Dec 23, 2016
Many scientists have figured out how to capture those electrons in microbial fuel cells and turn them into a power source. But Seokheun "Sean" Choi, assistant professor and director of the Bioelectronics & Microsystems Lab the State University of New York, Binghamton, has figured out how to do it using paper.
His foldable, paper-based battery is a bacteria-powered fuel cell that could be used to run small biosensors. Because it's made from paper, the device is cheap and disposable. Because it runs on microbes, it can generate energy wherever and whenever it's needed.
"Theoretically, the microorganisms are everywhere. I thought that the bacteria-based battery could be activated even in the most resource-limited settings," Choi told Seeker.
This might mean using it in disaster areas, on the battlefield or in clinics that serve impoverished communities.
Fundamentally, Choi's battery has the two main components of all batteries: an anode, considered the negative end, and a cathode, considered the positive end. The anode is typically the source of the electrons, which flow to the cathode to create a current.
With this battery, Choi created an anode on one side of paper that's made of a tiny amount of bacteria-laden water housed in a reservoir formed in a conductive polymer. On the other side of the paper is the cathode, a ribbon of silver nitrate underneath a thin layer of wax.
By folding the paper so that the two sides come into contact, electrons from the microbes flow toward the cathode to create an electric current. Folding the battery in different shapes varies the electrical output. For example, by crimping it accordion-style so that six rows of six fuel cells are touching, the battery produces 44.85 microwatts at 105.89 microamps.
Choi acknowledges that this is a very small amount of power. In the early days, when he first considered making paper electronics, he was skeptical they'd have any use. But then he realized that biosensors, like those that detect pathogens or monitor the blood sugar levels, didn't need much power to begin with. He also liked the idea of tapping a ubiquitous source of energy.
"Now, this work uses wastewater, but the devices can be workable with any liquid like body fluids, such as blood, sweat, urine, or saliva," he said.
This is not Choi's first paper battery. Earlier this year, his team introduced a design that folded up into a Ninja star-shaped frame.
Read more at Discovery News
The Koh-i-Noor ("Mountain of Light"), now part of the British Crown Jewels, has witnessed the birth and the fall of empires across the Indian subcontinent, and remains the subject of a bitter ownership battle between Britain and India.
"It is an unbelievably violent story... Almost everyone who owns the diamond or touches it comes to a horribly sticky end," says British historian William Dalrymple, who co-authored "Kohinoor: The Story of the World's Most Infamous Diamond" with journalist Anita Anand.
"We get poisonings, bludgeonings, someone gets their head beaten with bricks, lots of torture, one person blinded by a hot needle. There is a rich variety of horrors in this book," Dalrymple tells AFP in an interview.
In one particularly gruesome incident the book relates, molten lead is poured into the crown of a Persian prince to make him reveal the location of the diamond.
Today the diamond, which historians say was probably first discovered in India during the reign of the Mughal dynasty, is on public display in the Tower of London, part of the crown of the late Queen Mother.
The first record of the Koh-i-Noor dates back to around 1750, following Persian ruler Nader Shah's invasion of the Mughal capital Delhi. Shah plundered the city, taking treasures such as the mythical Peacock Throne, embellished with precious stones including the Koh-i-Noor.
"The Peacock Throne was the most lavish piece of furniture ever made. It cost four times the cost of the Taj Mahal and had all the better gems gathered by the Mughals from across India over generations," Dalrymple says.
The diamond itself was not particularly renowned at the time — the Mughals preferred colored stones such as rubies to clear gems. Ironically given the diplomatic headaches it has since caused, it only won fame after it was acquired by the British.
"People only know about the Koh-i-Noor because the British made so much fuss of it," says Dalrymple.
India has tried in vain to get the stone back since winning independence in 1947, and the subject is frequently brought up when officials from the two countries meet. Iran, Pakistan and even the Afghan Taliban have also claimed the Koh-i-Noor in the past, making it a political hot potato for the British government.
Over the course of the century that followed the Mughals' downfall, the Koh-i-Noor was used variously as a paperweight by a Muslim religious scholar and affixed to a glittering armband worn by a Sikh king.
It only passed into British hands in the middle of the nineteenth century, when Britain gained control of the Sikh empire of Punjab, now split between Pakistan and India.
Sikh king Ranjit Singh had taken it from an Afghan ruler who had sought sanctuary in India and after he died in 1839 war broke out between the Sikhs and the British.
Singh's 10-year-old heir handed over the diamond to the British as part of the peace treaty that ended the war and the gem was subsequently displayed at the 1851 Great Exhibition in London — acquiring immediate celebrity status.
"It became, for the Victorians, a symbol of the conquest of India, just as today, for post-colonial Indians, it is a symbol of the colonial looting of India," Dalrymple says.
Read more at Discovery News
But with the recent discovery of a small rocky exoplanet in orbit around Proxima, this new finding will boost hopes that this little world may be habitable for life as we know it.
Proxima Centauri is located around 4.25 light-years away making it the nearest star to Earth beyond our sun. The star's planet, called Proxima b, is approximately the same mass as Earth and orbits within the star's "habitable zone" — the region surrounding a star that's neither too hot or too cold for liquid water to exist on a planetary surface. Finding any planet within a star's habitable zone — regardless of the star's size or luminosity — will always be exciting as, if there is liquid water there, life could be possible. And discovering a (potentially) habitable world on our galactic doorstep is an incredible stroke of luck.
Though we know that Proxima b is there, we can only guess at its composition and have no clue whether or not it possesses any water. But new evidence suggesting Proxima Centauri is indeed a distant sibling of the Alpha Centauri could help us find out.
Proxima Centauri was only discovered a century ago and, since then, astronomers have been trying to understand its motion in the sky, a task that becomes very complicated when considering how dim it is. Red dwarfs are many times smaller and produce only a fraction of the light of our sun. But using the High Accuracy Radial velocity Planet Searcher (HARPS) instrument at the ESO's La Silla Observatory in Chile, astronomers have, for the first time, gained precision measurements of the dim star's radial velocity, a key metric if we are to understand if it is in any way related to Alpha Centauri.
The HARPS instrument is extremely sensitive to the wobble of stars as small exoplanets orbit around them, gravitationally tugging at them. Indeed, it was the HARPS instrument that discovered the tiny wobble of Proxima Centauri, revealing the presence of Proxima b. But this time, HARPS was able to deduce the velocity at which the tiny star is moving away from us and compared it with the radial velocity of Alpha Centauri. Both radial velocities closely match, which means that, in all likelihood, Proxima Centauri has a wide orbit around Alpha Centauri. They are therefore, probably, gravitationally bound.
Though this is a significant find — indeed, the question of whether or not all three stars are in orbit around one another has been vexing astronomers since Proxima Centauri was first spotted — it could reveal an interesting tidbit about the nature of Proxima b itself.
If Proxima Centauri and Alpha Centauri are gravitationally bound, this gives us a clue that the group formed from the same star-forming nebula billions of years ago. They are all therefore the same age. Over time, the trio's orbits evolved and Proxima Centauri for some reason was thrown away from the Alpha Centauri binary. In research to be published in the journal Astronomy & Astrophysics, the researchers speculate that before Proxima Centauri was ejected and sent on the lonely orbit it's in today, a planet formed far from the star and then migrated to a lower orbit. As it occupied such a distant (and cold) orbit, it would have likely been an icy world and that ice could have been water. And now Proxima b is orbiting in a very habitable location for liquid water to exist on its surface, then perhaps — just perhaps — it possesses water to this day.
Read more at Discovery News
The scene, painted in reddish-brown ochre, was found on the ceiling of a small cavity in the Egyptian Sahara desert, during an expedition to sites between the Nile valley and the Gilf Kebir Plateau.
