Jun 11, 2016

Is This the World’s Oldest Computer?

An international team of scientists announced this week that they've finally sleuthed out the secrets of the world famous Antikythera Mechanism.

Well, it's world famous in archaeology circles, anyway. Discovered in a shipwreck off the coast of Greece in 1901, the Antikythera Mechanism has fascinated and puzzled scholars for more than a century. The intricate device appears to be a high-tech relic of an ancient age, a clockwork mechanism used to calculate astronomical events and other celestial happenings. Dated to around 150 BCE, it's been termed the world's oldest mechanical computer.

After more than 10 years of intensive study using cutting-edge computer scanning equipment, the research team presented new findings concerning the famous relic. Scientists have been able to decode about 3,500 characters of explanatory text -- a kind of user's manual -- that were previously indecipherable.

The tiny lettering on the device, as small as 1.2 millimeters, were engraved on inside and outward-facing panels of the device, which was originally encased in a wooden cabinet with dozens of interlocking brass gears. The deciphered language more or less confirms what archaeologists have suspected all along: The Antikythera Mechanism was designed as a clockwork calendar that showed the phases of the moon, the position of the sun and the planets, and even the time of predicted eclipses.

"It was not a research tool, something that an astronomer would use to do computations, or even an astrologer to do prognostications, but something that you would use to teach about the cosmos and our place in the cosmos," researcher Alexander Jones said at the news conference, according to an Associated Press report of the event. "It's like a textbook of astronomy as it was understood then, which connected the movements of the sky and the planets with the lives of the ancient Greeks and their environment."

This announcement caps 12 years of research in which technicians and scholars used x-ray machines and other scanning technology to analyze the 82 surviving fragments of the original device. Each individual letter in on the corroded plates was reconstructed using dozens of scans from different angles. The research team said they have now deciphered nearly all of text on the fragments, which were originally recovered by free diving sponge fishermen.

As it happens, archaeologists are currently revisiting the site of the original shipwreck -- you can read more about that here. Or check out this fabulous New Yorker piece from a few years back, which provides a nice overview of all things Antikythera.

From Discovery News

Do Blowflies Top Camera Traps for Mammal Tracking?

If you want to monitor mammal populations, how about looking in the guts of a blowfly to see where it's been, or ... on what it's been?

Researchers from the University of Malaya wanted to test the effectiveness of just that approach, so they examined blowfly gut DNA material culled from tropical forest reserves in peninsular Malaysia. They wanted to see what mammal evidence might lie within and then compare those results with traditional mammal survey approaches such as scat collection, wire cages, capture nets and camera traps.

The annoying flies are a good place to look for evidence of mammals in the neighborhood, after all. They aren't terribly choosy about their dining habits and spend time feasting on the waste, wounds and carcasses of wild animals, unwittingly becoming samplers of mammalian DNA.

According to the researchers, blowfly-gut DNA found a wider body-size range of flying and non-flying mammals, compared with more traditional approaches.

The fly guts even tipped researchers off to a near-threatened species -- a dusky leaf monkey -- that had not been detected by the usual methods.

The guts also topped camera traps -- among the most popular mammal-survey tools -- at uncovering the presence of the widest groupings of flying and tree-living creatures.

However, the team noted that different survey methods seemed to detect different mammals, suggesting that the fastest way to find the broadest range of animals was to use several methods at once.

That would mean the humble, bothersome blowfly could elevate its station in life, at least for conservation biologists.

"With further calibration," the scientists wrote, "blowfly-derived DNA may join the list of traditional field methods."

And, for the completists out there, the researchers noted that they didn't find exclusively mammal material. DNA from other vertebrates such as turtles, fish, birds, lizards and snakes were also detected from blowfly guts.

From Discovery News

Jun 10, 2016

Likely new planet may be in slow death spiral

Astronomers searching for the galaxy's youngest planets have found compelling evidence for one unlike any other, a newborn "hot Jupiter" whose outer layers are being torn away by the star it orbits every 11 hours.

"A handful of known planets are in similarly small orbits, but because this star is only 2 million years old this is one of the most extreme examples," said Rice University astronomer Christopher Johns-Krull, lead author of a new study that makes a case for a tightly orbiting gas giant around the star PTFO8-8695 in the constellation Orion. The peer-reviewed study will be published in The Astrophysical Journal and was made available online this week.

"We don't yet have absolute proof this is a planet because we don't yet have a firm measure of the planet's mass, but our observations go a long way toward verifying this really is a planet," Johns-Krull said. "We compared our evidence against every other scenario we could imagine, and the weight of the evidence suggests this is one of the youngest planets yet observed."

Dubbed "PTFO8-8695 b," the suspected planet orbits a star about 1,100 light years from Earth and is at most twice the mass of Jupiter. The team that compiled the evidence was co-led by Johns-Krull and Lowell Observatory astronomer Lisa Prato and included 10 co-authors from Rice, Lowell, the University of Texas at Austin, NASA, the California Institute of Technology and Spain's National Institute of Aerospace.

"We don't know the ultimate fate of this planet," Johns-Krull said. "It likely formed farther away from the star and has migrated in to a point where it's being destroyed. We know there are close-orbiting planets around middle-aged stars that are presumably in stable orbits. What we don't know is how quickly this young planet is going to lose its mass and whether it will lose too much to survive."

Astronomers have discovered more than 3,300 exoplanets, but almost all of them orbit middle-aged stars like the sun. On May 26, Johns-Krull, Prato and co-authors announced the discovery of 'CI Tau b,' the first exoplanet found to orbit a star so young that it still retains a disk of circumstellar gas. Johns-Krull said finding such young planets is challenging because there are relatively few candidate stars that are young enough and bright enough to view in sufficient detail with existing telescopes. The search is further complicated by the fact that young stars are often active, with visual outbursts and dimmings, strong magnetic fields and enormous starspots that can make it appear that planets exist where they do not.

PTFO8-8695 b was identified as a candidate planet in 2012 by the Palomar Transit Factory's Orion survey. The planet's orbit sometimes causes it to pass between its star and our line of sight from Earth, therefore astronomers can use a technique known as the transit method to determine both the presence and approximate radius of the planet based on how much the star dims when the planet "transits," or passes in front of the star.

