Mar 21, 2015
Among elephant remains some 500,000 years old at a Lower Paleolithic site in Revadim, Israel, Prof. Ran Barkai and his graduate students Natasha Solodenko and Andrea Zupanchich of Tel Aviv University's Department of Archaeology and Ancient Near Eastern Cultures recently analyzed "handaxes" and "scrapers," universally shaped and sized prehistoric stone tools, replete with animal residue.
The research, published recently in PLOS ONE, represents the first scientifically verified direct evidence for the precise use of Paleolithic stone tools: to process animal carcasses and hides. The research was done in collaboration with Drs. Stella Ninziante Cesaro and Cristina Lemorini of La Sapienza, University of Rome, and Dr. Ofer Marder of Ben-Gurion University of the Negev.
Putting the puzzle together
"There are three parts to this puzzle: the expansion of the human brain, the shift to meat consumption, and the ability to develop sophisticated technology to meet the new biological demands. The invention of stone technology was a major breakthrough in human evolution," Prof. Barkai said. "Fracturing rocks in order to butcher and cut animal meat represents a key biological and cultural milestone.
"At the Revadim quarry, a wonderfully preserved site a half-million years old, we found butchered animal remains, including an elephant rib bone which had been neatly cut by a stone tool, alongside flint handaxes and scrapers still retaining animal fat. It became clear from further analyses that butchering and carcass processing indeed took place at this site."
Through use-wear analysis -- examining the surfaces and edges of the tools to determine their function -- and the Fourier Transform InfraRed (FTIR) residue analysis which harnesses infrared to identify signatures of prehistoric organic compounds, the researchers were able to demonstrate for the first time direct proof of animal exploitation by flint tools.
"Archaeologists have until now only been able to suggest scenarios about the use and function of such tools. We don't have a time machine," Prof. Barkai said. "It makes sense that these tools would be used to break down carcasses, but until evidence was uncovered to prove this, it remained just a theory."
A prehistoric Swiss army knife
While the question of their function and production remained unanswered until now, there was little doubt that the handaxe and scraper, found at prehistoric sites all around the world, were distinct, used for specific purposes. By replicating the flint tools for a modern butchering experiment, and then comparing the replicas with their prehistoric counterparts, the researchers determined that the handaxe was prehistoric man's sturdy "Swiss army knife," capable of cutting and breaking down bone, tough sinew, and hide. The slimmer, more delicate scraper was used to separate fur and animal fat from muscle tissue.
"Prehistoric peoples made use of all parts of the animal," said Prof. Barkai. "In the case of the massive elephant, for example, they would have needed to use both tools to manage such a challenging task. The knowledge of how to make these tools was precious, and must have been passed along from generation to generation, because these tools were reproduced the same way across great territorial expanses and over hundreds of thousands of years.
Read more at Science Daily
This week, air pollution in the City of Light spiked to such unpleasant levels that on Wednesday, the Eiffel Tower was obscured by a brown haze. In an effort to quell the crisis, Paris Mayor Anne Hidalgo has called for the national government to impose emergency traffic restrictions that essentially would only allow every other car on the highways to enter the city limits, according to the French newspaper Le Monde. So far, French minister of ecology Segolene Royal has resisted imposing such severe limits, though she might consider it on Monday if the situation doesn’t improve.
In the meantime, cars are banned from traveling at speeds of more than 14 miles per hour, and Parisian commuters are being offered free use of public transportation, in an effort to reduce auto exhaust.
A map of air quality measurement stations in Paris and nearby areas shows that numerous locations have an Air Quality Index (AQI) level of between 151 and 200, at which even normally healthy individuals begin to experience respiratory effects, and people who are more sensitive to air quality have more distress.
Plumelabs.com, a website that offers data on pollution in cities around the world, put the average AQI level in Paris on Friday at 136, far higher than even New Delhi or Beijing.
Part of that worry is the smog also will cause an increase in PM10 particulates -- that is, particles smaller than 10 micrometers across -- which are small enough to get into the lungs and cause damage.
The pollution in Paris is so bad that it’s blowing across the English Channel and causing smog in Wales, BBC News reports.
Read more at Discovery News
Mar 20, 2015
The study released by the European Commission, the EU executive arm, is the first on the European wild bee population, less known than the domestic variety but just as important to pollination of crops.
"The report reveals that 9.2 percent of European wild bee species are threatened with extinction, while 5.2 percent are considered likely to be threatened in the near future," the commission said.
The assessment was published as part of the International Union for Conservation of Nature (IUCN) European Red List of Bees and the Status and Trends of European Pollinators (STEP) project.
Its authors said the study provided the "best understanding" so far on the 1,965 species surveyed but added that knowledge was incomplete because of an "alarming lack of expertise and resources."
The IUCN said the study, which was co-funded by the European Commission, demonstrates the urgency in investing in research to halt the decline of wild bees which, it added, play "an essential role in pollinating crops."
"If we don?t address the reasons behind this decline in wild bees, and act urgently to stop it, we could pay a very heavy price indeed," said Karmenu Vellu, the European Commissioner for the environment.
Read more at Discovery News
This year, spring officially starts at 6:45 p.m. EDT on March 20, according to the U.S. National Weather Service (NSW). At that exact moment, which is called the vernal equinox, the Earth's axis will reach a halfway mark, where it points neither toward the sun (as it does on the summer solstice) nor away from the sun (as it does on the winter solstice), said Gavin Schmidt, the director of the Goddard Institute for Space Studies in New York City.
But for thousands of years, spring has been losing time in the Northern Hemisphere. This year, summer is the longest season, with 93.65 days, followed by spring with 92.76 days, autumn with 89.84 days and winter with 88.99 days, said Larry Gerstman, an amateur astronomer in New York. (Gerstman got his values from "The Astronomical Tables for the Sun, Moon and Planets," second edition, written by Jean Meeus and published in 1995 by Willmann-Bell, Inc.)
As the years go on, spring will lose time to summer, and winter will lose time to autumn. In the year 3000, the seasonal lengths will have shifted in the Northern Hemisphere: summer will be 93.92 days, while spring will be 91.97 days, autumn 90.61 days and winter 88.74 days, Gerstman said.
But why is this happening?
The Earth's seasons are caused by the tilt of the Earth on its axis (not by how close the planet is to the sun). This tilt of 23.5-degrees from the straight-up-and-down position means that for six months of the year, the Earth's Northern Hemisphere is leaning slightly toward the sun, whereas during the other six months, the Southern Hemisphere leans toward the sun.
The main reason spring is getting shorter is that the Earth's axis itself moves, much like a wobbling top, in a type of motion called precession.
Spring ends at the summer solstice, and because of precession, the point along the Earth's orbit where the planet reaches the summer solstice shifts slightly. Next year, the planet will reach the point in its orbit of the solstice slightly earlier.
Spring will end, and summer will begin, just a little bit earlier in the year.
Over thousands of years, the shift in the time of the vernal equinox becomes more apparent. For instance, spring will be shortest in about the year 8680, measuring about 88.5 days, or about four days shorter than this year's spring, Gerstman said. (After that point, spring will lengthen again.)
Why spring is shorter than summer
At the point of perihelion, the Earth is about 91.6 million miles (148 million kilometers) away from the sun. When the Earth is farthest from the sun — in early July, during aphelion — the distance is about 94.8 million miles (153 million km).
