to point out that the James Webb Space Telescope, expected to launch in 2018, will enhance Hubble's capabilities in many ways. But for the telescope's higher resolution and ability to peer back to the very early days of the universe, there is one key thing it doesn't have: ultraviolet capabilities. (It also will lack some of Hubble's fine spectral resolution, and ability to observe a special spectral line called H-alpha that is useful for nebulae and stars.)

Astronomers are being urged to submit as many UV proposals to Hubble as possible because once it dies, there are no immediate plans to launch a successor. (Astronomers could then pull from the archive as needed in future decades.) Earth's atmosphere filters out UV, which is great for protecting life, but bad for UV astronomy, so it needs to be done from space. Astronomers say they don't think another UV telescope will fly until the 2030s, at the earliest.

"For example, one of the big topics that we're going to look at in star and planet formation is the accretion of gas on to young, newly forming stars or planets," said Adam Kraus, an astronomer at the University of Texas at Austin. He explained that as gas falls on to budding stars and planets, they radiate most of their energy in the blue and ultraviolet wavelengths. Webb won't be able to see this as Hubble does, he told Seeker.

The James Webb Space Telescope (pictured here during a mirror inspection) will enhance Hubble's observations in many areas, but it lacks in ultraviolet capabilities.

NASA's Jane Rigby, the deputy project scientist for Webb's operations, points out that the new telescope is designed to do science that Hubble can't. Webb has seven times more collecting area and also works at near absolute zero (the coldest temperature possible). Hubble works at room temperature, so it can't see as well in the infrared. Webb will see into dusty places where stars are forming, or galaxies that have been deeply "redshifted" (with spectral lines moving towards the red end of the spectrum) due to cosmic expansion.

Luckily for astronomers, it's expected that Hubble's and Webb's time in space will overlap. Hubble has a rich archive of observations that Webb could spend time looking at, including the famous "deep fields" of young galaxies. This type of work will be Webb's "bread and butter", Rigby said.

There's also the potential to make stereoscopic or "3D" images of several objects, since Hubble (in low Earth orbit) will be a million miles away from Webb, further out in space. At the Space Telescope Science Institute (STScI), which manages Hubble observations, some astronomers suggest images could be taken of nearby objects.

"You could see Saturn's rings sticking out of the page, Mars looking like a globe, or Jupiter and its moons moving," Joel Green, a project scientist at STScI, told Seeker. "There's a few scientific reasons, too. You might want to look at how cloud structures change in 3D, or how an impact happens in 3D."

Another possibility, he added, would be looking at a star explosion (or supernova) and from the distance between the telescopes, finding out where the explosion is coming from and examining certain features of the explosion.

Hubble's ultraviolet capabilities are not replicated in any telescope now, or in the near future. Here, possible water plumes on Europa (disclosed earlier this year) are imaged using Hubble's ultraviolet filters.

Other observatories are planned after Webb. One is the Wide Field Infrared Survey Telescope (WFIRST), which would use Hubble-class hardware that has a wider field of view. Its specialty would be dark energy and exoplanets. Another is the Transiting Exoplanet Survey Satellite (TESS), which would look at planets passing in front of the brightest stars in our sky. These likely would get going in the 2020s, if funding for the missions is fully approved.

But the next generation is still being worked out. NASA draws heavily from the National Science Foundation's Decadal Survey when planning its missions. Right now, proposals are being formulated to present to members of the next decadal survey, which will be released in 2020.

Read more at Discovery News

Gruesome Rituals Revealed in 9,500-Year-Old Graves

Gruesome evidence of funerary rituals that involved mutilation, removal of muscles and teeth, and possibly cannibalism of fresh corpses has been uncovered in Brazil, according to an international team of researchers.

Unearthed at Lapa do Santo, a cave in east-central Brazil, the 9,500-year-old remains provide the oldest documentation of humans performing complex funerary rituals in the region.

"In the absence of monumental architecture or grave goods, parts of fresh corpses were used in elaborate rituals," André Strauss, at the Erberhard-Karls Universität in Tübingen, Germany, said.