"In 2012, there was no solid evidence for planets around 2 million-year-old stars," Prato said. "Light curves and variations of this star presented an intriguing technique to confirm or refute such a planet. The other thing that was very intriguing about it was that the orbital period was only 11 hours. That meant we wouldn't have to come back night after night after night, year after year after year. We could potentially see something happen in one night. So that's what we did. We just sat on the star for a whole night."

A spectroscopic analysis of the light coming from the star revealed excess emission in the H-alpha spectral line, a type of light emitted from highly energized hydrogen atoms. The team found that the H-alpha light is emitted in two components, one that matches the very small motion of the star and another than seems to orbit it.

"We saw one component of the hydrogen emission start on one side of the star's emission and then move over to the other side," Prato said. "When a planet transits a star, you can determine the orbital period of the planet and how fast it is moving toward you or away from you as it orbits. So, we said, 'If the planet is real, what is the velocity of the planet relative to the star?' And it turned out that the velocity of the planet was exactly where this extra bit of H-alpha emission was moving back and forth."

Johns-Krull said transit observations revealed that the planet is only about 3 to 4 percent the size of the star, but the H-alpha emission from the planet appears to be almost as bright as the emission coming from the star.

"There's no way something confined to the planet's surface could produce that effect," he said. "The gas has to be filling a much larger region where the gravity of the planet is no longer strong enough to hold on to it. The star's gravity takes over, and eventually the gas will fall onto the star."

Read more at Science Daily

Popcorn-like fossils provide evidence of environmental impacts on species numbers

Calcite tests of extinct species of planktonic foraminifera from the Eocene epoch (>34 million years) of Tanzania. The largest is less than a millimetre in size.
The number of species that can exist on Earth depends on how the environment changes, according to new research led by the University of Southampton.

By analysing the fossil record of microscopic aquatic creatures called planktonic foraminifera, whose fossil remains now resemble miniaturised popcorn and date back millions of years, the research provided the first statistical evidence that environmental changes put a cap on species richness.

Lead author of the study, published in the journal Ecology Letters, Dr Thomas Ezard, an evolutionary ecologist at the University of Southampton, said: "While the idea of infinite species on a finite Earth is clearly fanciful, the relevance of upper limits to diversity is still a fractious debate amongst evolutionary biologists, ecologists and palaeontologists.

"We are the first to show statistically that this upper limit is environmentally dependent. It's intuitive that a changing environment alters how many species we see -- the spatial gradient of more species in the tropics than at the poles is pervasive evidence for its large-scale impact.

"However, analyses of how species numbers have changed over time have assumed that any limit has always been the same, even through periods of massive climate upheaval. Our data reject this idea of fixed rules for competition among species and instead show that the limit to the number of species that can co-exist on Earth is much more dynamic. Climate and geology are always changing, and the limit changes with them."

While previous research typically focused individually on either biological, climate change or geological explanations, this new research examined the co-dependence of these factors on how species interact.

Looking at the fossil history of 210 evolutionary species of macroperforate planktonic foraminifera in the Cenozoic Era from 65 million years ago to the present, the study found that the number of species was almost certainly controlled by competition among themselves and probably kept within a finite upper limit.

Dr Ezard added: "We used mathematical models to reveal how environmental changes influence both the rate of diversification among species and how many species can co-exist at once. Our results suggest that the world is full of species, but that the precise fullness varies through time as environmental changes alter the outcome of competition among species."

Read more at Science Daily

Scientists Turn Carbon Dioxide Emissions to Stone

For the first time, carbon dioxide emissions from an electric power plant have been captured, pumped underground and solidified — the first step toward safe carbon capture and storage, according to a paper published Thursday in the journal Science.

"This opens another door for getting rid of carbon dioxide or storing carbon dioxide in the subsurface that really wasn't seen as a serious alternative in the past," said study co-author Martin Stute, a hydrologist at the Lamont-Doherty Earth Observatory at Columbia University in New York.

cientists working at the Hellisheidi geothermal power plant near Reykjavik, Iceland, were able to pump the plant's carbon dioxide-rich volcanic gases into deep underground basalt formations, mix them with water and chemically solidify the carbon dioxide.

When basalt — a volcanic rock that makes up roughly 70 percent of the earth's surface — is exposed to carbon dioxide and water, a chemical reaction occurs, converting the gas to a chalk-like solid material. Scientists previously thought it wasn't possible to capture and store carbon this way because earlier studies suggested it could take thousands of years for large amounts of carbon dioxide to be converted to chalk.

Scientists, working on a project called CarbFix, were able to do it in two years.

"The big surprise is that these reactions happen so quickly — even on an engineering project timescale," Stute said.

Without carbon capture and storage, or CCS, it may be impossible to keep global warming from exceeding 2°C (3.6°F),according to the Intergovernmental Panel on Climate Change.

Until now, CCS proposals have involved capturing carbon dioxide emissions at power plants, then storing them in liquid or "slurry" form underground where they would stay indefinitely.

Some scientists have said that there could be tremendous risks involved with CCS: The stored carbon dioxide could explosively leak into the atmosphere through fissures in the earth or be placed at risk by terrorism, creating a climate catastrophe.

Turning carbon emissions into stone would solve that problem.

"This is an exciting demonstration of a potentially transformational approach to CO2 storage," said Jeffrey Bielicki, an assistant engineering professor at Ohio State University who is unaffiliated with the study. "The approach binds CO2 in a way that immobilizes it on a relatively short timeline, especially when compared to the duration of time that we need to keep CO2 out of the atmosphere."

Risks that carbon dioxide will escape into the atmosphere while it is being stored underground are greatly diminished because the solidification process occurs so quickly, he said.

The catch is that scientists don't know why the carbon dioxide was solidified within two years in Iceland, or if the reactions would slow down over time. They also don't know how the process would be affected if power plants were to mix the carbon dioxide with readily available saltwater instead of fresh water.