"It's a very evocative scene which indeed resembles the Christmas nativity. But it predates it by some 3,000 years," geologist Marco Morelli, director of the Museum of Planetary Sciences in Prato, near Florence, Italy, told Seeker.
Morelli found the cave drawing in 2005, but only now his team has decided to reveal the amazing find.
"The discovery has several implications as it raises new questions on the iconography of one of the more powerful Christian symbols," Morelli said.
The scene features a man, a woman missing the head because of a painting detachment, and a baby.
"It could have been interpreted as a normal depiction of a family, with the baby between the parents, but other details make this drawing unique," Morelli said.
He noted the newborn is drawn slightly above, as if raising to the sky. Such position, with the baby not yet between the parents, would have meant a birth or a pregnancy.
"As death was associated to Earth in contemporary rock art from the same area, it is likely that birth was linked to the sky," Morelli said.
The scene becomes more symbolically complex if the other figures, two animals and a small circular feature, are taken into consideration.
Read more at Discovery News
Dec 22, 2016
|The painted lady butterfly (Vanessa cardui) is a major component of the large day-flying insect migrants studied by radar in the new study.|
For the first time, scientists have measured the movements of high-flying insects in the skies over southern England -- and found that about 3.5 trillion migrate over the region every year.
This movement of 3,200 tons of biomass, captured by University of Exeter and Rothamsted Research using specialised radar techniques, is more than seven times the mass of the 30 million songbirds which depart the UK for Africa each autumn.
(It is also the equivalent of about 20,000 flying reindeer.)
Dr Jason Chapman, of the Centre for Ecology and Conservation at the University of Exeter's Penryn Campus in Cornwall, said: "Insect bodies are rich in nutrients and the importance of these movements is underappreciated.
"If the densities observed over southern UK are extrapolated to the airspace above all continental landmasses, high-altitude insect migration represents the most important annual animal movement in ecosystems on land, comparable to the most significant oceanic migrations."
Although the origin and destination of each insect was not recorded, evidence from previous research suggests many will have been travelling to and from the UK over the English Channel and North Sea.
The scientists recorded movement above radar sites in southern England and found large seasonal differences, with mass migrations of insects generally going northwards in spring and southwards in autumn.
Until now, radar studies have measured migrations of relatively few nocturnal species of agricultural pests, and no study previously examined the vast numbers of daytime migrants.
The study found seasonal variations from year to year, but overall the net northward spring movements of larger insects were almost exactly cancelled out by net southward movements in autumn over the 10-year research period.
Dr Gao Hu, a visiting scholar with Dr Chapman from Nanjing Agricultural University, China, led the analyses of the radar data.
He said: "Many of the insects we studied provide important ecological services which are essential for maintaining healthy ecosystems, such as pollination, predation of crop pests and providing food for insectivorous birds and bats."
Co-author Dr Ka S (Jason) Lim, of the Radar Entomology Unit of the AgroEcology Department at Rothamsted Research, said migratory insects can serve as indicators of global environmental condition.
"Animal migration, especially in insects, is a very complex behaviour which takes millions of year to evolve and is very sensitive to climatic condition," he said.
Read more at Science Daily
|If countries abide by the Paris Agreement global warming target of 1.5 degrees Celsius, potential fish catches could increase by six million metric tons per year, according to a new study published in Science.|
The researchers also found that some oceans are more sensitive to changes in temperature and will have substantially larger gains from achieving the Paris Agreement.
"The benefits for vulnerable tropical areas is a strong reason why 1.5 C is an important target to meet," said lead author William Cheung, director of science at the Nippon Foundation-Nereus Program and associate professor at UBC's Institute for the Oceans and Fisheries.
"Countries in these sensitive regions are highly dependent on fisheries for food and livelihood, but all countries will be impacted as the seafood supply chain is now highly globalized. Everyone would benefit from meeting the Paris Agreement."
The authors compared the Paris Agreement 1.5 C warming scenario to the currently pledged 3.5 C by using computer models to simulate changes in global fisheries and quantify losses or gains. They found that for every degree Celsius decrease in global warming, potential fish catches could increase by more than three metric million tons per year. Previous UBC research shows that today's global fish catch is roughly 109 million metric tons.
"Changes in ocean conditions that affect fish stocks, such as temperature and oxygen concentration, are strongly related to atmospheric warming and carbon emissions," said author Thomas Frölicher, principal investigator at the Nippon Foundation-Nereus Program and senior scientist at ETH Zürich. "For every metric ton of carbon dioxide emitted into the atmosphere, the maximum catch potential decreases by a significant amount."
Climate change is expected to force fish to migrate towards cooler waters. The amount and species of fish caught in different parts of the world will impact local fishers and make fisheries management more difficult.
The findings suggest that the Indo-Pacific area would see a 40 per cent increase in fisheries catches at 1.5 C warming versus 3.5 C. Meanwhile the Arctic region would have a greater influx of fish under the 3.5 C scenario but would also lose more sea ice and face pressure to expand fisheries.
The authors hope these results will provide further incentives for countries and the private sector to substantially increase their commitments and actions to reduce greenhouse gas emissions.
Read more at Science Daily
|These are stem cells becoming fat cells. Using the ultrasound technique, we can start exploring why fat cells put on fat and whether we can make the cells 'diet'.|
The new nanoscale ultrasound technique uses shorter-than-optical wavelengths of sound and could even rival the optical super-resolution techniques which won the 2014 Nobel Prize for Chemistry.
This new kind of sub-optical phonon (sound) imaging provides invaluable information about the structure, mechanical properties and behaviour of individual living cells at a scale not achieved before.
Researchers from the Optics and Photonics group in the Faculty of Engineering, University of Nottingham, are behind the discovery, which is published in the paper 'High resolution 3D imaging of living cells with sub-optical wavelength phonons' in the journal, Scientific Reports.
"People are most familiar with ultrasound as a way of looking inside the body -- in the simplest terms we've engineered it to the point where it can look inside an individual cell. Nottingham is currently the only place in the world with this capability," said Professor Matt Clark, who contributed to the study.
In conventional optical microscopy, which uses light (photons), the size of the smallest object you can see (or the resolution) is limited by the wavelength.
For biological specimens, the wavelength cannot go smaller than that of blue light because the energy carried on photons of light in the ultraviolet (and shorter wavelengths) is so high it can destroy the bonds that hold biological molecules together damaging the cells.
Optical super-resolution imaging also has distinct limitations in biological studies. This is because the fluorescent dyes it uses are often toxic and it requires huge amounts of light and time to observe and reconstruct an image which is damaging to cells.
Unlike light, sound does not have a high-energy payload. This has enabled the Nottingham researchers to use smaller wavelengths and see smaller things and get to higher resolutions without damaging the cell biology.
Read more at Science Daily
Proving that our planet contains unexplored places with never-before-recorded plants and animals (with their own set of evolving viruses), the scientists made their finds over five continents and three oceans, ventured into vast deserts, plunged beneath the sea, and scoured thick rainforests and towering mountain ranges. Their results help advance the Academy's mission to explore, explain, and sustain life on Earth.
"Biodiversity scientists estimate that we have discovered less than 10% of the species on our planet," says Dr. Shannon Bennett, Academy Chief of Science. "Academy scientists tirelessly explore the lesser-known regions of Earth -- not only to discover new species, but also to uncover the importance of these species to the health of our natural systems. Each of these species, known and as-yet-unknown, is a wonder unto itself but may also hold the key to ground-breaking innovations in science, technology, or society. Species live together in rich networks that thrive on complexity whether we can see it or not. Even the tiniest organism," she adds, "can be beautiful and important."
Below are a few highlights among the 133 species described by the Academy in 2016.