This change in distance from the sun, of about 3.2 million miles (5 million km), isn't much compared to Earth's total distance from the sun, according to NASA, and people don't notice it. But the difference is large enough to change the speed of the Earth as it travels in its orbit. The Earth moves fastest when it's closest to the sun, and slowest when it's farthest, Schmidt said.
"We go through winter quite quickly, whereas in the summertime we're far away from the sun, and so we're going to go slower,"Schmidt told Live Science.
This change in speeds affects the length of the seasons. The Earth moves the fastest along its orbit path between December and March, hence both winter and spring are shorter than summer and autumn, he said.
In the year 1246, Earth reached perihelion on the day of December solstice, said Joe Rao, a New York based meteorologist and astronomer (Rao is also a contributing writer at Live Science.) This year, Earth reached perihelion on Jan. 4.
"Near the year 3000, perihelion will take place near Jan. 20, and near the year 4000, it will take place near Feb. 7, and so on," Rao told Live Science in an email.
At these distant dates, the Earth will be moving at its fastest speed later during the year, making spring even shorter. Perihelion will occur on the March equinox in the year 6430.
But spring will be shortest when perihelion occurs halfway through the season. And eventually, as perihelion and precession continue to change Earth's speed and wobble, spring will lengthen again, Schmidt said.
Read more at Discovery News
This multistate partnership brings together top law enforcement officers representing nearly 30 million Americans as they seek to ensure that herbal supplement manufacturers and retailers comply with the law.”
Four national retailers—Walmart, Walgreens, GNC, and Target—removed herbal supplements from their shelves in the wake of an investigation by the New York State attorney general’s office which found that the “health” medications were badly mislabeled.
Bottles of herbal pills, for example, often contained doses of the active ingredient that were so small as to be ineffective—when the supplements contained any of the herb at all. Often the consumers were buying products that were contaminated or included inert, inexpensive fillers such as powdered rice.
In fact the investigation found that “four out of five of the products did not contain any of the herbs on their labels. The tests showed that pills labeled medicinal herbs often contained little more than cheap fillers like powdered rice, asparagus and houseplants, and in some cases substances that could be dangerous to those with allergies,” according to “The New York Times.”
Even worse, “a popular store brand of ginseng pills at Walgreens, promoted for ‘physical endurance and vitality,’ contained only powdered garlic and rice. At Walmart, the authorities found that its ginkgo biloba, a Chinese plant promoted as a memory enhancer, contained little more than powdered radish, houseplants and wheat—despite a claim on the label that the product was wheat- and gluten-free.”
Supplements are not regulated by the Food and Drug Administration because they are not marketed as drugs. According to the Dietary Supplement Health and Education Act of 1994, “The dietary supplement manufacturer is responsible for ensuring that a dietary supplement is safe before it is marketed… Generally, manufacturers do not need to register their products with FDA nor get FDA approval before producing or selling dietary supplements. Manufacturers must make sure that product label information is truthful and not misleading.”
In fact there is no requirement at all that these substances be scientifically tested for safety or efficacy, and many have in fact been proven not to be effective for the conditions they are used. The vitamin and herbal supplement industry is a multi-billion dollar business, and lobbied hard to keep their products from being regulated by the FDA. As a result, the FDA can only step in when something goes wrong, after people have been injured or killed by natural herbs.
That happened in 2004, when the FDA banned ephedra, an herbal remedy used in traditional Chinese medicine. Millions of consumers took the herb assuming it was natural, safe, and effective—until the supplement was linked to over 100 deaths.
The consequences of mislabeled supplements can be severe; in 2010 health guru Gary Null, nutrition author and marketer of dietary supplements including “Gary Null’s Ultimate Power Meal,” claimed that he nearly died after taking his own supplements. Null sued the manufacturer, saying he experienced kidney damage, pain, and fatigue from consuming the Power Meal because the manufacturer put 1,000 times the correct dose of Vitamin D in his product.
Read more at Discovery News
|The female blanket octopus will sadly enough never know the comforts of an actual blanket.|
But roaming the open oceans is a creature that sports a true security blanket: the so-called blanket octopus. Stretched between the cephalopod’s highly elongated arms are vast sheets of flesh, and when the octopus feels threatened, it splays out its arms to deploy a stunning cloak that maybe, just maybe, will convince an encroaching predator to piss off.
Even if that doesn’t do the trick, the octopus’ arms will break off in its enemy’s mouth, like a lizard losing its tail, hopefully allowing the erstwhile prey to beat a retreat. These are invaluable defenses because unlike their cousins, blanket octopuses don’t ever spend time on the seafloor, and thus don’t have the luxury of crevices to squeeze into for protection. And that’s very weird for an octopus.
But perhaps the strangest thing about the blanket octopus has nothing to do with its weaponry or flowing cape. While females can grow to a formidable 6 feet long, males are incredibly hard to find. They’re so small—less than an inch long—that they could fit inside the ladies’ pupils, according to Tom Tregenza, a biologist at the University of Exeter who co-authored a 2002 paper describing the first-ever sighting of a live male blanket octopus. A female blanket octopus can be an astounding 10,000 times heavier than a male, perhaps up to 40,000 times. Indeed, the differences between the two sexes are more extreme than any other animal this size.
But before we dive into that, let’s first talk about one of the gutsiest weaponizations in the animal kingdom. The diminutive males don’t have the flashy flesh blankets of the females, but they can exploit a menace that other creatures, including humans, would be mad to mess with: the infamous Portuguese man o’ war. The blanket octopus is immune to its stings, so a male will just waltz up and snag a tentacle (the man o’ war isn’t actually a jellyfish, but a sort of colony of clones known as a siphonophore). The little male octopus then wields the tentacle like a toxic whip to fend off predators. And that, as biologists say, is legit. Juvenile females also do this, but abandon the strategy as they grow into giants, “because once you get very large, it’s not much of a defense” trying to sting your predator’s mouth, says Tregenza. “If a shark is going to take a big bite out of you, it’s probably not going to worry very much about the peppery taste.”
Physical differences like this are known as sexual dimorphism. You sometimes see it in something like size or ornamentation—the female bird of paradise is positively drab compared to the flamboyant male. But females are typically bigger than males not only because their gametes take up a lot more space than sperm, but because eggs take tremendous energy to produce. And while males can get away with being tiny, the trend tends to reverse itself when males compete fiercely for females. In that case, bigness can be an evolutionary advantage, since the largest males win the right to mate. Thus does the human “dude bro” seem to get bigger and bigger as the years go by.
|I’d be willing to bet that the male blanket octopus has some serious inadequacy issues.|
So the tiny male blanket octopus finds himself floating out there all alone in the vast ocean. He’ll be lucky to find a female, but once he does, he leaves his mate something special to remember him by—like, uh, a limb. “The blanket octopus male puts all the sperm its got into a modified arm,” says Tregenza. “The arm then breaks off and crawls into the female’s mantle cavity.” There, it may even find company: Females can retain the arms of multiple males simultaneously. The male then jets away, though the female isn’t necessarily fertilized just yet. “The female blanket octopus will have the male’s arm inside her,” Tregenza says, “and when she comes to need to fertilize her eggs, she can pull that arm out and squirt the sperm over her eggs like squirting soy sauce onto fried rice.” Thus concludes the greatest analogy in the history of science.
