With only teeth to go on, scientists have reportedly identified a giant panda ancestor: A. beatrix. // Illustration courtesy José Antonio Peñas, SINC
Christine Dell’Amore
for National Geographic News
Published May 14, 2012
A prehistoric relative of the giant panda has been discovered in Spain, a new study says—which suggests that the charismatic Chinese bears might have originated in Europe.
The 11-million-year-old species, dubbed Agriarctos beatrix, lived in humid forests in what’s now Spain, according to scientists who recently found the animal’s fossil teeth near the city of Zaragoza.
The teeth give paleontologists a lot of information about a species, according to study leader Juan Abella, a paleobiologist at the Museo Nacional de Ciencias Naturales in Madrid, Spain.
“For example, all bear [teeth] have a series of characters that tell us that they are bears. And the same thing happens with dogs, cats, deer, or other vertebrate groups,” Abella said via email.
After analyzing the fossil teeth, he added, the researchers “concluded that they belong to the bear family, and more precisely to the giant panda’s subfamily.”
And the subfamily resemblance may have been striking—Abella and colleagues speculate that the bear had panda-like patterns, because most existing species in the family also have the characteristic dark and white patches.
New Bear Points to European Panda Origins?
But A. beatrix was not your average bear.
For one thing, the 130-pound (60-kilogram) animal was even smaller the smallest modern-day bear species, the sun bear—so it probably wasn’t exactly the top hunter of prehistoric Europe.
Like current pandas and small bears, the newfound species may have scrambled up trees to escape big predators of the day, such as bear dogs—extinct, doglike carnivores—and saber-toothed, feline-like creatures called Barbourofelidae, the team speculated.
For another thing, A. beatrix is the oldest known species in the subfamily Ailuropodinae, which includes the giant panda.
“Therefore, the origin of this group is not located in China, where the [giant panda] species lives, but in the warm and humid regions of [southwestern] Europe,” Abella said.
But Blaine Schubert, a paleontologist at East Tennessee State University who has studied prehistoric bears, said such a claim “seems fairly speculative.”
The new study “doesn’t say that this is evidence that panda bears may have originated in Europe,” said Schubert, who was not involved in the study.
“Further, even if this new fossil is a relative of modern pandas, it doesn’t mean that pandas originated there. I would not suggest this based on the evidence and I wouldn’t want to make a claim like that without a lot more evidence.”
Giant Panda Ancestors Trekked to China?
If giant panda ancestors did come from Spain, how did they get to China?
Previous research suggests bears generally are “able to disperse quite easily if the environmental conditions were favorable for them,” Abella said. At the time, southwestern Europe was warm and humid—good conditions for starting out, he said.
The bears also likely migrated mostly on land—one potential barrier, an ancient European sea called Parathetys, was already shrinking by A. beatrix’s time, he said.
As for whether A. beatrix itself made it to China, “we don’t really know. But no fossil remains of this species have been found outside Spain.”
Abella next hopes to unearth an A. beatrix skeleton, which would reveal more about the how the bear lived and moved. (See: “Ancient Bear DNA Mapped—A First for Extinct Species.”)
It’s unknown whether such a skeleton exists, but the team working with the Institut Català de Paleontologia in Barcelona to excavate “very rich and interesting” fossil beds, Abella said. These fossil beds could conceivably contain A. beatrix remains, since the beds are about as old as those A. beatrix teeth.
“Until we [find] more remains of this species,” he said, “we can not give much more information.”
The panda-relative study was published in the most recent edition of the journal Estudios Geológicos.
(Source: National Geographic)
Large spirals on Mars, as seen by an orbiting spacecraft. / Image courtesy U. Arizona/NASA
Brian Handwerk
for National Geographic News
Published April 26, 2012
Hundreds of large spirals have been discovered on Mars, and scientists think the coiled features are evidence of a type of lava flow never before seen on the red planet.
If so, the spirals would suggest that volcanoes—not ice floes, as other experts believe—shaped an unusual area near the red planet’s equator.