Flashy "twilight zone" groppo -- deepest fish discovered by human hands
One pink-and-yellow fish has earned its spot in deep reef history. Grammatonotus brianne -- an eye-popping species of groppo -- is the deepest new fish discovery ever made by human hands. The discovery was captured on film at 487 feet beneath the ocean's surface.
Academy scientists are currently diving to twilight zone reefs around the world. In these narrow bands of deep reefs, animals live in partial darkness, well beyond recreational diving limits yet above the deep trenches patrolled by submarines and ROVs. Reaching extreme depths requires Academy divers and their collaborators to push the boundaries of both technology and the human body, using closed-circuit "rebreathers" that extend the amount of time they can spend underwater.
The new groppo is one of several new species discoveries made during an Academy expedition (along with research partners from Hawaii's Bishop Museum) to the Philippines in 2014 -- part of an ongoing, multi-year exploration of the Coral Triangle's biological treasures from the shallows to deep mesophotic "twilight zone" reefs 200 to 500 feet beneath the ocean surface.
Deep-diving Academy ichthyologist Dr. Luiz Rocha and Bishop Museum research associate Brian Greene spotted the neon groppo (later named G. brianne for Greene's wife) during a murky, cold dive in the Philippine Verde Island Passage, a region known as the "center of the center" of Earth's marine biodiversity.
"This groppo is the most beautiful fish I've ever seen," says Rocha, a co-leader of the Academy's monumental push to explore, explain, and sustain coral reefs around the world. "But beyond its looks, it's a reminder that we know very little about the mysterious half-lit reefs we call the twilight zone. We need to understand the life inside these largely-unexplored deeper reefs because they may help us understand how the oceans respond to great change."
G. brianne joins 24 new species of fishes -- from camouflaging gobies to lanternsharks of the Indian Ocean -- described by Academy scientists in 2016 alone.
43 new ants (and a crowd of blood-sucking "Draculas")
Dr. Brian Fisher, Academy curator of entomology and real-life "Ant Man," recently added a whopping 43 new species to the tree of life. Fisher is a fierce advocate for the importance of small animals that support all terrestrial communities, and has devoted his life to the study of ants and biodiversity. Since 1996, he has conducted fieldwork in Madagascar -- where only 10% of natural habitat remains -- to explore regional biodiversity and generate data to drive conservation priorities in the country.
"Our work in Madagascar focuses on determining which ants live where as we develop new field guides as tools for diagnosing and understanding conservation problems," Fisher says. "It's not just about generating data -- we are trying to create a culture of interest in the natural world, from the smallest ant to the tallest tree."
Several of this year's finds belong to a group called Stigmatomma -- "Dracula ants" that build tiny, few-chambered colonies (generally no larger than a dime) beneath the soil. In a bizarre but fascinating means of distributing nutrients throughout the colony, ants from this group are known to wound their colonies' babies before drinking their blood -- a substance called "hemolymph" in insects. An elongated jaw with two large pincers also allows the ants to grasp prey mostly comprised of centipedes, but also beetle larvae.
"Because these ants are so rarely collected, finding them is like uncovering buried treasure," says Flavia Esteves, a postdoctoral researcher at the Academy who has joined Fisher in the field since 2010. Most Stigmatomma species spend the entirety of their lives beneath the soil or inside rotten logs. Esteves cuts through Madagascar's clay-like soil with a machete, and then uses a pocket knife -- and finally, forceps -- to carefully expose the ants.
"In an island like Madagascar where human activities are destroying sensitive habitats, understanding specialized species such as Stigmatomma is even more important. We fear that the unique environmental niche they occupy will go unfilled once these ants are gone," says Esteves. "We still have so much to learn from these specialized soil dwellers," adds Fisher.
Fisher recently returned from a nine-month expedition to Mozambique, accompanied by Esteves, as part of a Fulbright Scholar Grant to study ants and climate. His work in Madagascar (including founding the country's first and only biodiversity research center) and Mozambique continue to provide conservation partners with a wealth of new biodiversity data and monitoring aids to inform future land-use planning.
A gray-haired "grandfather" bee fly
All around us, insects flit, hover, and buzz about, but one family -- the bee flies (Bombyliidae sp.) -- may cause passersby to look twice. The nearly 5,000 species that make up this fly group imitate a wide range of relatives, from delicate honey bees to menacing wasps and spiders. "Don't be deceived by stripes or fuzzy adornments," says fly-expert Dr. Michelle Trautwein, Academy curator of entomology: insects from this group are all flies. A new species from Madagascar was recently discovered as part of a collaborative project between the Academy and the Schlinger Foundation to document the country's diversity of insects and their close relatives.
Named Thevenetimyia spinosavus (which translates to "thorny grandfather"), this gray-haired bee fly was discovered by Natalia Maass, who worked with Trautwein for two summers as an undergraduate intern. While examining specimens under the microscope, Maass noticed one quite unlike the rest.
"He was longer and more slender than other bee flies, with big spikes on his thorax and longer, gray bristly hairs," says Trautwein, describing why Natalia granted it its grandparent moniker. What's more, this stubbled bee fly was completely isolated from any other species within the same relative group. Similar species of bee fly are found in Northern Africa and North America -- both a long way from Madagascar -- meaning this "thorny grandfather" is part of a group with an incredibly wide distribution.
No matter where they're found, adult bee flies spend their time pollinating nearby plants. But as larvae, they prey viciously upon the larvae of other species. Adult bee flies will deposit their larvae in an aerial raid: dropping them from above to land in strategic locations where they can hatch, invade a nearby nest, and consume larvae of other insect colonies before growing up to be gentler, flower-visiting -- rather than larvae-poaching -- adults.
"An important piece of this project was being able to support a young woman in science so devoted to learning the language of species anatomy and descriptions," says Trautwein. "Watching Natalia grow and become a graduate student gives me great confidence in the young scientists who will continue to contribute to natural history collections -- our best snapshots of biodiversity in the face of great change."
New bird virus linked to beak-bending disorder
This year, scientists uncovered a fascinating new clue in the global mystery surrounding wild birds with grossly deformed beaks. Dr. Jack Dumbacher, Academy curator of ornithology and mammalogy -- alongside a team of researchers from UCSF and USGS -- identified a new virus that has been linked to Avian Keratin Disorder (AKD), a disease responsible for debilitating beak overgrowth and whose cause has remained elusive despite more than a decade of research.
This new virus -- identified from Alaska and the Pacific Northwest -- is being investigated as a potential cause of AKD and represents a critical step in understanding the emergence of this disease in wild bird populations around the world.
"Take one look at a bird suffering from Avian Keratin Disorder, and you'll understand the importance of stopping its spread," says Dumbacher. "Birds must be able to feed themselves and preen their plumage by carefully spreading waterproofing oils on their feathers. When deformed beaks restrict them from these life-giving activities, birds become cold, hungry, and often die. We're trying to understand the causes, origins, and distribution of this disorder."
After sifting through hundreds of thousands of DNA fragments (and comparing them to known virus groups among birds), scientists identified a new virus suspect belonging to the picornavirus family -- a large and diverse group that includes well-known human offenders like polio, hepatitis A, and the common cold. The team named their discovery Poecivirus after the genus of black-capped chickadee (Poecile atricapillus) from which the sequences originated, and in which AKD was first documented.
Though more research is necessary to establish Poecivirus definitively as the main cause of AKD, it remains the strongest lead yet. As part of the new virus description, the team generated a detailed map of Poecivirus' genetic material -- a tool that will enable scientists all over the world to aid in its identification among birds exhibiting clinical signs of AKD.
A fleet of beetles from Africa and China
After more than a dozen combined expeditions to the damp rainforests of Madagascar and cloud-kissed mountains of southwestern China, Dr. Dave Kavanaugh -- Academy emeritus curator of entomology -- is sharing 36 exciting new discoveries. Ground beetles are a wildly diverse group of winged and wingless predators that feast on other insects, and some are known to survive in extreme environments around the world.