Read more at Wired Science
Mar 19, 2015
Vampire crabs owe their name to their spooky appearance, as they have bright-yellow eyes contrasting sharply with purple or orange abdomens.
People in the aquarium trade have known of the two crab species described in the report for at least a decade, said Peter Ng, a biology professor at the National University of Singapore and an author of the report. Ng said he saw the crabs for the first time in aquaria in Singapore, where the crustaceans were being sold as pets.
The problem for scientists was that it was not clear where the crabs originally came from, which made it difficult for researchers to actually name and describe the traits of the species in the wild.
"For a species to be formally and properly described and named, its provenance should be known," Ng told Live Science. "Of course, it is perfectly legal to name a species without knowing where it comes from, but that would be bad science and irresponsible."
Crab dealers have pointed to a number of possible places of origin for the crabs, from Java to Krakatoa, Borneo, Sulawesi and even New Guinea. But all of those sites were suspicious, Ng said.
With a good deal of detective work, study coauthor Christian Lukhaup, a German carcinologist (crab expert), traced the crabs' origins from dealers in Germany all the way back to Java, Ng said. Lukhaup persuaded businessmen and traders to connect him to the people in Java who were actually collecting the crab. These collectors then passed specimens of the animals on to the researchers.
The two new species have been named Geosesarma dennerle and Geosesarma hagen. There are now 53 species of Geosesarma genus known to science, said Ng, who himself has named 20 of the species. He said he currently has another half a dozen or so newly collected Geosesarma species from Southeast Asia in his lab, and these species still need to be named and described.
"So there are more to come as we explore and discover them," he said.
Read more at Discovery News
Named "Carolina Butcher" (Carnufex carolinensis), the newly discovered toothy beast reveals that predecessors of today's crocodiles -- crocodylomorphs -- were top predators in North America prior to the reign of dinosaurs.
Carolina Butcher, described in the latest issue of the journal Scientific Reports, lived up to its horror movie-style name.
"Carnufex lived in what is now North Carolina around the time the supercontinent Pangea was breaking apart," lead author Lindsay Zanno told Discovery News. "The skull of Carnufex is slender and long-snouted with dozens of blade-like teeth. For all practical purposes, this was an animal skillfully adapted for slicing flesh from the bones of its victims."
Zanno is an assistant research professor at North Carolina State University and director of the Paleontology & Geology Research Laboratory at the North Carolina Museum of Natural Sciences. She and her colleagues recovered the remains of Carolina Butcher from the Pekin Formation in Chatham County, North Carolina. When the crocodylomorph was alive during the beginning of the Late Triassic, this area was a wet and warm equatorial region.
The researchers created a detailed 3-D model of Carolina Butcher's skull using a high-resolution surface scanner to digitize each unearthed fossil from what's left of the animal's head. This high tech model and the croc's other remains suggest that the carnivore was at least 9 feet tall. Because its forelimbs were so short compared to its skull, the researchers suspect that the carnivore walked on two legs a/la T. rex.
The scientists don't yet have hard evidence -- such as stomach contents or unique bite marks on other animal fossils -- indicating what Carolina Butcher hunted. Based on other known animals from this area at the time, however, the scientists believe likely prey candidates were aetosaurs (armored reptiles) and dicynodonts (large-bodied early relatives of mammals). These animals themselves were formidable.
Carolina Butcher was not the only meat-eater around, either.
"The Triassic was a bit of an ecological Twilight Zone: too few plant eaters and an over abundance of predators meant that the hunters often became the hunted," Zanno said.
She explained that other major terrestrial predators roaming around this area in North America at the time were rauisuchids, which had skulls that looked a lot like tyrannosaurs. Phytosaurs, which resembled today's crocodiles but were actually more distant relatives, hunted in the water and sometimes even killed rauisuchids, perhaps when an unlucky one strayed too close.
As time went on, the pileup of predators dramatically changed after a major extinction event occurred.
"By the end of the Late Triassic, all of the large predators on land, except dinosaurs, had been wiped from the face of the planet," Zanno explained. "Scientists aren't yet sure why, but the prevailing hypothesis is that the absence of other competitors gave theropods (carnivorous dinosaurs) a big boost on the Mesozoic playing field."
Smaller ancestors of crocodiles made it through the extinction event, and later on found their ecological niche. They re-evolved into the larger sizes exhibited by crocodiles and alligators today.
Diego Pol of Argentina's Museo Paleontológico Egidio Feruglio also studies early predators. He told Discovery News that Zanno and her team's discovery "fills an important gap in the early evolution of crocs."
Read more at Discovery News
The biblical text's journey was long and circuitous. After its publication in 1677, the book bounced among scholars, landed in Egypt and finally fell into the hands of Micha Shagrir, an Israeli film producer and director. Shagrir died in February, but his family recently donated the text to the University of Haifa in northern Israel, which already has a near-duplicate copy of the rare text in its collection, according to a statement from the university.
The Old Testament is also known as the Tanakh, an acronym that includes the Torah (the five books of Moses), Nevi'im (prophets) and Ketuvim (writings) — or TaNaKh.
However, the newfound Tanakh wouldn't have graced synagogues, said Yossi Ziegler, academic director of the University of Haifa's Younes and Soraya Nazarian Library.
"It is a Tanakh which was produced not for Hebrew readership," Ziegler told Live Science. "It was produced for, I assume, Christian scholars interested in the Hebrew text and wishing to have access to the best version of it."
In the 16th and 17th centuries, a group of Christian theologians in western Europe wanted to read and study the Tanakh in its original Hebrew, as opposed to the vernacular language of their region. "They were keen to learn Hebrew and to have access to the original text, which they used to explain in their text which they couldn't understand," Ziegler said.
David Clodil (1644-1684), a renowned German Lutheran, wrote a commentary for the book, and produced and edited it for his academic audience. Clodil included Hebrew numbers, as well as Arabic numerals, to help his readers navigate the text, Ziegler said.
The title page, in Latin, identified Clodil as "Professor Ordinarius of Oriental Languages and Professor Extra-Ordinarius of Theology at Alma Mater Giessen," said Ziegler, who translated it into English.
The university's library has another, smaller copy of the same Tanakh, but the volumes are slightly different. The library's copy has almost no margins, but the newfound copy has ample space for scholars to write notes in its margins, Ziegler said.
In fact, the donated copy has numerous marginalia scrawled throughout it in German and Latin, and was used by no fewer than 10 different readers in the 17th and 18th centuries, Ziegler said.
"It's a beautiful book — very well preserved," he said. "But we don't know who used it. We don't know who owned it."
Before he passed away, Shagrir decided to donate the Tanakh to the University of Haifa. Ziegler thanked him, and asked Shagrir to share the story of how he came into possession of such a rare book.
The story began in 1977, a month after then-Egyptian President Anwar Sadat visited Israel. Shagrir said that he and a group of Israelis made a secret trip to Egypt, and happened to visit an antique bookstore in Cairo during their stay.
The owner of the store wasn't Egyptian, but Armenian. He recognized Shagrir, and told the filmmaker he admired a film Shagrir had produced about the Armenian genocide.
To show his thanks, the shopkeeper gave Shagrir a wrapped book, and asked him not to open it until he had returned to Israel. Shagrir agreed, and was shocked to find the ancient Tanakh when he opened the package.