A few more years of research are needed for scientists to answer those questions, but if the process proves viable, the climate implications are huge, Stute said.

"In the future, we could think of using this for power plants in places where there's a lot of basalt — and there are many such places," he said.

As promising as it sounds, there are many uncertainties about whether solidifying carbon dioxide emissions could be a viable part of a climate strategy, said Bert Metz, a fellow at the European Climate Foundation who is unaffiliated with the study and was the lead author of a 2005 IPCC special report on carbon capture.

Bielicki said scientists need to do more research into how different kinds of basalt affect the way carbon dioxide solidifies before the CarbFix process can be used worldwide.

Stute said the process could eventually be used for direct removal of carbon dioxide from the atmosphere, something that may become necessary if climate change proves to be more catastrophic than scientists fear.

Read more at Discovery News

Mummy Shows Ancient Egyptians Bleached Their Skin

Evidence that the ancient Egyptians plastered on killer cosmetics to whiten their skin has been found in a 3,500-year-old mummy head.

Belonging to an anonymous woman age 20-25, the head shows tiny nodules under the cheeks and at the back of the neck that point to a possible skin disorder called exogenous ochronosis.

"Such dermatosis is caused by the extensive use of skin bleaching cosmetics," ‎Despina Moissidou, an anthropologist at Nation Kapodistrian University of Athens, Greece, told Discovery News.

History suggests that a lightened tone of the skin might have made the difference in Egyptian society.

"Perhaps it was a symbol of high social status, indicating the individual did not perform hard outdoor work or work at all, just like the deformed feet or the extremely long nails for the ancient high-class Chinese women," Angel Gonzalez, a collaborator at the School of Legal Medicine in Madrid, told Discovery News.

Moissidou and colleagues at the University of Madrid and Athens presented their research at the recent International Conference of Comparative Mummy Studies in Hildesheim, Germany.

The mummified head, which currently belongs to the Museo de Antropología Médica, Forense, Paleopatología y Criminalística in Madrid, Spain, was first described as the "beheaded head of a Guinean negress young woman."

The head's true origins were found only in 2007, when Moissidou and colleagues traced the mummified remains back to the Theban Necropolis archaeological area in Egypt. The head's mummification technique made it possible to date it to the 18th Dynasty of the New Kingdom.

This is the best known ancient Egyptian dynasty as it includes several famous pharaohs, such as Hatshepsut, Amenhotep III, Akhenaten and Tutankhamun. The researchers believe the woman lived in a period between the reign of Thutmose II and Thutmose III.

The head's whereabouts are still a mystery. Its recorded history begins sometime between 1898-1930, when it appears in the Cairo Museum. The head was then sold to the Spanish collector and banker Ignacio Bauer and finally donated to the Real Sociedad de Arqueología, Antropologíay Prehistoria in Madrid.

"Looking at the accurate embalming, we can say this lady was an important member of the Egyptian society of the time," Gonzalez said.

Moissidou and colleagues carried out several examinations to confirm the diagnosis of exogenous ochronosis.

"Samples were retrieved from the base of the neck and were sent for histological examination," Moissidou said.

Read more at Discovery News

Jun 9, 2016

Weak bees make strong colonies

A Varroa mite on a honey bee pupa.
Colonies of the Eastern honey bee, the original host of parasitic Varroa destructor mites, survive infestations that are fatal to Western honey bees. A research team from Agroscope and the Institute of Bee Health at the University of Bern (both Switzerland), together with partners from Thailand and China discovered that a large proportion of infested Eastern honey bee larvae die, prompting their elimination from the colony, together with that of their parasites. Counter-intuitively, weak individuals contribute to society survival by preventing the parasite to spread. This is an example of how altruistic suicide can be favoured by nature.

There is a general consensus that the parasitic mite Varroa destructor is the greatest biological threat to the health of Western honey bees, globally. This parasite endangers honey bee survival, which may in turn negatively impact pollination services crucial to food security and to the maintenance of biodiversity.

"Sustainable control of this parasite is hampered by our limited understanding of how the original host of this mite, the Eastern honey bee, defends itself," says senior author Vincent Dietemann from Agroscope. "With this study, we wanted identify resistance factors that allow colonies of the Eastern honey bees to control and survive infestations of this parasite," adds lead author Paul Page from both Agroscope and Institute of Bee Health at the University of Bern, who has been working on this project for the past three years.

A joint research team from Agroscope at the Swiss Confederation and from the Institute of Bee Health at the University of Bern (Switzerland), together with partners from Chiang Mai University (Thailand) and Zhejiang University (China), recently reported a newly identified behavior and a previously unknown purpose of altruistic suicide in the Eastern honey bee in an article in the open-access journal Scientific Reports (Nature Publishing Group).

"The behavior is comparable to that of honey bee workers that lose their lives when they defend their colonies. Their sting apparatus detaches from their body to remain in the intruder, which results in a fatal hemorrhage," explains Zheguang Lin from Zhejiang University, who also contributed to the work.

The nature of the new evidence is experimental and based on the observation of individual susceptibility to parasitism. Infested larvae of the Eastern honey bee are more susceptible to Varroa mites compared to A. mellifera and die faster. This observation suggests that this weakness has evolved to enable more efficient social immunity. Indeed, weak and dead larvae, together with their parasites, are expelled from the colony by their siblings, preventing the mites to spread. The greater susceptibility of individuals to infestation, although leading to their death, is favored by natural selection since colony survival is increased.

Understanding insect societies and application for beekeeping

The findings are significant for those studying sociality in insects since they shed a new light on how individuals cooperate in the face of parasitism: it is not necessarily "strong" individuals that foster the survival of a colony of honey bees, but counter-intuitively, it might be that it is the "weak" (i.e. susceptible) individuals that do. The results also have major field implications for beekeepers. Over the past 20 years, breeding attempts for Western honey bee survival in the presence of the parasite has not yielded a satisfying solution. Co-author Peter Neumann from the Institute of Bee Health states "considering individual susceptibility in breeding programs will improve colony health and contribute to a more sustainable global apiculture."