Twenty-six of Kavanaugh's recent species discoveries hail from Madagascar's Ranomafana National Park -- an area of lush tropical rainforest stretching nearly 160 square miles across the southwestern portion of the island. During one 5-week expedition, Kavanaugh's daughter Kathryn (for whom he later named a beetle Chlaenius kathrynae) assisted him in the field by searching for species of ground beetles in the leaf litter.
"The first few days of one Madagascar expedition were dry as a bone, making the rainforest insects very hard to find," says Kavanaugh. "And then the rains came. It poured day and night for the next month. We worked through the storms with jungle rot on our feet from the constant damp." The rain led to the successful collection of many new beetle species, including flat-backed, fungi- and log-dwelling Eurydera oracle, named in honor of generous expedition support provided by Oracle.
Several additional new species (including three new genera) are described from the Gaoligong Mountains of China's Yunnan Province, a region where extreme physical geography has caused a jaw-dropping array of species to evolve over millennia. Since 1998, Kavanaugh and his colleagues have trekked mountains packed with endemic species -- those found nowhere else in the world. Scientists view the region as an isolated paleoenvironment, or an area that (due to its location) has remained relatively unchanged for millions of years. In less than two decades, the team has grown the list of the area's known ground beetles from 50 to 550 species.
Kavanaugh collaborates with local Chinese colleagues on the China Natural History Project to document the vast array of ground beetles and other animals and plants still being discovered in this isolated region. "Due to the restricted range and specialization of these insects, they are often some of the first to indicate significant changes to regional climate and biodiversity," says Kavanaugh, "which is why it's so important that we learn all about the life around us. You never know what clues even the smallest insects underfoot may hold to the rhythms of life on this planet."
Armored lizards of Angola
Amid outcroppings of granite in the arid, sloping lowlands of southern Angola, a newly discovered species of lizard wedges itself into particularly tight crevices, head-first. Only threatening spines are left exposed along its body and tail to deter approaching predators. Despite this clever maneuver, there was no escaping discovery by Dr. Edward Stanley, Academy herpetology research associate, who suspected this particular lizard might differ from known species in the area.
Stanley formally described this new species of armored lizard with the aid of CT scans, a type of imaging technology that combines a series of x-rays to reveal information about the lizard's uniquely armored body. Scans revealed that the tiny, bony spikes of Cordylus namakuiyus are actually embedded in the lizard's skin rather than attached to the skeleton itself.
"CT technology allowed us to visualize and measure the armoring structure in this new lizard species," says Stanley. "This is also the first time a 3D digital representation of a newly described species is freely available to download as part of a species description."
The species discovery -- the result of a joint expedition between the Academy and partner institutions in Angola -- represents a strong collaborative step towards exploring the region's extreme natural landscape. "Not much is known about Angolan species of armored lizards," says Stanley, "particularly in remote or inaccessible parts of the country, so we are excited to be exploring this biologically rich area."
Local coral discovery helps double California sanctuary
Just north of San Francisco off California's coastline, countless species thrive in the deep, chilly waters that make up the Greater Farallones National Marine Sanctuary -- one of the most biologically productive regions on the planet. Here, scientists use remotely operated vehicles, or ROVs, to explore life beneath the surface. On a 2012 expedition with NOAA, octocoral expert and Academy curator of invertebrate zoology Gary Williams set off aboard the R/V Fulmar to investigate vibrant offshore life down to 1,400 feet deep.
Among the sea stars, sea worms, snails, sponges, and crabs, Williams saw a single, whip-like stalk -- only 15 inches in length -- of a snow-white coral gently swaying in the ocean currents. Unlike the hard coral relatives that compose the famous tropical reefs closer to the ocean's surface, this soft-bodied coral species stands alone at depth and feeds on microscopic plankton floating through the water column.
Even before its formal description, the new species -- now named Swiftia farallonesica after its sanctuary home -- served as a brilliant symbol of the region's ecological importance, and helped strengthen the case for sanctuary expansion. In March 2015, NOAA ensured these sanctuaries would be protected for years to come by more than doubling their size and adding strict industry regulations on commercial fishing as well as a ban on all drilling, mining, and ship discharges. The expansion added 2,700 square miles of protected territory, reaching up to Point Arena in Mendocino County.
"Discovery is always an exciting thing," says Williams. "It's crucial to continue exploring the unknown so we can properly manage and protect these priceless marine ecosystems in our own backyard."
Read more at Science Daily
Dec 21, 2016
|These 1.9 billion-year-old marine sediments are from the East Arm of the Great Slave Lake, Canada. Thousands of samples for this study were collected from the few places on Earth that have such remaining slivers of ancient seafloor.|
Then came a fierce planetary metamorphosis. Roughly 800 million years ago, in the late Proterozoic Eon, phosphorus, a chemical element essential to all life, began to accumulate in shallow ocean zones near coastlines widely considered to be the birthplace of animals and other complex organisms, according to a new study by geoscientists from the Georgia Institute of Technology and Yale University.
Along with phosphorus accumulation came a global chemical chain reaction, which included other nutrients, that powered organisms to pump oxygen into the atmosphere and oceans. Shortly after that transition, waves of climate extremes swept the globe, freezing it over twice for tens of millions of years each time, a highly regarded theory holds. The elevated availability of nutrients and bolstered oxygen also likely fueled evolution's greatest lunge forward.
After billions of years, during which life consisted almost entirely of single-celled organisms, animals evolved. At first, they were extremely simple, resembling today's sponges or jellyfish, but Earth was on its way from being, for eons, a planet less than hospitable to complex life to becoming one bursting with it.
Earth's true genesis
In the last few hundred million years, biodiversity has blossomed, leading to dense jungles and grasslands echoing with animal calls, and waters writhing with every shape of fin and color of scale. And most every stage of development has left its mark on the fossil record.
The researchers are careful not to imply that phosphorus necessarily caused the chain reaction, but in sedimentary rock taken from coastal areas, the nutrient has marked the spot where that burst of life and climate change took off. "The timing is definitely conspicuous," said Chris Reinhard, an assistant professor in Georgia Tech's School of Earth and Atmospheric Sciences.
Reinhard and Noah Planavsky, a geochemist from Yale University, who headed up the research together, have mined records of sedimentary rock that formed in ancient coastal zones, going down layer by layer to 3.5 billion years ago, to compute how the cycle of the essential fertilizer phosphorus evolved and how it appeared to play a big part in a veritable genesis.
They noticed a remarkable congruency as they moved upward through the layers of shale into the time period where animal life began, in the late Proterozoic Eon.
"The most basic change was from very limited phosphorus availability to much higher phosphorus availability in surface waters of the ocean," Reinhard said. "And the transition seemed to occur right around the time that there were very large changes in ocean-atmosphere oxygen levels and just before the emergence of animals."
Phosphorus at the beach
Reinhard and Planavsky, together with an international team, have proposed that a scavenging of nutrients in an anoxic (nearly O2-free) world stunted photosynthetic organisms that otherwise had been poised for at least two billion years to make stockpiles of oxygen. Then that balanced system was upset and oceanic phosphorus made its way to coastal waters.
The scientists published their findings in the journal Nature. Their research was funded by the National Science Foundation, the NASA Astrobiology Institute, the Sloan Foundation and the Japan Society for the Promotion of Science.
The work provides a new view into what factors allowed life to reshape Earth's atmosphere. It helps lay a foundation that scientists can apply to make predictions about what would allow life to alter exoplanets' atmospheres, and may inspire deeper studies, here on Earth, of how oceanic-atmospheric chemistry drives climate instability and influences the rise and fall of life through the ages.
Cyanobacteria, the mother of O2
Complex living things, including animals, usually have an immense metabolism and require ample O2 to drive it. The evolution of animals is unthinkable without it.