Read more at Discovery News
The March 20 total solar eclipse event will be the first since Nov. 3, 2013. The dark umbral shadow cone of the moon will trace a curved path primarily over the North Atlantic and Arctic Oceans, beginning off the southern tip of Greenland and then winding its way counterclockwise to the northeast, passing between Iceland and the United Kingdom.
The shadow will then pass over the Danish-owned Faroe Islands, the sparsely inhabited Norwegian island group of Svalbard and then it will hook counterclockwise toward the northwest, where it leaves the Earth’s surface just short of the North Pole.
If you don't have the chance to see the solar eclipse in person, you can catch it live online as well. The online Slooh Community Observatory will broadcast live views of the solar eclipse through its website Slooh.com, beginning at 4:30 a.m. EDT (0830 GMT).
You can also watch the total solar eclipse webcast on Space.com on March 20, courtesy of Slooh.The Virtual Telescope Project will also air live views of the eclipse through the project's website beginning at 4 a.m. EDT (0800 GMT), and it will also be carried on Space.com if possible.
The Faroes are an island group consisting of 18 major islands with a total area of approximately 540 square miles (1,400 square kilometers) and a population of almost 50,000 people. The islands are rugged and rocky with some low peaks; the coasts are mostly cliffs.
The point of greatest eclipse occurs about 162 miles (260 km) north of the Faroes, in the Norwegian Sea. By the standards of most eclipses, the moon’s shadow projected onto the Earth’s surface for this event will resemble a huge ellipse of darkness measuring about 288 miles (463 km) wide by 93 miles (150 km) long.
These unusual dimensions can be attributed in part to the fact that about 13.5 hours earlier, the moon will arrive at that point in its orbit closest to Earth (perigee), 222,192 miles (357,584 km) away. And because the shadow is passing over the Arctic, it will strike the Earth at a very oblique angle, resulting in its distinct elliptical shape. (Solar eclipse enthusiast Michael Zeller created an interesting animation showing the eclipse's path.)
About a half hour after leaving the Faroes, the shadow makes its next — and final — landfall at Svalbard, a Norwegian archipelago in the Arctic Ocean. Situated north of mainland Europe, it is about midway between continental Norway and the North Pole. The largest island is Spitsbergen, followed by Nordaustlandet and Edgeøya. Other than the research stations located at Alert, Nunavut and Nord, Greenland, Svalbard is the northernmost place in the world with a permanent population. Based on the most recent census, only 2,642 people live there.
The town of Barentsburg, on Spitsbergen (one of the principal islands of Svalbard) will witness 2 minutes 20 seconds of total eclipse beginning at 1011 GMT with the sun standing a scant 11 degrees. Since your clenched fist measures roughly 10 degrees across, this means that the totally eclipsed sun will lie very low — only “one fist” above the south-southeast horizon.
Unfortunately, the typical weather pattern for this part of the globe as the winter transitions to spring is not very favorable. The chances for a sky with clear-to-scattered clouds averages only 20.4 percent for the Faroe Islands and a little better at 34.6 percent for Spitsbergen. But sometimes a place with poor weather prospects can get lucky.
An artifact of the total eclipse will be a large partial eclipse of the sun that will be visible across all of Europe, northern Africa and much of northern Asia. Depending on where you are in Europe, you will see anywhere from roughly 50 to nearly 99 percent of the sun’s diameter eclipsed by the moon.
In those areas where 80 percent or greater coverage is to occur, a weird "counterfeit twilight" will happen for a few minutes around the time of maximum eclipse. Those areas with an eclipse magnitude greater than 90 percent include Ireland, much of Great Britain (London gets 87 percent), Scotland, Norway, central and northern Sweden, northern Finland and Iceland (97 percent coverage for Reykjavik).
Read more at Discovery News
The comet, called 67P/Churyumov–Gerasimenko, or 67P for short, is a transplant from the Kuiper belt, a region beyond Pluto littered with icy bodies left over from the formation of the solar system some 4.6 billion years ago.
Rosetta arrived at the comet in August 2014 and three months later released a companion lander named Philea for additional studies. Philea touched down, but then bounced several times before coming to rest sideways wedged in a hole or jammed against a cliff wall.
The lander was able to run through a preprogrammed series of initial experiments before losing power. Scientists hope to regain contact with the probe in the next few months so it can resume its studies, the first to be conducted on the surface of a comet.
During its brief mission, Philae collected some key data, including images that show the entire comet may be made of pebbles, scientists said at the Lunar and Planetary Science Conference in Houston this week.
If confirmed, scientists will have to rethink how pebbles as big as some seen on 67P could form so far from the sun.
“The pebble accretion is kind of a new idea,” University of Washington astronomer Donald Brownlee told Discovery News.
The theory is that motions of gas can effectively transport and trap medium-sized pebbles, which in turn attract more gas. “It’s like a magnet effect,” Brownlee said.
“The cool thing is then accretion speeds are basically zilch. Instead of (objects) whamming in at a kilometer-per-second, or a fraction of a kilometer-per-second, they can just drift around at meters-per-second. They’re still orbiting the sun, but relative to each other, the speeds can be very low,” he said.
Rosetta might be the first body to provide proof of the idea, added Brownlee, who is not involved with the mission.
Scientists have had previous hints that comets may be piles of pebbles. NASA’s Stardust spacecraft flew past a comet called Wild-2 (pronounced “Vilt-2”) in 2004 and later returned samples back to Earth.
“On Stardust, we did see some blocks that were clearly stronger than their surrounding material, but our resolution was 12 meters,” said Brownlee, who was lead scientist on the mission.
“We thought the surrounding material was just ablating away and leaving their original blocks. Rosetta is seeing huge numbers of these things, so my guess is those are original accreted materials ... debris that was out there in the Kuiper belt that went in to form the comet. The fact that they survived means they couldn't have been zipping in at kilometers-per-second speeds,” he said.
Scientists on the Rosetta and Philea missions have mapped several hundred of these objects.
“We can’t tell yet if these are really all throughout the interior of the comet,” astronomer Holger Sierks, with the Max Planck Institute for Solar System Research in Germany, told Discovery News.
Read more at Discovery News
Mar 18, 2015
City officials there have decided to close off a portion of road to vehicle traffic, to enable the protected Jefferson salamander to cross without meeting an automotive demise.
The road, Stauffer Drive, is a key crossing point for the declining amphibians, which live on either side of the street and cross it each spring to find small ponds that appear after snow has melted.
City officials told CBC News it's the fourth time they have closed the road, which will remain automobile-free until May 1.
Jefferson salamanders can be found from the U.S. Northeast through southern and eastern Ontario and southwestern Quebec. They're anywhere from 4 to 7 inches long (11 to 18 centimeters) and are black, brown or dark gray.
Being mole salamanders, Jeffersons are accomplished burrowers, and they breed in early spring, as soon as the snow melts. In Kitchener, they won't have to look both ways before crossing the street.
From Discovery News
In response to their diet, they optimise the size, strength and stickiness of their webs for catching whatever prey is around, say researchers today in the Royal Society journal Open Science.
"When a fly or cricket hits a spider web, the web has to intercept the prey and hold it there until the spider comes and feeds," says Dr Sean Blamire, an evolutionary biologist at the University of New South Wales.