Honey bee diseases and pollination -- Background

Honey bee colonies are attractive heavens for numerous organisms. The close proximity of thousands of hosts in a small, warm and humid nest provides ideal conditions for numerous parasites or pathogens to develop and thrive. With the global trade of honey bees, natural boundaries between species are overcome and parasites and pathogens specific to particular species are put into contact with new potential host species that lack natural defenses against them. The Varroa mite has thus benefited from human activities to reach a near worldwide distribution within a century.

Read more at Science Daily

Rust under pressure could explain deep Earth anomalies

An artwork depicting the decomposition of FeOOH in lower mantle conditions. The cycle starts from ?-FeOOH (blue dot on the top) to its high-pressure form (brown dot), to FeO2 (center crystal) and hydrogen (cyan bubbles), and finally produce other minerals (bubbles on the left side).
Using laboratory techniques to mimic the conditions found deep inside Earth, a team of Carnegie scientists led by Ho-Kwang "Dave" Mao has identified a form of iron oxide that they believe could explain seismic and geothermal signatures in the deep mantle. Their work is published in Nature.

Iron and oxygen are two of the most geochemically important elements on Earth. The core is rich in iron and the atmosphere is rich in oxygen, and between them is the entire range of pressures and temperatures on the planet.

"Interactions between oxygen and iron dictate Earth's formation, differentiation--or the separation of the core and mantle--and the evolution of our atmosphere, so naturally we were curious to probe how such reactions would change under the high-pressure conditions of the deep Earth," said Mao.

The research team--Qingyang Hu, Duck Young Kim, Wenge Yang, Liuxiang Yang, Yue Meng, Li Zhang, & Ho-Kwang Mao--put ordinary rust, or FeOOH, under about 900,000 times normal atmospheric pressure and at about 3200 degrees Fahrenheit and were able to synthesize a form of iron oxide, FeO2, that structurally resembles pyrite, also known as fool's gold. The reaction gave off hydrogen in the form of H2.

FeOOH is found in iron ore deposits that exist in bogs, so it could easily move into the deep Earth at plate tectonic boundaries, as could samples of ferric oxide, Fe2O3, which along with water will also form the pyrite-like iron oxide under deep lower mantle conditions.

Why does this interest the researchers? For one thing, this type of reaction could have started in Earth's infancy, and understanding it could inform theories of our own planet's evolution, as well as its current geochemistry.

Furthermore, the H2 released in this reaction would work its way upward, possibly reacting with other materials on its way. Meanwhile, the iron oxide would settle planet's depths and form reservoirs of oxygen there, particularly if one of these patches of iron oxide moved upward along the pressure gradient to the middle part of the mantle and separated into iron and O2.

"Pools of free oxygen under these conditions could create many reactions and chemical phases, which might be responsible for seismic and geochemical signatures of the deep Earth," Mao explained.

"Our experiments mimicking mantle conditions demonstrate that more research is needed on this pyrite-like phase of iron oxide." Hu added.

Read more at Science Daily

How El Niño impacts global temperatures

Wahyoe Hantoro in Liang Luar Cave, Flores.
Scientists have found past El Niño oscillations in the Pacific Ocean may have amplified global climate fluctuations for hundreds of years at a time.

The team uncovered century-scale patterns in Pacific rainfall and temperature, and linked them with global climate changes in the past 2000 years.

For example, northern hemisphere warming and droughts between the years 950 and 1250 corresponded to an El Niño-like state in the Pacific, which switched to a La Niña-like pattern during a cold period between 1350 and 1900.

The new data will help scientists build more accurate models of future climate, said member of the research team, Alena Kimbrough, from The Australian National University.

"Our work is a significant piece in the grand puzzle. The tropics are a complicated, yet incredibly important region to global climate and it's been great to untangle what's happening," said Ms Kimbrough, a PhD student at the ANU Research School of Earth Sciences.

"The current models struggle to reflect century-scale changes in the El Niño Southern Oscillation (ENSO).

"We've shown ENSO is an important part of the climate system that has influenced global temperatures and rainfall over the past millennium."

The team measured trace elements and stable isotopes in stalagmites from the Indonesian island of Flores to reconstruct ancient rainfall, and compared it with records from East Asia and the central-eastern equatorial Pacific.

The El Niño Southern Oscillation is an irregular variation in winds and sea surface temperatures over the tropical eastern Pacific Ocean. In one extreme it brings high temperatures and drought to eastern Australia and Indonesia, and the opposite extreme, known as La Niña, heavy rainfall and storms.

"In the past decade or so the rise in global temperature had a brief reprieve, the so-called warming hiatus, which can be partly attributed to a persistent La Niña pattern over that period," Ms Kimbrough said.

The new work found periods of predominantly El Niño-like patterns for several hundred years that alternate with La Niña patterns, impacting on global climate over the last 2000 years.

"Until we can model this lower-frequency behaviour in the tropical Pacific, one can only speculate on how the warming will play out over the next few decades," said lead author Dr Michael Griffiths from William Paterson University, in the United States.

Read more at Science Daily

Ancient ants leaving a modern trail

Map of historical land connectivity.
Past land connections, as well as current climate, are shown to be of primary importance in determining ant diversity patterns.

It is thought that ants evolved about 150 million years ago and have risen to dominance in the past 60 million years. They are now everywhere and while they are not always welcome on your kitchen counter, they are critical to ecosystems around the world for many roles, including seed dispersal and decomposition. There are a variety of factors that can impact diversity in geographically-clustered ant communities, but it can be difficult to decipher the most important biogeographic influences on these ant populations. Patricia Wepfer, Dr. Benoit Guénard (currently at the University of Hong Kong), and Prof. Evan Economo from the Biodiversity and Biocomplexity Unit at Okinawa Institute of Science and Technology Graduate University (OIST) unravelled the web of biogeographic components to find the influences that most significantly affect ant communities. They recently published their results in the Journal of Biogeography.

"I was interested in how different these communities could be across Asia," Patricia Wepfer, first author and OIST Ph.D. student said. "We wanted to know how a community [of ants] is composed in different places and why it is composed in that way."