Athabasca Valles is a region of flow channels and valleys covered with terrain plates, structures that show clear evidence of something fracturing and drifting across the planet’s surface millions of years ago.
Scientists have been divided, however, as to whether the plates were made by the hardening of a massive lava flow or by icy “rafts”—much like Arctic pack ice—from an ancient inland sea.
Now, high-resolution pictures of Athabasca Valles from NASA’s Mars Reconnaissance Orbiter have revealed 269 coils up to a hundred feet (30 meters) wide.
“There are no known mechanisms to naturally produce spiral patterns in ice-rich environments on the scale and frequency observed in our study area,” study authors Andrew Ryan and Philip Christensen write in a new paper in this week’s issue of the journal Science.
Instead Ryan and Christensen, of Arizona State University, think the coils are most similar to features seen in smooth, slow-moving Hawaiian lava flows.
“Everything that we have observed in Athabasca Valles can be formed by lava. Although you could attribute certain features to ice, the lava coils indicate that this is not the case,” Ryan told National Geographic News in an email.
Valley Shaped by Ice or Fire?
On Earth, so-called pahoehoe lava flows can move past each other in different directions or at different speeds. The resulting shear produces a twisting motion, which coils the rubbery crust atop the flows into a distinctive shape—one that closely resembles the newfound Martian spirals.
On Earth similar spirals are found underwater on a mid-ocean ridge, where two “conveyor belts” of spreading crust move outward in opposite directions, causing the upwelling lava between them to swirl.
As with many things Martian, however, the new data remain open to interpretation.
John Murray, with the Department of Earth Sciences at the Open University in the U.K., said Ryan’s paper is interesting and that the spiral features are quite curious. But Murray still believes that the surface near Athabasca Valles shows the lingering effects of an ancient frozen sea.
“I think there are so many features here that it’s difficult to explain them other than [the theory] that this was essentially water that froze and has since sublimated away,” he said. Sublimation is when a solid turns directly into a gas.
“There is no lava that behaves in so many different ways.”
The appearance of the plates themselves, not the spirals in between, remains a main sticking point for Murray.
“You do get plates in lava, but on the scale of a few meters,” he said. “Here you’re talking about things which are kilometers long, and the only way you can do that really is to have a liquid that’s extremely mobile and fluid—water or something like water.
“If you freeze the top of that, as in the Arctic, you do get ice floes that are several kilometers or more, which is what you get on Mars in this region. You never see anything like that in a lava flow.”
A Place to Look for Life?
The debate pitting lava against ice is more than purely geological. If Athabasca Valles does show clear evidence of water ice, the region could become an important target for future Mars astrobiology missions.
“If this really is the remains of a large inland sea, that’s where you’re going to find life, if there is any there,” Murray said.
“Even if the sea was five million years old, there may still be subsurface remains of the ice, and … microfossil traces could perhaps be found there.”
Study author Ryan, meanwhile, is confident the odd features of Athabasca Valles can be explained by volcanism alone.
“I don’t believe it would be a very good place to search for life,” he said. “However, it is a very interesting place to study the volcanic and geologic history of Mars.”
(Source: National Geographic)
By Robert Kunzig
Photograph by Orsolya and Erlend Haarberg
It was five days before Christmas, and in the hut on the north flank of Eyjafjallajökull, the volcano that grounded airplanes all over Europe in 2010, Sigurður Reynir Gíslason was dishing up fish soup and pickled herring. Lunch felt like a gift. The volcano was quiet, its glacier muffled in clouds, but we’d forded icy river channels to get here, and twice Siggi’s SUV had got stuck. Outside the warm hut, gnarly birch trees formed a spiderweb of branches against the white hillside. “This is what it looked like when the Vikings arrived,” said Guðrún, Siggi’s sister. As we arrived, a ptarmigan fluttered out of the snow.