But different prey strike the web with different forces and vibrate it in different ways in their attempt to escape.
"Crickets strike the web with more force and kick off against the web, causing pulse-like vibrations," says Blamires. "Flies buzz rather than pulse and put less stress on the web."
Given the cost of producing strong webs, spiders have to design their web to account for this so they don't invest in silk when they don't need to, says Blamires.
Previous research has suggested that spiders on different diets have different webs, but the question is what aspect of the prey is giving spiders the information they need to customise their web for different prey?
Blamires and colleagues investigated two possible cues influencing web design, in a complex experiment that involved feeding orb-weaving spiders Nephilia pilipes flies and crickets.
The researchers looked at the impact of different vibrations given off by prey attempting to escape the web.
They then looked at the impact of different nutrients extracted by spiders from the prey.
Blamires and colleagues found that it was these nutrients that were the main driver of web architecture.
He says this makes sense because spiders need to make sure they have enough protein to keep building webs.
Read more at Discovery News
Researchers said they were "convinced" that among crumbling remains in a crypt they had found Cervantes, hailed by academics as the father of the modern novel.
Forensic anthropologist Francisco Etxeberria said that after a year-long search his team had positively identified "some fragments" of the author who died in April 1616, the same month as William Shakespeare.
Don Quixote -- the delusional country gentleman who sets out to right wrongs as a self-styled knight -- had a far-reaching impact on world literature, academics say.
Though there is no genetic proof of the find at this stage, Etxeberria's team of anthropologists and archaeologists said they were confident of the claim on the basis of documentary research.
They based their findings on fragments found underground in the crypt of a church in the Convent of the Barefoot Trinitarians in central Madrid, Etxeberria said.
Archeologist Almudena Garcia-Rubio said there was "no confirmed genetic identification" of the human remains.
But Etxeberria said: "We are convinced that we have among these fragments something of Cervantes."
Cervantes is recorded as having been buried at the convent's chapel a day after his recorded death on April 22, 1616, but the exact whereabouts of his grave were unknown.
Etxeberria's team launched in April 2014 the first significant search for the remains of the greatest writer of the Spanish Golden Age.
They used infrared cameras, 3D scanners and ground-penetrating radar to identify spots where remains could be stored.
Born near Madrid in 1547, Cervantes has been dubbed the father of the modern novel for "The Ingenious Gentleman Don Quixote of La Mancha", published in two parts in 1605 and 1615.
His influence has been so great that Spanish is often referred to as "the language of Cervantes."
But his impact went beyond Spanish, particularly in the development of the novel as an art form.
The proverbial phrase "tilting at windmills" -- a well-meaning, misguided bid to vanquish imaginary enemies -- also originated from Don Quixote's adventures.
Cervantes spent his last years in a Madrid neighbourhood now called the Literary District in memory of him and his 17th century rivals Lope de Vega, Francis de Quevedo and Luis de Gongora.
"This a very important day for Spain and for our culture," said the mayor of Madrid, Ana Botella.
Culture Minister Jose Ignacio Wert hailed the discovery, saying its announcement coincided with celebrations planned this year for the fourth centenary of the publication of the second volume of Don Quixote.
"From a purely literary point of view, this will not change much," said Jean Canavaggio, a biographer of Cervantes at the University of Paris-Nanterre, of Tuesday's announcement.
"But there will be crowds of tourists flocking to the Trinitarians convent. That will be a source of revenue for Madrid."
Read more at Discovery News
During the ceremony, the king’s bones were laid out as if articulated in a lead casket along with bone fragments and scientific samples wrapped up in linen bags.The lead casket had been placed inside a 5-foot, 10-inch oak coffin built by Michael Ibsen, a descendant of Richard III’s elder sister, Anne of York.
“In order to pack the bones into the lead lined coffin, natural materials sourced from the British Isles which would have existed in the medieval period were used,” the University of Leicester said in a statement. “A combination of washed natural woolen fleece, wadding and unbleached linen were used for the layers of packing."
A rosary was also placed in the inner coffin and the final layer was an embroidered piece of Irish linen.
Once the lead casket was sealed, Ibsen fixed the lid of the outer coffin in position.
The ceremony -- carried ahead of the king’s reburial at Leicester’s Cathedral on March 26 -- was witnessed by representatives from the university, Leicester Cathedral, the City Council, the Richard III Society, an independent witness and relatives of Richard III who donated their DNA as part of the identification process.
The skeleton was found in 2012 beneath a car park. Mitochondrial DNA showed a match between Richard and two of his living relatives, confirming that the bones are indeed those of the king.
Further analysis shed light on his diet and disease, and even provided a blow-by-blow account of his final moments.
Depicted by William Shakespeare as a bloodthirsty usurper, Richard ruled England from 1483 to 1485. He was killed in 1485 in the Battle of Bosworth, which was the last act of the decades-long fight over the throne known as War of the Roses. England’s last king to die in battle, he was defeated by Henry Tudor, who became King Henry VII.
Read more at Discovery News
Scientists combined data collected by the Kepler telescope with computer models replicating preferential structures of planetary systems to calculate the likelihood that planets would end up in life-friendly orbits — those properly distanced from their parent stars for liquid surface water.
The results of the study, published in the Monthly Notices of the Royal Astronomical Society, indicate that billions of stars in the Milky Way have planets in so-called "habital zones" suitable for liquid water – and possibly life.
The study identifies candidate planetary systems properly positioned for follow-up studies to confirm suspect sister planets in habitable zones.
"If they are found, it is an indication that the theory stands up," astronomer Steffen Kjær Jacobsen, with the Niels Bohr Institute at the University of Copenhagen, said in a statement.
From Discovery News
Mar 17, 2015
Initially triggered by the impact of a coronal mass ejection (CME) hitting our planet’s magnetosphere, a relatively mild geomagnetic storm erupted at around 04:30 UT (12:30 a.m. EDT), but it has since ramped-up to an impressive G4-class geomagnetic storm, priming high latitudes for some bright auroral displays.
When strong auroral activity started brightening the skies early this morning over Alaska, speaking with Spaceweather.com photographer Marketa Murray said: “The auroras were insane. I have never seen anything like this.”
Launched from the sun on Sunday, a large Earth-directed CME has reached Earth faster than expected. We’ve seen an uptick in solar activity in recent days, culminating in the first X-class flare of 2015 last week. But the impact of this CME has taken space weather scientists by surprise, an indication that the CME was “geoeffective.”
Wrapped in a powerful magnetic field, CMEs consist of huge bubbles of energized gas from the sun’s superheated corona (the solar atmosphere). The speed at which the CME travels into interplanetary space and the alighnment of its magnetic field can severely influence that CME’s impact on Earth’s magnetic field.
Our planet has a global magnetic field called the magnetosphere, so should a CME hit the magnetosphere at just the right alignment, the CME’s magnetic field can reconnect, causing intense magnetic disruption, injecting the magnetosphere with huge quantities of plasma from the sun. In this situation, the CME is said to be “geoeffective” and the resulting geomagnetic storm can be extreme.