The team assembled a large dataset of ant species occurrence records for 159 areas in Asia ranging from the Ryukyu Islands to Taiwan and coastal regions of South Korea. From this data, they determined which ants existed where and what factors may be affecting the communities.

They then analysed whether the climate -- temperature, rainfall -- and/or space -- geographical distance, water barriers -- made more of a difference to the composition of ant communities. The researchers also looked more closely to see whether historical land connections significantly affect ant communities. During the Last Glacial Maximum in the Pleistocene Epoch, approximately 26,000 years ago, many areas and islands in Asia were connected. As the land moved, the ocean began to cover these areas and create separate land masses. Surprisingly, ant population configurations of today are very much influenced by these past land connections that existed in the Pleistocene.

"Interestingly, the past land connections during the Last Glacial Maximum are more important in explaining the existing ant community patterns, than the way land is configured now," Wepfer said. "This may be due to the fact that historical land connections existed for a much longer time than the connections that we have today and ants take a long time to distribute."

While historical land connections are the most surprising factor in determining the make-up of a geographically-clustered ant community, ecologists also have to consider current and recognized influences, such as the temperature. From the data, the team determined that the temperature played the largest role in the differentiation between ant communities. With the advent of climate change, this may have many implications on ant ecosystems, as well as the ecosystems they work to sustain.

"Temperature is the dominant factor and plays a major role in shaping ant communities," Wepfer said. "Climate change will likely change these ant communities."

It is well-known in ecology that temperature is of the utmost importance in shaping species distributions, but it is important to keep in mind the spatial influence upon ant communities.

"In order to understand why species are where they are, we need to think about the current climate and land connections between areas," Economo said. "But also what the connections between areas were during the Last Glacial Maximum, which is when the sea levels were very low."

Read more at Science Daily

Jun 8, 2016

Names recommended for elements 115, 117 and 118

The International Union of Pure and Applied Chemistry (IUPAC) opened a public comment period Wednesday for the recommended names of elements 115, 117 and 118.

Lawrence Livermore National Laboratory and the Joint Institute for Nuclear Research in Dubna, Russia (JINR) were credited late last year for discovering elements 115 and 118. LLNL, JINR, Oak Ridge National Laboratory (ORNL), Vanderbilt University and the University of Nevada, Las Vegas were credited with the discovery of element 117.

Moscovium (Mc) is provisionally recommended for element 115 in recognition of the Moscow region and honoring the ancient Russian land that is home to JINR. Moscow is the capital of the region.

Tennessine (Ts) is proposed for element 117, recognizing the contribution of Tennessee research centers ORNL, Vanderbilt and the University of Tennessee to superheavy element research.

The provisional name for element 118 is Oganesson (Og) in recognition of the pioneering contributions of Yuri Oganessian to superheavy element research. Oganessian's vision and determination created this opportunity for the significant expansion of the periodic table and knowledge of superheavy nuclei.

The provisional names will undergo a statutory period for public review before the names and symbols can be finally approved by the IUPAC Council -- likely later this year.

"I'm proud of all of the hard work that this group has done over the years performing these experiments," said Dawn Shaughnessy," LLNL's principal investigator for the Heavy Element Group. "It's a huge accomplishment for the entire group that we are recognized for our efforts in accomplishing these highly difficult experiments and for the years of work it takes to successfully create a new chemical element."

LLNL teamed with JINR in 2004 to discover elements 113 and 115 (Japan was credited with the discovery of element 113). LLNL worked again with JINR in 2006 to discover element 118. The LLNL/JINR team then jointly worked with researchers from the Research Institute for Advanced Reactors (Dimitrovgrad), ORNL, Vanderbilt University and the University of Nevada, Las Vegas, to discover element 117 in 2010.

This discovery brings the total to five new elements reported by the Dubna-Livermore team (114, 115, 116, 117 and 118, the heaviest element to date).

The new elements and nuclei will complete the seventh row of the periodic table, and provides evidence for the long sought "island of stability" for superheavy elements. Two members of the team, JINR and LLNL, were previously credited with the discovery of elements 114 (flerovium) and 116 (livermorium).

The concept of the "island of stability" was originally proposed in the 1960s. It predicts increased stability for superheavy nuclei at higher neutron and proton numbers. The new nuclei produced in this research exhibit substantially increased lifetimes consistent with approaching the island.

Read more at Science Daily

Universe's first life might have been born on carbon planets

Our Earth consists of silicate rocks and an iron core with a thin veneer of water and life. But the first potentially habitable worlds to form might have been very different. New research suggests that planet formation in the early universe might have created carbon planets consisting of graphite, carbides, and diamond. Astronomers might find these diamond worlds by searching a rare class of stars.

"This work shows that even stars with a tiny fraction of the carbon in our solar system can host planets," says lead author and Harvard University graduate student Natalie Mashian.

"We have good reason to believe that alien life will be carbon-based, like life on Earth, so this also bodes well for the possibility of life in the early universe," she adds.

The primordial universe consisted mostly of hydrogen and helium, and lacked chemical elements like carbon and oxygen necessary for life as we know it. Only after the first stars exploded as supernovae and seeded the second generation did planet formation and life become possible.

Mashian and her PhD thesis advisor Avi Loeb (Harvard-Smithsonian Center for Astrophysics) examined a particular class of old stars known as carbon-enhanced metal-poor stars, or CEMP stars. These anemic stars contain only one hundred-thousandth as much iron as our Sun, meaning they formed before interstellar space had been widely seeded with heavy elements.

"These stars are fossils from the young universe," explains Loeb. "By studying them, we can look at how planets, and possibly life in the universe, got started."

Although lacking in iron and other heavy elements compared to our Sun, CEMP stars have more carbon than would be expected given their age. This relative abundance would influence planet formation as fluffy carbon dust grains clump together to form tar-black worlds.

From a distance, these carbon planets would be difficult to tell apart from more Earth-like worlds. Their masses and physical sizes would be similar. Astronomers would have to examine their atmospheres for signs of their true nature. Gases like carbon monoxide and methane would envelop these unusual worlds.