Guðrún is a geographer, Siggi a geochemist at the university in Reykjavík. They were telling me the story of Iceland’s landscape, and if you counted the smoked lamb, all four main actors were present.
Volcanoes They’ve built Iceland and kept it above the Atlantic waves for at least 16 million years, and every few years now one of them pops off. In 2010, with aviation authorities frantic about the ash billowing from Eyjafjallajökull, Siggi raced his SUV into the dark heart of the cloud. When he got out to collect some ash, expecting to hear it hailing on his helmet, the silence stunned him. “It was just like flour,” he says. But sharp as glass.
Glaciers They started coming and going around three million years ago, even before the global ice ages began. These days they’re shrinking fast but still cover the tallest volcanoes. When a fjall erupts under a jökull, it produces a jökulhlaup—a torrent of meltwater and ice that races to the sea, knocking out bridges and flooding farm fields, which soon thereafter may be buried in ash.
People The story goes that the first settlers arrived from Norway in A.D. 874—just three years after a pair of massive volcanic eruptions. Guðrún finds those ash layers in soils all the time, and nearly all human artifacts lie higher up. Before 871 Iceland, which is about the size of Kentucky, was essentially empty. The only land mammals were arctic foxes. Between eruptions it was pretty quiet, except for the wind, the sea, and the screech of seabirds.
The Icelanders infused this empty land with meaning—nearly every place seems linked to the ancient sagas somehow—but they also denuded it. Birch forests once filled lowlands and valleys, covering at least a quarter of the country; now it’s one percent. Trees were felled for charcoal until the 19th century.
Sheep Settlers brought cattle and pigs too, but then the climate turned colder for 500 years, and long-haired sheep became the mainstay. In summer hundreds of thousands still graze on open range in the highlands. Being sheep, they eat everything—including birch seedlings. Less than half of Iceland has any vegetation at all, says Guðrún. It used to be two-thirds. As fluffy volcanic soils were exposed, wind and water carried them off by the megaton.
To summarize: Humans and their beasts, struggling to survive in a land of volcanoes and glaciers, have degraded it to an astonishing degree.
If you don’t know that story, you see the astonishing beauty that remains.
On December 21, after the sun rose around 11, Siggi, Guðrún, and I tried to press east to another volcano, Katla, whose jökulhlaup in 1918 had nearly carried off their grandfather while he was bringing home the sheep. Snow on the coast road forced us back. At Eyjafjallajökull we passed a waterfall that still flowed gray with ash. The wind nearly blew the SUV off the road. Then, as we crossed the glacial river we’d forded the day before, a gap formed in the clouds over the ocean to the south. The hills north of the river were suffused with soft light.
Gunnar, the archetypal saga hero, lived in those hills, Siggi said. Minutes later we passed the mound where Gunnar, heading into exile after one killing too many, was thrown by his horse. Looking homeward, he uttered lines all Icelanders know, and Siggi rendered roughly: “Fair is the hillside, fairer than it has ever seemed. I will go home and not go abroad at all.” Iceland still exerts such pull. “Furthermore,” note Orsolya and Erlend Haarberg, who came from Norway to take these photos, “there are no trees to block the fantastic views.”
(Source: National Geographic)
By Dan Koeppel
Photograph by Tim Laman
To see a manakin in action is to encounter a spectacular song and dance act in the middle of a tropical forest. About half of the 40 known species make music by moving their body parts. And in the flush of courtship, males execute maneuvers with names like the dart, the about-face, the upright, and the backward slide (which looks exactly like a Michael Jackson moonwalk).
Charles Darwin sized up the manakin in The Descent of Man. In his 1871 account of the bird, he wrote: “The diversity of the sounds … and the diversity of the means for producing such sounds, are highly remarkable. We thus gain a high idea of their importance for sexual purposes.” But the mechanics of its music making have taken more than a century to uncover.