Today’s storm is so intense that it far overshadows anything that has come before it in our sun’s current solar cycle. Approximately every 11 years, the sun waxes and wanes in magnetic activity, culminating in solar maximum, when the solar magnetic field is so stressed that flares and CMEs are commonplace. Although the sun is currently declining in activity from maximum that was predicted to have peaked in 2013, it goes to show that Solar Cycle 24 hasn’t finished with us quite yet.
Read more at Discovery News
Featuring a pink-violet colored stone with an inscription that reads “for Allah” or “to Allah,” the silver ring was found during the 1872-1895 excavations of grave fields at the Viking age trading center of Birka, some 15.5 miles west of Stockholm.
It was recovered from a rectangular wooden coffin along with jewelry, brooches and remains of clothes. Although the skeleton was completely decomposed, the objects indicated it was a female burial dating to about 850 A.D.
The ring was cataloged at the Swedish History Museum in Stockholm as a signet ring consisting of gilded silver set with an amethyst inscribed with the word “Allah” in Arabic Kufic writing.
The object attracted the attention of an international team of researchers led by biophysicist Sebastian Wärmländer of Stockholm University.
“It’s the only ring with an Arabic inscription found in Scandinavia. We have a few other Arabic-style rings, but without inscriptions,” Wärmländer told Discovery News.
Using a scanning electron microscope, the researchers discovered that the museum description wasn’t entirely correct.
“Our analysis shows that the studied ring consists of a high quality (94.5 percent) non-gilded silver alloy, set with a stone of colored soda-lime glass with an Arabic inscription reading some version of the word Allah,” Wärmländer and colleagues wrote in the journal Scanning.
Although the stone wasn’t an amethyst, as long presumed, it wasn’t necessarily a material of lower value.
“Colored glass was an exotic material in Viking Age Scandinavia,” Wärmländer said.
A closer inspection revealed the glass was engraved with early Kufic characters, consistent with the grave at Birka dating to around 850 A.D.
The researchers interpreted the inscription as “il-la-lah,” meaning “For/To Allah.” Alternative interpretations of the engraving are possible, and the letters could also be read as “INs…LLH” meaning “Inshallah” (God-willing).
“Most likely, we will never know the exact meaning behind the inscription, or where and why it was done,” the researchers wrote.
“For the present investigation, it is enough to note that its Arabic-Islamic nature clearly links the ring and the stone to the cultural sphere of the Caliphate,” they added.
Most interestingly, Wärmländer and colleagues noted the ring body is in mint condition.
“On this ring the filing marks are still present on the metal surface. This shows the jewel has never been much used, and indicates that it did not have many owners,” Wärmländer said.
In other words, the ring did not accidentally end up in Birka after being traded or exchanged between many different people.
“Instead, it must have passed from the Islamic silversmith who made it to the woman buried at Birka with few, if any, owners in between,” Wärmländer said.
Read more at Discovery News
Hang Son Doong from Ryan Deboodt on Vimeo.
An underground river river eroded massive amounts of limestone from underneath a mountain, which collapsed creating massive skylights. The cave was named the largest in the world after a 2009 expedition to survey it by the British Cave Research Association.
From Discovery News
The whale (Ziphiidae) lived when the East African plateau was substantially lower and covered by dense forests, the researchers said. Scientists have long tried to figure out when the uplift occurred, because when it did, the moisture from the Indian Ocean could no longer reach the trees and vegetation, and the area turned into a savannah, research suggests.
Extinct ancestors to modern humans may have lived in trees in East Africa, but after the area turned into grassland, these early humans gradually began walking on two feet, researchers suggest.
"It's more or less the story about the bipedalism," said study researcher Henry Wichura, a postdoctoral candidate in geoscience at University of Potsdam in Germany.
But the timing of the East African plateau uplift has eluded scientists. The whale fossil helps researchers get closer to that date, which likely occurred sometime between 17 million and 13.5 million years ago, according to the new study.
The story of the whale skull is one of rediscovery. Researchers originally found the fossil in 1964, but didn't publish a study on it until 1975. Then, they misplaced the skull until 2011.
The skull is the oldest known fossil of a beaked whale, and it confounded researchers at first. Beaked whales are deep divers that live in the ocean, but the fossil was found 460 miles (740 kilometers) inland from the present-day East African coast, and at an elevation of 2,100 feet (640 meters).
Perhaps the 23-foot-long (7 m) whale used to live in the Indian Ocean, but mistakenly strayed into a river that led it into modern-day Kenya, the study researchers said.
"We came to the idea that it used a large river system, because the whale had been found in lake sediments which are [mixed with] river sediments," Wichura said. "So we can say that it died in a kind of river-lake environment."
But the fossil sat unstudied for nearly 40 years, until researchers rediscovered it at Harvard University. (Interestingly, a curator found the fossil in the former office of renowned paleontologist Stephen Jay Gould. At the time, the university was using Gould's office for temporary storage during a remodel, according to the study.)
Once recovered, the skull helped Wichura and his colleagues date the East African plateau's uplift. They wondered how low the East African plateau was before the region's topography changed, so they searched for other instances of whales getting lost in rivers. For instance, one whale became stranded in the Thames River in 2006, and killer whales have swum into the Columbia River in the Pacific Northwest of the United States.
The scientists took the grade of the steepest river from case reports, and applied it to the prehistoric river used by the whale. So, if the ancient river rose at 2.5 inches a mile (4 centimeters per km) from the coast, the East African plateau was between 79 feet and 121 feet high (24 m and 37 m) at the time the whale lost its way and died. (The difference in height takes into account the different routes the whale may have taken to swim inland from the Indian Ocean.)
Considering that the plateau is now about 2,034 feet (620 m) tall, the northern part of the Eastern African plateau must have been uplifted by about 1,925 feet (590 m) over the past 17 million years, the researchers determined.
Furthermore, Wichura found that at 13.5 million years ago, part of the Eastern African plateau uplift had already begun, putting a bookend on when the uplift started. (He noted that the uplift happened because of mantle plumes, hot material that rises through the Earth's mantle and pushes up against the crust.)
Without the rediscovered skull, it would have been difficult to help date the uplift, he said.
Read more at Discovery News
The explosion of GK Persei was triggered by the buildup of hot plasma on the surface of a white dwarf star. The small, dense object had been siphoning the gas from a binary partner. When the plasma reached a critical mass, a powerful thermonuclear explosion ripped through the upper layers of the white dwarf.
This explosion, however, did not destroy the white dwarf and was therefore not a “supernova;” it was a “classical nova.”
The result of a classical nova is a rapidly brightening orb of hot gas and interstellar shock waves that leave the progenitor star intact — a mini-supernova of sorts. Although novae do not create the heavy elements that supernovae are known to generate, seeding the galaxy with elements like iron, calcium and oxygen, novae like GK Persei can still have dramatic effects on surrounding space.
Now, NASA’s Chandra X-ray Observatory has gathered the results of observations it carried out in February 2000 and then again in November 2013. Over a century later, GK Persei still resembles an expanding mess of hot material, but by having two sets of observations 13 years apart, short-term changes in the nova debris can be seen.
Chandra has clocked the clumps of gas blasting away from the point of detonation at 700,000 miles per hour — meaning the blast wave has traveled 90 billion miles (nearly 1,000 astronomical units) over those 13 years.
Over the same period, the luminosity of the material has obviously decreased (by 40 percent), but of particular interest is the temperature of the surrounding interstellar gases — the temperature has remained constant, which is peculiar.