Read more at Science Daily

Epic Galactic 'Rainstorm' Feeds Monster Black Hole

It was always assumed that supermassive black holes consumed hot gas slow and steady -- but one black hole is about to binge-eat a massive cold gas dinner.

Supermassive black holes are the most massive objects in the universe and they are known to occupy the cores of most galaxies. They can "weigh in" at millions or even billions of times the mass of our sun, but it's not entirely clear how they came to be so huge.

But after staring deep in the core of the Abell 2597 galaxy cluster, around one billion light-years away, astronomers using the monster Atacama Large Millimeter/submillimeter Array (ALMA) in Chile had a surprise insight to the eating habits of one particular galaxy, wonderfully named "Abell 2597 Brightest Cluster Galaxy."

ALMA's key advantage is that it can detect the emissions emanating from some of the coldest molecular clouds in the universe. These clouds are key to the birth of stars and, in this case, possibly a key component of a supermassive black hole's diet. While observing this particular galaxy, ALMA detected cold and dense molecular clouds condense out of hot intergalactic gas in the galaxy cluster. Then, like an ultra-violent rain storm, the cold gas down-poured onto the black hole.

"This very, very hot gas can quickly cool, condense, and precipitate in much the same way that warm, humid air in Earth's atmosphere can spawn rain clouds and precipitation," said astronomer Grant Tremblay, of Yale University and lead author on a new paper to be published in the journal Nature on June 9. "The newly condensed clouds then rain in on the galaxy, fueling star formation and feeding its supermassive black hole.

"Although it has been a major theoretical prediction in recent years, this is one of the first unambiguous pieces of observational evidence for a chaotic, cold rain feeding a supermassive black hole," he added. "It's exciting to think we might actually be observing this galaxy-spanning rainstorm feeding a black hole whose mass is about 300 million times that of the sun."

The cosmic weather report, as illustrated in this artist's concept, calls for condensing clouds of cold molecular gas around the Abell 2597 Brightest Cluster Galaxy.
Tremblay's team have detected three separate clumps of material, each with a mass of around a million solar masses, measuring tens of light-years across. They are currently speeding toward the black hole at nearly a million kilometers per hour. These particular clouds could only be detected as they are passing in front of the stars in the core of the galaxies, so ALMA was able to gauge their mass and speed by studying the clouds' shadows.

Follow-up observations by the NSF's Very Long Baseline Array have shown that these clouds are very close to the black hole at a distance of only 300 light-years. If these clouds were a hurricane, it would be about to make landfall.

Read more at Discovery News

Mammals Thrived Long Before Dinos Died

The prevailing theory that mammals only flourished after an asteroid strike wiped out the dinosaurs 66 million years ago is doubly wrong, according to a study published Wednesday.

Our warm-blooded predecessors thrived and spread over millions of years even as Tyrannosaurus and other flesh-ripping monsters lorded over the planet, researchers reported.

Moreover, these mammals took a big hit when the asteroid slammed into Earth, creating a hemispheric firestorm followed by a prolonged, bone-chilling drop in global temperatures.

"The traditional view is that mammals were suppressed during the 'age of dinosaurs'," and thus held in check, said co-author Elis Newham, a doctoral student in evolutionary biology at the University of Chicago.

"However, our findings were that therian mammals -- the ancestors of most modern mammals -- were already diversifying considerably before the Cretaceous-Tertiary extinction event," also known as the K-Pg boundary.

The researchers pulled together dozens of studies that challenged and chipped away at the old theory.

But key to the new conclusion, they said, was teeth.

An analysis of hundreds of molars from mammals alive during the 20 million years before the K-Pg boundary revealed a huge variety of shapes -- a telltale sign of varied diets and species diversity.

The scientists were surprised to find a sharp decline in the number of mammals after the asteroid crash.

"I didn't expect to see any sort of drop," said lead author David Grossnickle, also of the University of Chicago.

"It didn't match the traditional view that after the extinction, mammals hit the ground running."

Once again, teeth told a story, this time revealing which mammals made it across the K-Pg boundary, and which did not.

Those with molars indicating a specialised diet -- only bugs or only plants, for example -- were less likely to weather the disaster than those with all-purpose chompers ready to eat whatever was available.

The findings, published in Proceedings of the Royal Society B, may hold a lesson for today's world, Grossnickle said.

Scientists say Earth is experiencing another mass extinction event, driven mainly by climate change -- only the sixth in the last half billion years, he pointed out.

"The types of survivors that made it 66 million years ago, mostly generalists, might be indicative of what will survive in the next hundred years, or the next thousand," Grossnickle said in a statement.

Read more at Discovery News

700,000-Year-Old Tiny Humans Found at Hobbit Homeland

Reconstruction of Homo floresiensis by Atelier Elisabeth Daynes.
Remains of at least three tiny humans dating to 700,000 years ago have been found on the Indonesian island of Flores, which was the homeland of Homo floresiensis, aka "Hobbit Humans," according to two new papers in the journal Nature.

The newly found early humans, represented by a partial right jaw and some isolated teeth, predate the Hobbits by more than half a million years, the papers report. Their presence on the island suggests that the small individuals were part of a population that later gave rise to the Hobbits, whose fossils were previously discovered at Flores' Liang Bua cave.

"We cannot be sure about their actual body size because we only have the mandible and teeth," Yousuke Kaifu, co-author of the first paper, told Discovery News, "but their sizes suggest that these 700,000-year-old hominins (early members of the genus Homo) were as small as Homo floresiensis from Liang Bua."

The Hobbits were about 3.3 feet tall.

Partial right jaw excavated on the island of Flores, Indonesia.
700,000-year-old tooth from a member of the genus Homo and excavated from the island of Flores, Indonesia.
Kaifu, an anthropologist at the National Museum of Nature and Science in Japan, along with lead author of the first paper Gerrit van den Bergh and their colleagues, analyzed the new remains. They were excavated from layers of sedimentary rock at a site called Mata Menge, located approximately 43.5 miles away from Liang Bua. The researchers believe that the fossils came from early Homo floresiensis and belonged to at least one adult and two children.