Just a handful of ornithologists study the club-winged manakin, which lives in Colombia and Ecuador. Probably none is more in tune with the bird than Kim Bostwick. It was Bostwick—first working with her Ph.D. adviser at Yale, Richard Prum, and then since 2002 as curator of birds and mammals at the Cornell University Museum of Vertebrates—who broke the code of the male club-winged manakin, a standout among manakins. It is the only species that uses its feathers to generate a tick, tick, ting in the hope of making a female swoon.
Scientists knew the wings were the source of the sound but didn’t know exactly how the process worked. To crack the conundrum, Bostwick recorded the bird’s movements on a video camera operating at a thousand frames per second, more than 30 times as fast as a standard camcorder. Viewing the video a few frames at a time led to a eureka moment: The bird was knocking its wings together 107 times a second. Examining the bird’s secondary feathers in the lab, Bostwick saw on each wing a specialized feather with seven separate ridges. The fifth feather rubs against the ridged feather in a plectrum-like action—in music terminology, that’s a plucking device, like a guitar pick—to reach a frequency of an astonishing 1,500 cycles per second (seven ridges, each plucked twice = 14, multiplied by 107 = 1,498). The result is a violin-like tone, somewhere between an F sharp and a G, more than two octaves above middle C. The world has nearly 10,000 species of avifauna, but no other creates sound this way—by scraping body parts together (although crickets do something similar).
Bone density appears to be critical. In a paper that will be published later this year, Bostwick and her colleagues describe how they conducted micro-CT scans of manakin wings and discovered that the wing bones are solid. Most birds have hollow bones, which lighten the load when aloft. The manakin’s bulky bones, Bostwick says, likely have evolved in order to support the knocking action of the large feathers. But how, she wants to know, does this three-and-a-half-inch bird haul around the extra weight when it flies? And how does it manage “the incredible energy cost and physics involved in using that wing”? These are the next manakin mysteries to solve.
With daylight saving time kicking off again, clock confusion is once again ticking away: Why do we spring forward? Does daylight saving time really save energy? Is it bad for your health? Get expert answers below.
When Will Daylight Savings Begin in 2012?
For most Americans, daylight saving time 2012 will begin 2 a.m. on Sunday, March 11, when most states will spring forward an hour. Time will fall back to standard time again on Sunday, November 4, 2012, when daylight saving time ends.
The federal government doesn’t require U.S. states or territories to observe daylight saving time, which is why residents of Arizona, Hawaii, Puerto Rico, the Virgin Islands, American Samoa, Guam, and the Northern Marianas Islands won’t need to change their clocks this weekend.
Where it is observed, daylight savings has been known to cause some problems.
National surveys by Rasmussen Reports, for example, show that 83 percent of respondents knew when to move their clocks ahead in spring 2010. Twenty-seven percent, though, admitted they’d been an hour early or late at least once in their lives because they hadn’t changed their clocks correctly.
It’s enough to make you wonder—why do we do use daylight saving time in the first place?
How and When Did Daylight Saving Time Start?
Ben Franklin—of “early to bed and early to rise” fame—was apparently the first person to suggest the concept of daylight savings, according to computer scientist David Prerau, author of the book Seize the Daylight: The Curious and Contentious Story of Daylight Saving Time.
While serving as U.S. ambassador to France in Paris, Franklin wrote of being awakened at 6 a.m. and realizing, to his surprise, that the sun would rise far earlier than he usually did. Imagine the resources that might be saved if he and others rose before noon and burned less midnight oil, Franklin, tongue half in cheek, wrote to a newspaper.
“Franklin seriously realized it would be beneficial to make better use of daylight but he didn’t really know how to implement it,” Prerau said.
It wasn’t until World War I that daylight savings were realized on a grand scale. Germany was the first state to adopt the time changes, to reduce artificial lighting and thereby save coal for the war effort. Friends and foes soon followed suit.
In the U.S. a federal law standardized the yearly start and end of daylight saving time in 1918—for the states that chose to observe it.