Read more at Discovery News
Mar 16, 2015
According to NBC News, the Crown Prince of Dubai asked Freedom Conservation if it would visit his city and help address urban wildlife conservation. Within a few months' planning, camera technicians and falconer Jacques-Olivier Travers, Darshan's trainer, were able to bring about the footage above.
From Discovery News
Written in Greek on a piece of pottery, the receipt states that a person (the name is unreadable) and his friends paid a land-transfer tax that came to 75 "talents" (a unit of currency), with a 15-talent charge added on. The tax was paid in coins and was delivered to a public bank in a city called Diospolis Magna (also known as Luxor or Thebes).
But just how much was 90 talents worth in ancient Egypt?
"It's an incredibly large sum of money," said Brice Jones, a Ph.D. student at Concordia University in Montreal, who translated the text. "These Egyptians were most likely very wealthy."
The receipt has a date on it that corresponds to July 22, 98 B.C. Paper money didn't exist at that time, and no coin was worth anywhere near one talent, the researchers said. Instead people made up the sum using coins that were worth varying amounts of drachma.
One talent equaled 6,000 drachma, so 90 talents totaled 540,000 drachma, researchers say. For comparison, an unskilled worker at that time would have made only about 18,000 drachmaa year said Catharine Lorber, an independent scholar who has published numerous journal articleson Egyptian coins.
In 98 B.C., the highest-denomination coin was probably worth only 40 drachms Lorber said. This made for a truly back-breaking tax load.
It "would have taken 150 of these coins to make a talent, and 13,500 of them to equal 90 talents," Lorber told Live Science in an email. "The coins in question weigh, on average, 8 grams [0.3 ounces], so the total payment of 90 talents probably had a weight in excess of 100 kilograms [220 lbs.]."
What likely happened is that one or more tax farmers (people charged with collecting certain types of taxes) got 90 talents' worth of coins from the individuals paying this tax, the researchers said. These tax farmers then would have had to physically bring the cash into the bank. Lorber noted that the Ptolemies (the ruling dynasty in Egypt at the time) required tax farmers to absorb the cost of transport and handling. In cases where tax farmers had to bring in a big load, "it was packed in baskets and carried by donkeys," Lorber said.
The 15-talent surcharge, which was added on to the 75-talent tax bill, suggests that the people paying this land-transfer tax were penalized for not paying part of the bill in silver — a charge that was called the "allage," Lorber said.
"This was an exchange fee imposed on bronze currency when it was used to pay an obligation that legally should have been paid in silver," Lorber said. "This system was maintained even in periods when silver coinage was scarcely available."
Today, people often complain about political gridlock and conflict on Capitol Hill, but this is likely nothing compared to the drama and infighting among Egypt's rulers around the time this newly translated bill was paid.
Read more at Discovery News
Researchers recently discovered smooth glass spheres in ash from explosive volcanic eruptions. Kimberly Genareau, a volcanologist at the University of Alabama, first spotted the orbs while scanning ash from Alaska's 2009 Mount Redoubt eruption with a powerful microscope. She also found them in ash from Iceland's 2010 Eyjafjallajökull eruption.
Both volcanoes blasted out billowing ash clouds that triggered spectacular displays of volcanic lightning. Inside these murky clouds, ash particles rub together, generating static electricity that discharges as lightning.
Genareau and her colleagues said they think the lightning displays forged the glass balls from particles of volcanic glass. Their findings were published Feb. 27 in the journal Geology.
Volcanoes spit out jagged glass shards during eruptions, along with sharp scraps of rocks and minerals. But lightning within the ash cloud can heat the air to 54,000 degrees Fahrenheit (30,000 degrees Celsius) for a few millionths of a second, melting the glass particles. These molten droplets then form into balls as they fall through the air, Genareau said.
Researchers previously knew that volcanic eruptions could produce glass, but the new findings show how that glass can be made into spheres.
"You don't need volcanic lightning to make glass [in ash], just to get that unusual shape," Genareau told Live Science.
The round spherules from Mount Redoubt and Eyjafjallajökull are only 50 microns across (1/25,000th of an inch), hundreds of times smaller than the spherules that can be ejected during meteorite impacts. Fountaining lava caught by the wind can also form such glass spherules, called Pele's tears.
Some of the glass spherules examined in the study were as smooth as crystal balls, but others were hazed by cracks and pits that may have formed when water expanded into steam as the glass melted.
The research team is planning further studies into how and why the spherules formed. For instance, the scientists verified that a violent shock can produce glass spheres in ash when they found a version of the tiny balls in ash left over from experiments by researchers at the University of Canterbury in New Zealand. In the experiments, the Canterbury researchers, who are also co-authors on the new findings, zapped artificial ash to investigate how volcanic ash disrupts high-voltage insulators. Their tests were similar to lightning discharges inside an ash cloud, Genareau said.
Now, after studying samples from several eruptions, the researchers suspect that it is the size of the ash particles that determines whether the glass spheres appear after volcanic lightning strikes, Genareau said. All the spherules found so far are about 50 microns or smaller in size, she said. Larger ash fragments were partially melted, but didn't completely transform into spherical shapes.
Genareau said she hopes that the new discovery will spark a search for similar spheres in older ash deposits, which could provide new clues about where and when volcanic lightning strikes.
Read more at Discovery News
In recent years, however, astronomers have discovered that ring systems aren’t exclusive to the gas giants. In 2011, a small icy minor body in the outer solar system was also discovered to have rings. Chariklo is a centaur, an asteroid-comet hybrid orbiting the sun in a region between Jupiter and Pluto, and its rings were discovered when the object drifted in front of a bright star — an event known as a stellar occultation.
Now a second centaur called Chiron as been discovered to also have rings, revealing that far from being a frozen and inactive subclass of solar system bodies, centaurs may be a lot more lively than thought.
“It’s interesting, because Chiron is a centaur — part of that middle section of the solar system, between Jupiter and Pluto, where we originally weren’t thinking things would be active, but it’s turning out things are quite active,” said Amanda Bosh, of Massachusetts Institute of Technology (MIT) in Cambridge, Mass.
First discovered in 1977, it became apparent that centaurs were, on the whole, fairly dormant. Like their mythological counterpart — which is part man, part animal — celestial centaurs possess qualities of comets and asteroids. They are undoubtedly rocky, dusty objects, but in the 1980′s astronomers noted comet-like activity on the large centaur Chiron.
Since then, brightening events have been spotted on Chiron, linked to jets of material being ejected from the surface by ices being slowly heated by the dim sunlight, subliming vapor into space.
In the mid-1990′s, James Elliot, who was professor of planetary astronomy and physics at MIT at the time, was able to watch a stellar occultation of Chiron and noted its size (approximately 150 miles wide) and discovered evidence for the jets of vapor and dust.
Now, using two powerful telescopes on Hawaii (NASA’s Infrared Telescope Facility on Mauna Kea and the Las Cumbres Observatory Global Telescope Network at Haleakala), Bosh’s team was able to precisely measure another occultation event in 2011, revealing even more detail in Chiron and the space surrounding it. Their reseach has been published in the journal Icarus.
“There’s an aspect of serendipity to these observations,” said Bosh. “We need a certain amount of luck, waiting for Chiron to pass in front of a star that is bright enough. Chiron itself is small enough that the event is very short; if you blink, you might miss it.”