The path to understanding how a nutrient dearth would starve out breathable oxygen production leads back to a very special kind of bacteria called cyanobacteria, the mother of oxygen on Earth.
"The only reason we have a well-oxygenated planet we can live on is because of oxygenic photosynthesis," Planavsky said. "O2 is the waste product of photosynthesizing cells, like cyanobacteria, combining CO2 and water to build sugars."
And photosynthesis is an evolutionary singularity, meaning it only evolved once in Earth's history -- in cyanobacteria.
Some other biological phenomena evolved repeatedly in dozens or hundreds of unrelated incidents across the ages, such as the transition from single-celled organisms to rudimentary multicellular organisms. But scientists are confident that oxygenic photosynthesis evolved only this one time in Earth's history, only in cyanobacteria, and all plants and other beings on Earth that photosynthesize coopted the development.
The iron anchor
Cyanobacteria are credited with filling Earth's atmosphere with O2, and they've been around for 2.5 billion years or more.
That begs the question: What took so long? Basic nutrients that fed the bacteria weren't readily available, the scientist hypothesize. The phosphorus, which Planavsky and Reinhard specifically tracked, was in the ocean for billions of years, too, but it was tied up in the wrong places.
For eons, the mineral iron, which once saturated oceans, likely bonded with phosphorus, and sank it down to dark ocean depths, far away from those shallows -- also called continental margins -- where cyanobacteria would have needed it to thrive and make oxygen. Even today, iron is used to treat waters polluted with fertilizer to remove phosphorus by sinking it as deep sediment.
The researchers also used a geochemical model to show how a global system with high iron concentration and low phosphorus availability combined with low nitrogen availability in ocean shallows could perpetuate itself in a low-oxygen world.
"It looks to have been such a stable planetary system," Reinhard said. "But it's obviously not the planet we live on now, so the question is, how did we transition from this low-oxygen state to where we are now?"
What ultimately caused that change is a question for future research.
Phosphorus starting pistol
But something did change about 800 million years ago, and cyanobacteria and other minute organisms in continental margin ecosystems got more phosphorus, the backbone of DNA and RNA, and a main actor in cell metabolism. The bacteria became more active, reproduced more quickly, ate lots more phosphorus and made loads more O2.
"Phosphorus is not only essential for life," Planavsky said. "What's implicit in all this is: It can control the amount of life on our planet."
When the newly multiplied bacteria died, they fell to the floor of those ocean shallows, stacking up layer by layer to decay and enrich the mud with phosphorus. The mud eventually compressed to stone.
"As the biomass increased in phosphorus content, the more of it landed in layers of sedimentary rock," Reinhard said. "To scientists, that shale is the pages of the sea floor's history book."
Scientists have thumbed through them for decades, compiling data. Planavsky and Reinhard analyzed some 15,000 rock records for their study.
Read more at Science Daily
|The scientists examined 6,000 Daphnia, waterflea, as part of the study.|
Populations that clone themselves are entirely female and do not need sex to reproduce. As sex requires males, and males do not produce offspring themselves, an entirely clonal population should always reproduce faster than a sexual one.
Yet while some animal and plant species can reproduce without sex, such as komodo dragons, starfish and bananas, sex is still the dominant mode of reproduction in the natural world.
Scientists know that sex allows genes to mix, allowing populations to quickly evolve and adapt to changing environments, including rapidly evolving parasites.
However, for sex to beat cloning as a reproduction strategy, there must be large-scale benefits that make a difference to the next generation. The theory has been difficulty to test as most organisms are either wholly sexual or clonal so cannot be compared easily.
A team of experts from the University of Stirling have taken an innovative approach to test the costs and benefits of sex. Using an organism that can reproduce both ways, the waterflea, researchers found sexually produced offspring were more than twice as resistant to infectious disease as their clonal sisters.
Dr Stuart Auld of the Faculty of Natural Sciences, said: "One of the oldest questions in evolutionary biology is, why does sex exist when it uses up so much time and energy?
"Sex explains the presence of the peacock's tail, the stag's antlers and the male bird of paradise's elaborate dance. But if a female of any of these species produced offspring on her own, without sex, her offspring should come to dominate, while the other females watch the redundant males fighting and dancing. So, why are we not surrounded by clonal organisms?
"By comparing clonal and sexual daughters from the same mothers, we found sexually produced offspring get less sick than offspring that were produced clonally. The ever-present need to evade disease can explain why sex persists in the natural world in spite of the costs."
Read more at Science Daily
More precise measurements of this emitted light could unearth clues that might finally help solve the mystery of why there is so much less antimatter than normal matter in the universe, researchers say.
For every particle of normal matter, there is an antimatter counterpart with the same mass but the opposite electrical charge. The antiparticles of the electron and proton, for instance, are the positron and antiproton, respectively.
When a particle meets its antiparticle, they annihilate each other, giving off a burst of energy. A gram of antimatter annihilating a gram of matter would release about twice the energy as the nuclear bomb dropped on Hiroshima, Japan. (You don't have to worry about antimatter bombs popping up anytime soon; researchers are very far from creating anywhere near a gram of antimatter.)
It remains a mystery why there is so much more matter than antimatter in the universe. The Standard Model of particle physics — the best description yet of how the basic building blocks of the universe behave — suggests that the Big Bang should have created equal amounts of matter and antimatter.
Scientists would like to learn more about antimatter to see if it behaves differently from matter in a way that could help solve the puzzle of why the universe has so little antimatter.
One key set of experiments would involve shining lasers on antimatter atoms, which can absorb and emit light much like atoms of regular matter. If antihydrogen atoms emitted a different spectrum of light than hydrogen atoms, such spectral differences could yield insights on other ways matter and antimatter differ, the researchers said.
Now, for the first time, scientists have used lasers to carry out a spectral analysis of antihydrogen atoms.
"I like to call this the Holy Grail of antimatter physics,"said study co-author Jeffrey Hangst, a physicist at Aarhus University in Denmark. "I've been working for more than 20 years to make this possible, and this project has finally come together after many difficult steps."
The researchers experimented with antihydrogen, which is the simplest atom of antimatter, just as hydrogen is the simplest atom of regular matter. Antihydrogen atoms each consist of one antiproton and one positron.
Creating enough antimatter for researchers to examine has proven highly challenging. To create antihydrogen atoms, the researchers mixed clouds of about 90,000 antiprotons with clouds of about 1.6 million positrons (or antielectrons), yielding about 25,000 antihydrogen atoms per attempt using the ALPHA-2 apparatus, which is an antimatter generation and trapping system, at the European Organization for Nuclear Research (CERN) in Switzerland.
After the researchers create the antihydrogen atoms, "you have to hold on to them, and that's very difficult," Hangst told Live Science. Antihydrogen is electrically neutral, which means that it cannot be held in place using electric fields, "and you have to keep it away from matter, so it has to be kept in high vacuum," he said. In addition, antimatter is best kept at temperatures close to absolute zero (minus 459.67 degrees Fahrenheit, or minus 273.15 degrees Celsius), so it is slow-moving and easier to hold on to than antihydrogen atoms.
The researchers trapped antihydrogen in very strong magnetic fields. "We can now hold about 15 antihydrogen atoms at a time," Hangst said.
Then, they shone a laser on the antihydrogen, which caused the atoms to give off light. The scientists then measured the spectrum of light that antihydrogen gave off with a precision of about a few parts in 10^10 — that is, a 1 with 10 zeroes behind it. In comparison, researchers can currently measure these properties of hydrogen to a precision of a few parts in 10^15. "We want to measure antihydrogen with the same precision as hydrogen, and we see no reason why we can't do that in the future," Hangst said.