Starting between 10,000 and 10,600 years ago, Lapa do Santo was used as a place of burial of complete bodies. Between 9,400 and 9,600 years ago more complex funerary rituals took place, featuring what Strauss and colleagues call "manipulation" and "reduction" of the corpses.

Such techniques included "mutilation, defleshing, tooth removal, exposure to fire and possibly cannibalism," the researchers wrote in the journal Antiquity.

This skull shows burnt traces and intentional removal of teeth

Strauss and colleagues investigated 26 human burials. They were surprised by the diversity and complexity of the remains in a region of South America where hunter-gatherer communities were assumed to be extremely simple and homogeneous.

"The burials included bones with cutting and chopping marks, exposure to fire, a head buried with amputated hands and skulls in which all teeth were intentionally removed," Strauss told Discovery News.

"In one case a skull cap was used as funerary receptacle. The mutilated and burnt bones of the same individual were deposited inside," Strauss added.

Read more at Discovery News

Theory that challenges Einstein's physics could soon be put to the test

A theory by Imperial physicists that the speed of light is variable - and not constant as Einstein suggested - could soon be put to the test.

Scientists behind a theory that the speed of light is variable -- and not constant as Einstein suggested -- have made a prediction that could be tested.

Einstein observed that the speed of light remains the same in any situation, and this meant that space and time could be different in different situations.

The assumption that the speed of light is constant, and always has been, underpins many theories in physics, such as Einstein's theory of general relativity. In particular, it plays a role in models of what happened in the very early universe, seconds after the Big Bang.

But some researchers have suggested that the speed of light could have been much higher in this early universe. Now, one of this theory's originators, Professor João Magueijo from Imperial College London, working with Dr Niayesh Afshordi at the Perimeter Institute in Canada, has made a prediction that could be used to test the theory's validity.

Structures in the universe, for example galaxies, all formed from fluctuations in the early universe -- tiny differences in density in certain regions. A record of these early fluctuations is imprinted on the cosmic microwave background -- a map of the oldest light in the universe -- in the form of a 'spectral index'.

Working with their theory that the fluctuations were influenced by a varying speed of light in the early universe, Professor Magueijo and Dr Afshordi have now used a model to put an exact figure on the spectral index. The predicted figure and the model it is based on are published in the journal Physical Review D.

Cosmologists are currently getting ever more precise readings of this figure, so that prediction could soon be tested -- either confirming or ruling out the team's model of the early universe. Their figure is a very precise 0.96478. This is close to the current estimate of readings of the cosmic microwave background, which puts it around 0.968, with some margin of error.

Professor Magueijo said: "The theory, which we first proposed in the late-1990s, has now reached a maturity point -- it has produced a testable prediction. If observations in the near future do find this number to be accurate, it could lead to a modification of Einstein's theory of gravity.

"The idea that the speed of light could be variable was radical when first proposed, but with a numerical prediction, it becomes something physicists can actually test. If true, it would mean that the laws of nature were not always the same as they are today."

The testability of the varying speed of light theory sets it apart from the more mainstream rival theory: inflation. Inflation says that the early universe went through an extremely rapid expansion phase, much faster than the current rate of expansion of the universe.

These theories are necessary to overcome what physicists call the 'horizon problem'. The universe as we see it today appears to be everywhere broadly the same, for example it has a relatively homogenous density.

This could only be true if all regions of the universe were able to influence each other. However, if the speed of light has always been the same, then not enough time has passed for light to have travelled to the edge of the universe, and 'even out' the energy.

As an analogy, to heat up a room evenly, the warm air from radiators at either end has to travel across the room and mix fully. The problem for the universe is that the 'room' -- the observed size of the universe -- appears to be too large for this to have happened in the time since it was formed.

The varying speed of light theory suggests that the speed of light was much higher in the early universe, allowing the distant edges to be connected as the universe expanded. The speed of light would have then dropped in a predictable way as the density of the universe changed. This variability led the team to the prediction published today.

Read more at Science Daily