When the Hobbit remains were first found in 2003, many scientists were completely baffled by the population's diminutive size. Some even thought that the individuals were members of our species who were pathologically dwarfed or diseased.

Van den Bergh, however, said that the latest discovery "quashes once and for all any doubters that believe Homo floresiensis was merely a sick modern human."

The second paper, with research led by Adam Brumm of Griffith University and the University of Wollongong, describes the geology of Mata Menge and confirms that the Hobbit predecessors lived at least 700,000 years ago. It said that stone tools were also found at Flores and date to approximately 700,000 to 1 million years ago.

Taken together, all of the finds suggest that a population of small individuals lived perhaps continuously as a lineage on the island from about a million years ago to at least around 38,000–60,000 years ago. As for where they came from before settling on Flores, Kaifu suspects that "a large-bodied Homo erectus population got there and dwarfed on the island."

A model of the face of an adult female Homo erectus.
He added, "Rather than claiming that such extreme body and brain size dwarfism cannot occur (on a widespread scale), we now have accepted that that happened and can shift to the next question as to why that happened and on what mechanism."

Aida Gómez-Robles, a scientist at George Washington University specializing in human evolution, explained that one theory about the Hobbits says they shrunk in size by a process called island dwarfing. This refers to an extreme reduction in size due to the absence of predators and to resource scarcity that is typical of island ecosystems.

When the Hobbit remains were first found, the researchers also discovered evidence for a pygmy elephant, suggesting that a pachyderm also underwent island dwarfing at Flores.

Gómez-Robles told Discovery News that the two new papers are important because "they demonstrate that the origin of Homo floresiensis is very old, which confirms that this is a totally valid species with old evolutionary roots."

Read more at Discovery News

Jun 7, 2016

Computer simulations shed light on the Milky Way's missing red giants

New computer simulations from the Georgia Institute of Technology provide a conclusive test for a hypothesis of why the center of the Milky Way appears to be filled with young stars but has very few old ones. According to the theory, the remnants of older, red giant stars are still there -- they just aren't bright enough to be detected with telescopes.

The Georgia Tech simulations investigate the possibility that these red giants were dimmed after they were stripped of 10s of percent of their mass millions of years ago during repeated collisions with an accretion disk at the galactic center. The very existence of the young stars, seen in astronomical observations today, is an indication that such a gaseous accretion disk was present in the galactic center because the young stars are thought to have formed from it as recently as a few million years ago.

The study is published in the June edition of The Astrophysical Journal. It is the first to run computer simulations on the theory, which was introduced in 2014.

Astrophysicists in Georgia Tech's College of Sciences created models of red giants similar to those that are supposedly missing from the galactic center -- stars that are more than a billion years old and 10s of times larger in size than the Sun. They put them through a computerized version of a wind tunnel to simulate collisions with the gaseous disk that once occupied much of the space within .5 parsecs of the galactic center. They varied orbital velocities and the disk's density to find the conditions required to cause significant damage to the red giant stars.

"Red giants could have lost a significant portion of their mass only if the disk was very massive and dense," said Tamara Bogdanovic, the Georgia Tech assistant professor who co-led the study. "So dense, that gravity would have already fragmented the disk on its own, helping to form massive clumps that became the building blocks of a new generation of stars."

The simulations suggest that each of the red giant stars orbited its way into and through the disk as many as dozens of times, sometimes taking as long as days to weeks to complete a single pass-through. Mass was stripped away with each collision as the star blistered the fragmenting disk's surface.

According to former Georgia Tech undergraduate student Thomas Forrest Kieffer, the first author on the paper, it's a process that would have taken place 4 to 8 million years ago, which is the same age as the young stars seen in the center of the Milky Way today.

"The only way for this scenario to take place within that relatively short time frame," Kieffer said, "was if, back then, the disk that fragmented had a much larger mass than all the young stars that eventually formed from it -- at least 100 to 1,000 times more mass."

The impacts also likely lowered the kinetic energy of the red giant stars by at least 20 to 30 percent, shrinking their orbits and pulling them closer to the Milky Way's black hole. At the same time, the collisions may have torqued the surface and spun up the red giants, which are otherwise known to rotate relatively slowly in isolation.

Read more at Science Daily

Origin of extraordinary supernovae

Using data obtained through the Optical and Infrared Synergetic Telescopes for Education and Research (OISTER) in Japan, Masayuki Yamanaka, a Taro Hirao Foundation Researcher at Konan University, demonstrated that the origin of extraordinary supernovae can be explained by the 'accretion scenario.' The researchers discovered an anomalously strong infrared emission from 'the extraordinary supernova' SN 2012dn, which has never been observed in other Type Ia supernovae to date. Through detailed analysis, the researchers concluded that the infrared emission comes from the material ejected from the progenitor system.

Astronomers using the OISTER telescope consortium in Japan have uncovered new information about the origin of 'extraordinary supernovae' explosions, which are brighter than normal ones. This new information will help improve measurements of the Universe's expansion, and of the Dark Energy which controls the final fate of the cosmos.

Type Ia ("One-A") supernovae are a type of exploding star which are used as references when studying the Universe. What makes these supernovae useful is that the physics governing their evolution ensures that they all change from a stable state to an explosion at almost exactly the same point in their evolution. This means that the brightness of a Type Ia supernova explosion is consistent from one star to the next. By using the known brightness of these supernovae, astronomers can use them to calibrate observations. For example, in the late 1990's, the accelerating expansion of the Universe was discovered by using the properties of Type Ia supernovae. Drs. Perlmutter, Riess, and Schmidt were awarded the Novel Prize in Physics in 2011 for this work.

But it turns out there's a problem with this method. In addition to normal Type Ia supernovae, astronomers have discovered 'extraordinary supernovae' which are much brighter than they should be. These 'extraordinary supernovae' may be contaminating the samples used for cosmological research, thereby skewing the calibration. To correctly measure the expansion of the Universe and understand the Dark Energy driving the expansion, it is important to determine the origins of both typical supernovae and 'extraordinary supernovae' so that the latter can be more accurately excluded from the sample.