Read more at Discovery News
As the second-brightest star on the shoulder of Orion (The Hunter), Betelgeuse is a mangled stellar mess. Coming to the end of its life, the massive red supergiant is convulsing as its superheated upper layers become stripped away by violent stellar winds. These winds are creating vast clouds of gas, a prelude to the mayhem just around the corner.
Having lived its comparatively short life of around 8 million years (to put that in perspective, our middle-aged sun has been around for 5 billion years), rapidly burning away its supply of hydrogen fuel, this massive bloated star only 700 light-years from Earth is now in the process of fusing heavier elements together. Within the next million years (some estimately put it within the next 100,000 years), Betelgeuse will become so unstable that it will explode as a supernova, a fact that has spawned all kinds of silly doomsday theories for life on Earth.
Though Betelgeuse is so close and it is one of the most studied stars in the sky, it still holds many mysteries. And in new research published by the journal Monthly Notices of the Royal Astronomical Society, J. Craig Wheeler of The University of Texas at Austin and his team of international undergraduate students have uncovered something peculiar about the star's spin.
When a star reaches the end of its life and expands like Betelgeuse has, physics dictates that its rate of spin should slow down. A good analogy for this effect is if an ice skater spins on the spot and extends her or his arms outward, their rate of spin slows. The same physics applies to an expanding star. But that's not the case here, Betelgeuse is spinning way too fast!
"We cannot account for the rotation of Betelgeuse," said Wheeler in a statement. "It's spinning 150 times faster than any plausible single star just rotating and doing its thing."
Wheeler's team took on this puzzle and ran a series of computer simulations in an attempt to explain what's going on and one scenario emerged.
"Suppose Betelgeuse had a companion when it was first born?" he pondered. "And let's just suppose it is orbiting around Betelgeuse at an orbit about the size that Betelgeuse is now. And then Betelgeuse turns into a red supergiant and absorbs it — swallows it."
To explain the current spin of Betelgeuse, the massive star would have had to swallow a star of a similar size to our sun. Also, as the majority of stars come in in pairs (or more), it's certainly within the realms of possibility that it evolved with a smaller stellar sibling in tow.
Read more at Discovery News
Dec 20, 2016
"It's a bizarre-looking fish with a pointed snout," said Lonny Lundsten, a senior research technician at Monterey Bay Aquarium Research Institute (MBARI) in California. "It has a long, pointed, tapering tail, relatively large eyes, [and] it's almost entirely grayish-blue."
The rare, deep-sea fish — called a "ghost shark" for its appearance, but also known as the pointy-nosed blue ratfish — made its video debut after researchers recorded the animal via remotely operated underwater vehicles (ROVs) off the coasts of Hawaii and California. The videos, six in all, provide the first evidence that this species of ratfish lives in the Northern Hemisphere, Lundsten told Live Science.
The videos were taken between 2000 and 2007, but it was only in October that researchers published the findings in the journal Marine Biodiversity Records, said Lundsten, who co-authored the study with two of his colleagues.
|The Monterey Bay Aquarium Research Institute's ROV (remotely operated underwater vehicle) caught footage of six different ghost-shark individuals. Notice that the fish are swimming over rocky, rather than soft sediment.|
Despite naming the newfound species, researcher Dominique Didier, a professor of biology at Millersville University in Pennsylvania, had never seen a live specimen. Instead, she and her colleague studied 23 dead H. trolli specimens caught as bycatch by trawlers (deep-sea fishing boats that catch marine animals with large nets) in the southwestern Pacific Ocean. These fish were all found in the Southern Hemisphere off the coasts of Australia, New Zealand, New Caledonia, and the Lord Howe Rise (a deep-sea plateau) and Norfolk Ridge formations, Lundsten said.
But Didier did get a chance to see the MBARI videos and confirmed that the fish in the footage with wing-like fins were likely H. trolli, Lundsten said.
Lundsten added that H. trolli's Frankenstein-like stitches are actually sensory organs that cover the fish's entire body, especially its face. These organs can sense minute movements and vibrations in the surrounding water, which helps the fish hunt prey, said Dave Ebert, who co-authored the study with Lundsten and Amber Reichert, a graduate student of marine science at California State University (Cal State). Ebert is also the program director of the Pacific Shark Research Center at Cal State's Moss Landing Marine Laboratories.
In addition, male ratfish "have a strange sexual-related organ that's on the top of their head," Lundsten said. "It's a club-shaped thing that has spines on it, and it's used for grasping and better positioning the female during copulation."
Read more at Discovery News
So suggests a new report published in the journal Cell Biology led by researchers from Germany's Alfred Wegener Institute.
The cute octopod in question is a tiny cephalopod found earlier this year in the Hawaiian archipelago, one that is likely an undescribed, new species.
In the new study, scientists have found that the creature tends to populate areas of manganese crust that are rich in the kinds of metals used in the manufacture of consumer electronics. The animals deposit their eggs among dead sponges in such areas. And, as they live at depths that can exceed 13,000 feet (4,000 meters), the water is so cold that eggs likely take years to hatch.
With such desirable metals located right where it likes to breed, then, the octopus could be in trouble.
"The brooding [location] is important as these sponges only grow in some areas on small, hard nodules or rocky crusts of interest to mining companies because of the metal they contain," said study lead Autun Purser, of the Alfred Wegener Institute, in a statement. "The removal of these nodules may therefore put the life cycle of these octopods at risk."
Mining the seafloor for all of its riches could make it impossible for the octopus to bounce back.
"This would be a great loss to biodiversity in the deep sea and may also have important knock-on effects," said Purser. "Octopods are sizable creatures, which eat a lot of other smaller creatures, so if the octopods are removed, the other populations will change in difficult-to-predict ways."
In the meantime, however, nearly two-dozen contracts have been issued for mining exploration operations in the Pacific, Indian and Atlantic oceans.
It's easy to understand why. The bottom of the sea, depending on where you are, can be rich in the kinds of nodules of metal Purser noted. The so-called polymetallic nodules can contain a whole host of metals, including nickel, aluminum, silicone, rare earth metals, and iron.
Read more at Discovery News
But now, scientists have used observations by the European Space Agency's Swarm satellites to identify another sort of jet stream, one that's made of molten metal instead of air and is located 1,865 miles beneath the Earth's surface, stretching from Siberia to Alaska.
The findings, contained in an article just published in the online edition of Nature Geoscience, depict a previously unknown geological feature that may yield secrets about the Earth's inner workings.
The jet stream inside the Earth is located along the border of two regions of the Earth's core, and it's about 261 miles in width. It moves about 25 miles in the course of a year. That's far slower than the hundreds of miles per hour at which the atmospheric jet streams travel, but three times faster than other parts of the outer core and hundreds of thousands of times faster than the Earth's tectonic plates. The interior jet stream gradually is accelerating, according to the scientists' findings.
"What's most surprising about the jet is that it's likely been in the core for many years and no-one has seen it before — not even with previous satellite missions," lead researcher Phil Livermore, an associate professor in the School of Earth and the Environment at the University of Leeds, said in an email. "The jet is likely to have been around in the core for some hundreds of millions of years, and we've only just glimpsed it through the technical-revolution of the Swarm mission."
Swarm, launched in 2013, uses a trio of satellites rather than just one probe to produce extremely high-resolution images of the Earth's magnetic field and how it moves. By analyzing that data, scientists essentially can peer inside the planet.
"Swarm measures the magnetic field in space, from which it is possible to create an image of the magnetic field at the edge of the Earth's core," Livermore said. "Although the mantle is solid rock, the magnetic field can 'see' inside, and hence produce an x-ray view of the inside of our planet. At high latitude, at the edge of the core, there are patches of intense magnetic field that we can track over time. it is these features that allows us to infer that the iron in the core is moving in a jet. We cannot see the jet itself, but we can see its effect by the fact that it drags around magnetic features."