After analysis of these occulation data, the researchers revealed a surprise — two sharp, symmetrical features were detected before and after the few minutes that Chiron blocked the light of the distant star. These features could be interpreted as a ring system, two bands 3 and 7 kilometers wide with a radius of 300 kilometers from the center of the centaur, adding detail to Elliot’s original observations in the 1990′s.
Read more at Discovery News
Mar 15, 2015
From March through early April, about 600,000 sandhill cranes -- nearly 90 percent of the world’s total sandhill population -- will make a stop at the Nebraskan river, something of a pit stop on the “Central Flyway,” their path to breeding grounds in Canada, Alaska, and as far away as Siberia.
“It’s America’s greatest migration,” Taddicken told FoxNews.com. “Cranes are revered around the world. The Japanese use them for wedding ceremonies, for instance. People have a special connection to the cranes, and just to see this much life all over the place at one time really touches people.”
The scene along the Platte is a sea of life. Since, just as the cranes congregate, so do people across the spectrum of cultures and walks of life. Taddicken has a particularly close view of the spectacle.
The Rowe Sanctuary works with other local groups to conserve the cranes’ roosting habitat as well as protect the nesting habitat for interior least terns and piping plovers, and its offices are situated mere feet from the riverside view.
People from about 54 different countries and all 50 states come to Nebraska to view the birds that fly to Nebraska from Texas, Oklahoma, Arizona, and Mexico, Taddicken said. The cranes visit the site to store up on fat reserves before they make the trek up north for mating season.
Audubon’s conservation work is crucial in maintaining this particular bird population, Taddicken said. Audubon maintains 2,400 acres of land, doing what they can to mitigate damage caused by man-made water regulation — the river has lost about 70 percent of its flow over the past century due to reduced Coloradan snowmelt and human diversions in its path.
Taddicken said that his organization works in concert with other groups on the Platte River Recovery Implementation Program, which is a collaboration between Colorado, Wyoming, Nebraska, and the Department of the Interior to conserve the 310-mile-long river.
Just as the river itself is crucial to the economy and way of life of the people who live alongside it, the crane migration is a major boon to Nebraska, and the small city of Kearney. Migration-watchers bring in around $10 million in annual revenue.
“The first time I encountered it, I was blown away by the magnificence of the spectacle. One time a lady kind of berated me about the fact that I said it was going to be ‘life changing.’ She didn’t think it could ever be that impressive,” he said.
“After spending some time out there, she came back and apologized. She’s now been a volunteer with us every year for the past 12 years.”
This year, the migration peak is about one week off schedule. Taddicken said that next week should see the annual bird meeting at its height.
What strikes Taddicken most is the sound. He said that at one time, you can stare out and see up to 100,000 cranes massing together, “speaking” with one another. Their collective sounds can be heard from a mile away.
Read more at Discovery News
|An acorn-eating island scrub jay. Another population of the species specializes in attacking pine cones, and accordingly has a differently shaped bill.|
As she gathered more and more data on different populations of the birds around the island, Langin had a revelation: The birds, members of one single species, had split into two varieties in different habitats. Island scrub jays living in oak forests have shorter bills, good for cracking acorns. Their counterparts in pine forests have longer bills, which seem better adapted to prying open pine cones. That may not appear to be something you’d consider a “revelation,” but it really is—if you believe in evolution. Ever since Darwin and his famous finches, biologists have thought that in order for a species to diverge into two new species, the two populations had to be physically isolated. Those finches, for instance, each live on a different Galapagos island, where their special circumstances have resulted in specialized bill shapes. Yet the two varieties of island scrub jay (they haven’t technically speciated—yet) live on the same tiny island. If they wanted to meet each other for a brunch of acorns and/or pine nuts and perhaps later some mating, they could just fly right over.
This is very, very weird. It’s an affront to a sacred tenet of evolution you probably learned in school: Isolation drives speciation. Well, speciation can also come about in a broadly distributed population, with individuals at one end evolving differently than individuals at the other, but nothing kicks evolution into overdrive quite like separation. Without it, two varieties should regularly breed and homogenize, canceling out something like different bill shapes (though rarely the two types of island scrub jay will in fact interbreed). And the island scrub jay isn’t alone in its evolutionary bizarreness. In the past decade, scientists have found more and more species that have diverged without isolation. Langin’s discovery with island scrub jays, published last week in the journal Evolution, is perhaps the most dramatic illustration of this yet.
I Say Species, You Say Specious
It’s probably a good idea to take a moment and talk about what exactly a species is. The problem is, it’s hard to say. A species is supposed to be a group of organisms that look similar and can exchange genes by breeding (a handful, though, reproduce asexually). Yet some species can mate with each other and produce offspring, hybrids, and while most of the time they’re sterile, two different species can also come together to produce fertile offspring that can form a new species. So…it’s complicated. Nature doesn’t give a damn about our penchant for classification.
What is clear is that speciation has produced the incredible diversity of life on Earth, and the engine of speciation is reproductive isolation. You can have an island that gets separated from the mainland by rising sea levels, stranding its wildlife to uniquely evolve. Or a volcano can erupt into an island and creatures can float or fly there, as is the case with Hawaii. On the mainland, a new mountain chain can sprout or a river can emerge, splitting a population in two. Thus isolated, the two populations may split into two distinct species adapting to their environment, and those two species may split into two more species, and so on, growing Earth’s enormous tree of life.
|An oak variety of island scrub jay.|
|Santa Cruz Island|
It’s pretty sensational stuff, so sensational that more than a handful of scientists were skeptical of Langin’s claims—initially, at least. “I had one come up to me after a talk I gave in Vancouver, and he said, ‘Katie, I finally believe you!’”
Divergence Without Geographic Isolation: So Hot Right Now
That skeptic was John Fitzpatrick, director of the Cornell Lab of Ornithology, who also studies jays. The fact that Langin’s jays are “literally adjoining one another and presumably even dispersing to one another’s places just seemed farfetched, frankly,” he says. “It seemed that that would be ecological speciation that’s never been demonstrated in birds. So I basically said to Katie, ‘I think you’re barking up a tree that’s pretty scary for a Ph.D. thesis.’”
“But Katie’s nothing if she isn’t persistent and hardworking,” Fitzpatrick adds. “She really has shown a remarkable pattern out there that does make evolutionary sense. It makes ecological sense. But it’s just surprising to be seeing it in action at the scale as tiny and close-knit as the Santa Cruz Island populations are.”
It makes sense because this kind of divergence has been observed in other species. Fitzpatrick says scientists have been talking about speciation without isolation since the 1970s, but for a while there biologists struggled to find many examples out there in nature. Now that seems to be changing. “Within the last decade an increasing number of studies, not just with birds but in fact more so with insects and other invertebrates, show that under certain fairly stringent conditions, this genetic separation can happen even without physical isolation,” Fitzpatrick says.
Take, for example, the apple maggot fly in the Northeast US. It feeds on the hawthorn tree, but when Europeans showed up with apple trees, some of the flies switched to feeding on those. Two different populations then emerged, each focusing on a different kind of tree, even though they all live in the same neighborhood. And they could well be on their way to becoming separate species.
|The pine-loving variety of island scrub jay.|
Read more at Wired Science