During World War II the U.S. made daylight saving time mandatory for the whole country, as a way to save wartime resources. Between February 9, 1942, and September 30, 1945, the government took it a step further. During this period daylight saving time was observed year-round, essentially making it the new standard time, if only for a few years.
Since the end of World War II, though, daylight saving time has always been optional for U.S. states. But its beginning and end have shifted—and occasionally disappeared.
During the 1973-74 Arab oil embargo, the U.S. once again extended daylight saving time through the winter, resulting in a one percent decrease in the country’s electrical load, according to federal studies cited by Prerau.
Thirty years later the Energy Policy Act of 2005 was enacted, mandating a controversial monthlong extension of daylight saving time, starting in 2007.
But does daylight saving time really save any energy?
Daylight Saving Time: Energy Saver or Just Time Suck?
In recent years several studies have suggested that daylight saving time doesn’t actually save energy—and might even result in a net loss.
Environmental economist Hendrik Wolff, of the University of Washington, co-authored a paper that studied Australian power-use data when parts of the country extended daylight saving time for the 2000 Sydney Olympics and others did not. The researchers found that the practice reduced lighting and electricity consumption in the evening but increased energy use in the now dark mornings-wiping out the evening gains.
Likewise, Matthew Kotchen, an economist at the University of California, saw in Indiana a situation ripe for study.
Prior to 2006 only 15 of the state’s 92 counties observed daylight saving time. So when the whole state adopted daylight saving time, it became possible to compare before-and-after energy use. While use of artificial lights dropped, increased air-conditioning use more than offset any energy gains, according to the daylight saving time research Kotchen led for the National Bureau of Economic Research [PDF] in 2008.
That’s because the extra hour that daylight saving time adds in the evening is a hotter hour. “So if people get home an hour earlier in a warmer house, they turn on their air conditioning,” the University of Washington’s Wolff said.
In fact, Hoosier consumers paid more on their electric bills than before they made the annual switch to daylight saving time, the study found.
But other studies do show energy gains.
In an October 2008 daylight saving time report to Congress (PDF), mandated by the same 2005 energy act that extended daylight saving time, the U.S. Department of Energy asserted that springing forward does save energy.
Extended daylight saving time saved 1.3 terawatt hours of electricity. That figure suggests that daylight saving time reduces annual U.S. electricity consumption by 0.03 percent and overall energy consumption by 0.02 percent.
While those percentages seem small, they could represent significant savings because of the nation’s enormous total energy use.
What’s more, savings in some regions are apparently greater than in others.
California, for instance, appears to benefit most from daylight saving time—perhaps because its relatively mild weather encourages people to stay outdoors later. The Energy Department report found that daylight saving time resulted in an energy savings of one percent daily in the state.
But Wolff, one of many scholars who contributed to the federal report, suggested that the numbers were subject to statistical variability and shouldn’t be taken as hard facts.
And daylight savings’ energy gains in the U.S. largely depend on your location in relation to the Mason-Dixon Line, Wolff said.
“The North might be a slight winner, because the North doesn’t have as much air conditioning,” he said. “But the South is a definite loser in terms of energy consumption. The South has more energy consumption under daylight saving.”
Daylight Saving Time: Healthy or Harmful?
For decades advocates of daylight savings have argued that, energy savings or no, daylight saving time boosts health by encouraging active lifestyles—a claim Wolff and colleagues are currently putting to the test.
“In a nationwide American time-use study, we’re clearly seeing that, at the time of daylight saving time extension in the spring, television watching is substantially reduced and outdoor behaviors like jogging, walking, or going to the park are substantially increased,” Wolff said. “That’s remarkable, because of course the total amount of daylight in a given day is the same.”
But others warn of ill effects.
Till Roenneberg, a chronobiologist at Ludwig-Maximilians University in Munich, Germany, said his studies show that our circadian body clocks-set by light and darkness-never adjust to gaining an “extra” hour of sunlight to the end of the day during daylight saving time.
“The consequence of that is that the majority of the population has drastically decreased productivity, decreased quality of life, increasing susceptibility to illness, and is just plain tired,” Roenneberg said.