Livermore described the jet stream as "a very significant" feature of the core, and said that gaining knowledge about it will help scientists to better understand the interior workings of the planet.
"The jet stream probably doesn't have any immediate impacts for us on the Earth surface, but it may shed light on the dynamical state of the liquid core," he said. "The more we know about how the core operates, the more chance we will have in, for example, being able to predict whether the current weakening of the magnetic field is a precursor to a global reversal."
Read more at Discovery News
The star, called HIP68468, shares some similarities to our sun and is known to play host to a system of planets. A large gas giant-like planet, approximately 50 percent bigger than Neptune, has been spotted, along with a "super-Earth" world. The super-Earth orbits extremely close to its host star, completing one orbit every three days. But it would appear that there was at least one more planet that used to exist, but has since become stellar toast.
While studying HIP68468, which is located 300 light-years away, the international team of astronomers detected high quantities of lithium in its atmosphere, along with other elements that are associated with rocky planets. By considering the star's age of six billion years, any lithium it formed with would have been long gone, so a fresh batch of lithium must have fallen in recently. Taking into account the observed quantity of lithium and other minerals, the researchers were able to deduce that an entire planet, approximately six times the mass of Earth, likely got consumed by the star in its recent history.
"It's as if we saw a cat sitting next to a bird cage," said Debra Fischer, of Yale University, in a statement. "If there are yellow feathers sticking out of the cat's mouth, it's a good bet that the cat swallowed a canary."
"This study of HIP68468 is a post-mortem of this process happening around another star similar to our sun," she added. "The discovery deepens our understanding of the evolution of planetary systems."
Our solar system may seem to be a stable place, with the planets carving out unchanging orbits. But over the evolution of stars and planets, gravitational instabilities tweak planetary orbits, often causing huge migrations. Migrating planets can have a myriad of effects on other planets, asteroids and comets, and even the stars themselves. In the case of HIP68468, it's thought that an inner planet migrated too close to the superheated furnace and was ultimately consumed by the star.
And using research such as this, we can look at the solar system's planets, perhaps seeing the ultimate demise of planets we know and love. Though Earth can rest easy for now, Mercury, the solar system's innermost planet, might not be so lucky.
Read more at Discovery News
Dec 19, 2016
|Tropical rainforest landscape in the Amazon.|
The study, published Dec. 19 in Nature Plants, suggests that this problem may stem from a common tendency in fieldwork to report leaf measurements taken in partially shaded conditions as existing in more fully sunlit conditions.
As a result, global plant databases and models may require updating to better account for plant responses to full-sun conditions, said Trevor F. Keenan, a research scientist in Berkeley Lab's Earth and Environmental Sciences Area who led the study.
"Often when researchers are in the field, it's hard to get to leaves at the top of trees," Keenan said, particularly in densely vegetated areas such as tropical forests where the canopies can reach over 100 feet in height.
"In other cases, understory plants grow mostly in the shade, so it is impossible to sample in full sun. Traits vary quite a lot in the canopy, so if you don't sample from the top all of your samples will be biased," he said.
Study finds large light-dependent variations in leaf traits
In plant fieldwork, full-sun conditions are defined as those in which a plant receives the maximum amount of sunlight, typically at the top of a canopy, but most leaves do not grow in full-sun conditions.
Leaves at the bottom of the canopy in a tropical rainforest may receive 100 times less sunlight than those at the top of the canopy, Keenan said. And many leaf characteristics -- which are integral to vital leaf functions such as carbon uptake and photosynthesis -- can vary 20-fold between the top and bottom leaves on the same plant.
"For example, the highest concentration in nitrogen is at the top, where you have the most sunlight. Plants allocate a lot of nutrients there so they can 'profit' from it the most," Keenan said.
Cutting to the root of a data problem
Keenan and U?lo Niinemets, a researcher from the Estonian University of Life Sciences and Estonian Academy of Sciences, evaluated leaf data from several databases -- covering hundreds of plant species and spanning most regions of the world -- in the latest study. They used data from those studies that reported extra information about the specific location of the sampled leaves in the canopy as a benchmark for other studies' data. The research was conducted as Keenan and colleagues were assembling a new global database for plant research.
The misreported sun vs. shade conditions are likely most pronounced in tropical regions, Keenan said. Because these regions of tropical vegetation are also considered to be the planet's largest "carbon sinks" in removing carbon dioxide from the atmosphere, "These are some of the most important areas to focus on," he said.
Better accounting of light conditions that sampled leaves are growing in could help to improve models that account for plants' total rate of photosynthesis and better quantify their role as a carbon sink, for example, and for plants' adaptability to changing conditions. It can also identify important correlations between which plant traits are most pronounced under different lighting conditions.
More accurate sampling methods can ultimately help improve scientists' understanding of whole ecosystem structure and function, and to understand how plants respond to factors such as climate change, the study states.
In addition to improved reporting of sunlit conditions, there is also a need for better accounting of plant ages in field studies, as age may affect leaf chemistry and function, according to the study.
The study concludes that field studies must take more care in accurately reporting sunlit vs. shaded conditions and age-driven trait responses in leaves. "These results will hopefully help to improve field measurement strategies," Keenan said.
Combining field data with simulations and theory
More standardized fieldwork, in parallel with new computational tools and theoretical work, will contribute to better global plant models, Keenan said. Researchers will likely tap the supercomputing capabilities of Berkeley Lab's National Energy Research Scientific Computing Center (NERSC) in upcoming modeling work.
"We really don't know how plants are going to acclimate to a changing climate," Keenan said, noting that Lab researchers are developing a theory for why plants acclimate and change their allocations of nutrients within the canopy. "We can use this to better understand why trait values vary."
New techniques are emerging to improve data collection in the field, Keenan also said. The study notes that some field research has used a shotgun approach to sample leaves at the top of the canopy -- firing a shotgun to clip off leaves that are otherwise out of reach -- though this technique alters the water flow that exists in attached leaves, so it can affect photosynthesis measurements.
Read more at Science Daily
The data has been made available by the international Pan-STARRS project, which includes scientists from Queen's University Belfast, who have predicted that it will lead to new discoveries about the Universe.
Astronomers and cosmologists used a 1.8-metre telescope at the summit of Haleakalā, on Maui, Hawaii, to repeatedly image three quarters of the visible sky over four years.
Three billion sources
The data they have captured in the Pan-STARRS1 Surveys is made up of three billion separate sources, including stars, galaxies, and other space objects.
This immense collection of information contains two petabytes of computer data -- equivalent to one billion selfies or one hundred times the total content of Wikipedia.
Pan-STARRS is hosted by the University of Hawaii Institute for Astronomy, which is releasing the data alongside the Space Telescope Science Institute in Baltimore, USA.
The international collaboration also includes Queen's University Belfast and the Universities of Durham and Edinburgh and is supported by NASA and the National Science Foundation.Durham's contribution was funded by a generous donation from the Ogden Trust and Durham University.
Luminous distant explosions
Queen's University Belfast Professor Stephen Smartt, who is Chair of the Pan-STARRS1 (PS1) Science Council, said: "We've worked on this project for more than five years at Queen's and have found the most luminous distant explosions in the Universe and also nearby asteroids in our solar system.
"It was a fantastic team effort and now we hope the whole science community will benefit from this public release of our data."
In May 2010, the Panoramic Survey Telescope & Rapid Response System, or Pan-STARRS, observatory embarked on a digital survey of the sky in visible and near infrared light.
This was the first survey with a goal of observing the sky very rapidly over and over again, looking for moving objects and transient or variable objects, including asteroids that could potentially threaten Earth.
Dr Ken Chambers, Director of the Pan-STARRS Observatories, at the University of Hawaii, said: "The Pan-STARRS1 Surveys allow anyone to access millions of images and use the database and catalogues containing precision measurements of billions of stars and galaxies.