Despite three decades of debate, astronomers still haven't agreed on the origin of these supernovae. There are two popular scenarios, 'accretion' or 'merger', as the path to the supernova explosion. Both scenarios consider a 'binary system,' i.e., two stars orbiting around each other. The 'accretion' scenario uses binary systems composed of one white dwarf and one normal star, and the 'merger' scenario uses binary systems formed by two white dwarfs.

When the 'extraordinary supernovae' candidate SN 2012dn was spotted, Masayuki Yamanaka, a Taro Hirao Foundation Researcher at Konan University, and his colleagues observed it using 11 telescopes in Japan through OISTER (Optical and Infrared Synergetic Telescopes for Education and Research). The observations continued until 150 days after the supernova was first observed. As a result of this observing campaign, they discovered an anomalously strong infrared emission for this object which cannot be seen in typical supernovae. The groups performed detailed analysis of the infrared emission, and concluded that material ejected recently from the progenitor system is responsible for this emission.

Read more at Science Daily

Great Pyramid of Giza Gets High-Tech Scan

For the past 23 years researchers have been trying to unlock the mysteries of the Great Pyramid in Giza using tomb-raiding robots. Now scientists have turned to subatomic particles known as muons to scan the 4,500-year-old pharaonic mausoleum. The aim is to detect voids that might point to hidden chambers and tunnels.

The full scan of the iconic monument is one of several ambitious steps of ScanPyramids, a project carried out by a team from Cairo University's Faculty of Engineering and the Paris-based non-profit organization Heritage, Innovation and Preservation (Hip Institute) under the authority of the Egyptian Ministry of Antiquities.

In April the team was able to reveal for the first time the internal structure of the Bent pyramid at Dahshur, using cosmic particles.

In a statement released on Tuesday, the ScanPyramids team detailed three non-invasive techniques employed at Giza. The results of the survey will be shared with several committees representing different scientific disciplines. One of them will gather a number of Egyptologists led by the former minister of Antiquities Zahi Hawass.

"Our team is trying to get evidence from the field that some voids exists. Then it will be the role of historians, Egyptologists, architects, to tell why those voids are there," Mehdi Tayoubi, co-director of the ScanPyramids mission, told Discovery News.

Built for the pharaoh Cheops, also known as Khufu, the Great Pyramid is the last remaining wonder of the ancient world.

The monument is the largest of a family of three pyramids on the Giza plateau, on the outskirts of Cairo, and has long been rumored to have hidden passageways leading to secret chambers.

Archaeologists have long puzzled over the purpose of four narrow shafts deep inside the pyramid since they were first discovered in 1872.

Two shafts extend from the upper or "King's Chamber" exit into open air. But the lower two, one on the south side and one on the north side in the so-called "Queen's Chamber" disappear within the structures, deepening the pyramid mystery.

Widely believed to be ritual passageways for the dead pharaoh's soul to reach the afterlife, these 8-inch-square shafts remained unexplored until 1993, when German engineer Rudolf Gantenbrink sent a robot through the southern shaft.

After a steady climb from the heart of the pyramid, the robot came to a stop in front of a mysterious limestone slab adorned with two copper pins.

In 2002, Hawass explored the southern shaft on live television. As the world held its breath, a robot pushed a camera through a hole drilled in the copper pinned door — only to reveal what appeared to be another door.

The following day, Hawass sent the robot through the northern shaft.

After crawling for 213 feet and navigating several sharp bends, the robot came to an abrupt halt in front of another limestone slab.

As with the Gantenbrink door, the stone was adorned with two copper pins.

In the attempt to finally solve the mystery, Hawass established in 2011 the Djedi project, a joint international-Egyptian mission (Leeds University, Dassault Systèmes). The project began with the exploration of the southern shaft, which ends at the so called "Gantenbrink's door."

The robot was able to climb inside the walls of the shaft while carrying a bendy camera, small enough to fit through a small hole in a stone door at the end of the tunnel.

This gave researchers a clear view into the chamber beyond. It was at that time that the micro snake camera sent back images of 4,500-year-old markings believed to be engineering numbers.

The project was then halted following the Egypt revolution.

"I dedicated my whole life to study the secrets of the Great Pyramid. My goal is to finally find out what's behind these secret doors," Zahi Hawass told Discovery News in a past interview.

He will now have another chance with the ScanPyramids's innovative and non destructive technologies.

Tayoubi explained to Discovery News that the first of the three employed techniques relies on muons. These cosmic particles permanently and naturally rain on Earth and are able to penetrate any material very deeply.

Overall, 80 emulsion films made by Nagoya University, Japan, have been placed inside the Great Pyramid at different places, in the Queen's chamber, Queen'schamber niche, and lower chamber.

"They will be exposed to the muons' natural flow for 40 days," Tayoubi said.

The films will then be analyzed to generate muon radiographies images, potentially revealing hidden chambers in the pyramid.

"In case a void is detected, the images generated from the emulsion film analysis show a contrast difference," Tayoubi said.

"It is a very accurate but very long process," he added.

Read more at Discovery News

Bones From 6,000-Year-Old Massacre Found in France

Archaeologists said Tuesday they had discovered the remains of victims from a 6,000-year-old massacre in Alsace in eastern France that was likely carried out by "furious ritualized warriors".

The corpses of 10 people were found outside Strasbourg in one of 300 ancient "silos" used to store grain and other food, a team from France's National Institute for Preventive Archaeological Research (Inrap) told reporters.

The Neolithic group appeared to have died violent deaths, with multiple injuries to their legs, hands and skulls.

 The way in which the bodies were piled on top of each other suggested they had been killed together and dumped in the silo.

"They were very brutally executed and received violent blows, almost certainly from a stone axe," said Philippe Lefranc, an Inrap specialist on the period.

 The skeletons of five adults and one adolescent were found, as well as four arms from different individuals.

The arms were likely "war trophies" like those found at a nearby burial site of Bergheim in 2012, said Lefranc.

He said the mutilations indicated a society of "furious ritualised warriors", while the silos were stored within a defence wall that pointed towards "a troubled time, a period of insecurity."

Read more at Discovery News