"Pan-STARRS has already made discoveries from Near Earth Objects and Kuiper Belt Objects in the Solar System to lonely planets between the stars; it has mapped the dust in three dimensions in our galaxy and found new streams of stars; and it has found new kinds of exploding stars and distant quasars in the early Universe."
Read more at Science Daily
King, a Northern Illinois University (NIU) alumnus, investigated the matter further with a few colleagues and found out that she was not just imagining the connection. According to the new study, published in the journal Applied Animal Behavior Science, stress can cause dogs to go prematurely gray.
"It is not known if dogs go completely gray due to stress," King told Seeker. "I have seen in practice where dogs will have full gray muzzles and gray around the eyes."
She, NIU professor Thomas Smith, animal behaviorist Peter Borchelt, and researcher Temple Grandin examined 400 dogs in Colorado at dog parks, dog shows, veterinary clinics and other venues. These observations, plus dog behavior questionnaires given to the pets' owners, revealed a link between a canine's documented anxious behavior and its likelihood of developing gray hairs between the ages of 1–4, when color changes due to natural aging would be unexpected.
Independent raters looked at photos of the dogs and judged the level of muzzle grayness for each. Their judgments corresponded with those of the scientists and dog owners.
As for humans, both genetics and environment can play into a dog's mood. A dog's environment is further complicated by the owner's physical and mental health.
"There have been some recent studies that suggest that dogs can pick up their owners' emotions," King, who has her own animal behavior practice in the Denver, Colorado, area explained.
Extremely stressed out pets will even sometimes excessively lick their fur in certain places, causing bald patches to form. The ingested fur can cause further problems.
She says dog owners should think of muzzle graying—easier to see in dark-haired breeds—as a symptom for possible underlying issues.
"Anxiety and stress can present health risks for dogs, including risk of illness and shortened life expectancy," she said. "Premature muzzle grayness could serve as one of several markers for anxiety in young dogs. Addressing anxiety and impulsiveness issues at an early age can lead to a higher quality of life."
Read more at Discovery News
The prehistoric cooked food remains are so old that they predate plant domestication and agriculture in the region by at least 4,000 years, according to a new study in the journal Nature Plants.
Animal fats known as lipids were also found on the ancient ceramic vessels.
The evidence indicates the foods included "grains cooked to make porridge-type dishes that are very common in Africa even today," and boiled "leafy plants, sedges or aquatic plants" that were likely mixed with meat and/or animal fats, lead author Julie Dunne, a post-doctoral research associate at the University of Bristol School of Chemistry, told Seeker.
"This suggests possibly stew-type dishes comprising animal fats and grains or leafy vegetables," Dunne added.
She and her team made the determinations after studying the unglazed pottery, which was found at two sites in the Libyan Sahara: Takarkori and Uan Afuda. At the time of pottery's use, the sites were part of a green savannah characterized by coarse grasses and scattered tree growth.
Chemical signatures taken from the pottery show that a wide variety of plant products were being cooked back in the day. These included parts of fig trees, cattails, cypress, burr or carrot seed grass, cassia and desert date. Also found at the site were millet, foxtail grass and barnyard grass and its fruits. Fruits from Echinochloa, Panicum and Setaria were additionally discovered.
Dunne said that "many of these plants are still consumed today."
|Botanical remains including leaves, fruits and grains found at the Takarkori rock shelter. (Details on page 2 of the paper, underneath Figure 1.)|
Grindstones dating to even earlier times have been found in North Africa. They suggest that plant products were processed and heated for eating earlier than 10,200 years ago, but the new study provides the first direct evidence for cooking.
It's thought that pottery was independently invented twice during human history: first in East Asia around 16,000 years ago, and more recently in North Africa at around the time that the food-encrusted pots were used.
The invention marked a breakthrough. As Dunne explained, "the ability to boil plants for long periods of time in newly invented ceramic vessels would have significantly increased the range of plants prehistoric people could eat."
The food might have been soft enough for infants, she and her team point out. If babies were able to eat the cooked foods, then this could have led to earlier weaning and shorter times between births, thereby enhancing the fertility of women in early pastoral communities.
|Rock art painting showing a human figure collecting plants.|
Things began to change in the Libyan Sahara around 5,000–6,000 B.C., however, when cattle and other animals started to be raised for their dairy products. Some early ceramic vessels reveal that the latter were cooked too and sometimes with plant products, such as for porridge.
Read more at Discovery News
Dec 18, 2016
Diseases that jump from other vertebrate hosts to humans are a major public health threat, but the evolutionary mechanisms behind these jumps are poorly understood. With its long history of jumping between host species, the rabies virus offers a good opportunity to identify evolutionary patterns associated with such shifts.
Cécile Troupin of Institut Pasteur, Paris, and colleagues compared 321 viral genome sequences collected from 66 countries over 65 years. The analysis revealed very different evolutionary patterns for bat-related rabies, which is found in bats and some carnivores; versus dog-related rabies, which is responsible for almost all human cases of rabies and is found in both dogs and wild carnivores.
The data suggest that different subgroups of bat-related rabies do not evolve uniformly, but dog-related rabies usually evolves at a steady rate. For dog-related rabies, host jumping was linked to multiple evolutionary patterns, such as parallel changes in amino acid sequences between different host species. The data also suggest that dog-related rabies may not need to evolve much to jump to new carnivore hosts.
Looking deeper into dog-related rabies, the scientists found evidence to suggest that, after trade between continents began in the 15th century, dog-related rabies rapidly spread worldwide. The authors say that the particular combination of species currently infected by dog-related rabies probably arose as a combined effect of historical spread by humans and host jumping.
Read more at Science Daily
"Some of the world's largest and most valuable diamonds, like the Cullinan or Lesotho Promise, exhibit a distinct set of physical characteristics that have led many to regard them as separate from other, more common diamonds. However, exactly how these diamonds form and what they tell us about the Earth has remained a mystery until now," explains Dr. Wuyi Wang, GIA's director of research and development, and an author of the study.
Large gem diamonds like the Cullinan have a set of physical characteristics that distinguish them from other kinds of diamonds. The new research shows these Cullinan-like gems sometimes have small metallic inclusions -- or internal characteristics -- trapped within them. The metallic inclusions coexist with traces of fluid methane and hydrogen. In addition to the metallic inclusions, some of these exceptional diamonds contain mineral inclusions that show the diamonds formed at extreme depths, likely within 360-750 km (approximately 224-466 miles) in the convecting mantle. This is much deeper than most other gem diamonds, which form in the lower part of continental tectonic plates at depths of 150-200 km (approximately 93-124 miles).
"This new understanding of these large, type IIa diamonds resolves one of the major enigmas in the study of diamond formation -- how the world's largest and most valuable diamonds formed," says Smith. "The composition of the inclusions, however, provides the story."
The metallic inclusions are a solidified mixture of iron, nickel, carbon and sulfur, also containing traces of fluid methane and hydrogen in the thin tiny space between the metallic phases and the encasing diamond. Pure carbon crystallized in this mix of molten metallic liquid in Earth's deep mantle to form diamonds. Small droplets of this metallic liquid were occasionally trapped within the diamonds as they grew. During cutting and polishing, parts of the diamond that contain inclusions are often cut off or polished away to craft exquisite polished gems with minimal flaws. These cut diamond pieces are not normally available for research, but because of GIA's unique position as an independent, nonprofit research organization, Dr. Smith and his coauthors were able to study the inclusions for this investigation.
"Previous experiments and theory predicted for many years that parts of the deep mantle below about 250 km depth contain small amounts of metallic iron and have limited available oxygen. Now, the metallic inclusions and their surrounding methane and hydrogen jackets in these diamonds provide consistent, systematic physical evidence to support this prediction," explains Smith.
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