One reason so many people in the developed world are chronically overtired, he said, is that they suffer from “social jet lag.” In other words, their optimal circadian sleep periods are out of whack with their actual sleep schedules.
Shifting daylight from morning to evening only increases this lag, he said.
“Light doesn’t do the same things to the body in the morning and the evening. More light in the morning would advance the body clock, and that would be good. But more light in the evening would even further delay the body clock.”
Other research hints at even more serious health risks.
A 2008 study in the New England Journal of Medicine concluded that, at least in Sweden, heart attack risks go up in the days just after the spring time change. “The most likely explanation to our findings are disturbed sleep and disruption of biological rhythms,” lead author Imre Janszky, of the Karolinska Institute’s Department of Public Health Sciences in Stockholm, told National Geographic News via email.
Daylight Savings Lovers, Haters
With verdicts on the benefits, or costs, of daylight savings so split, it may be no surprise that the yearly time changes inspire polarized reactions.
In the U.K., for instance, the Lighter Later movement-part of 10:10, a group advocating cutting carbon emissions-argues for a sort of extreme daylight savings. First, they say, move standard time forward an hour, then keep observing daylight saving time as usual-adding two hours of evening daylight to what we currently consider standard time.
The folks behind Standardtime.com, on the other hand, want to abolish daylight saving time altogether. Calling energy-efficiency claims “unproven,” they write: “If we are saving energy let’s go year round with Daylight Saving Time. If we are not saving energy let’s drop Daylight Saving Time!”
But don’t most people enjoy that extra evening sun every summer? Even that remains in doubt.
National telephone surveys by Rasmussen Reports from spring 2010 and fall 2009 deliver the same answer. Most people just “don’t think the time change is worth the hassle.” Forty-seven percent agreed with that statement, while only 40 percent disagreed.
But Seize the Daylight author David Prerau said his research on daylight saving time suggests most people are fond of it.
“I think the first day of daylight saving time is really like the first day of spring for a lot of people,” Prerau said. “It’s the first time that they have some time after work to make use of the springtime weather.
“I think if you ask most people if they enjoy having an extra hour of daylight in the evening eight months a year, the response would be pretty positive.”
(Source: National Geographic)
By Peter Gwin
Photograph by Brent Stirton
The rifle shot boomed through the darkening forest just as Damien Mander arrived at his campfire after a long day training game ranger recruits in western Zimbabwe’s Nakavango game reserve. His thoughts flew to Basta, a pregnant black rhinoceros, and her two-year-old calf. That afternoon one of his rangers had discovered human footprints following the pair’s tracks as Basta sought cover in deep bush to deliver the newest member of her threatened species.
Damien, a hard-muscled former Australian Special Forces sniper with an imposing menagerie of tattoos, including “Seek & Destroy” in gothic lettering across his chest, swiveled his head, trying to place the direction of the shot. “There, near the eastern boundary,” he pointed into the blackness. “Sounded like a .223,” he said, identifying the position and caliber, a habit left over from 12 tours in Iraq. He and his rangers grabbed shotguns, radios, and medical kits and piled into two Land Cruisers. They roared into the night, hoping to cut off the shooter. The rangers rolled down their windows and listened for a second shot, which would likely signal Basta’s calf was taken as well.
It was an ideal poacher’s setup: half-moon, almost no wind. The human tracks were especially ominous. Poaching crews often pay trackers to find the rhinos, follow them until dusk, then radio their position to a shooter with a high-powered rifle. After the animal is down, the two horns on its snout are hacked off in minutes, and the massive carcass is left to hyenas and vultures. Nearly always the horns are fenced to an Asian buyer; an enterprising crew might also cut out Basta’s fetus and the eyes of the mother and calf to sell to black magic or muti practitioners. If this gang was well organized, a group of heavily armed men would be covering the escape route, ready to ambush the rangers.
As the Land Cruiser bucked over rutted tracks, Damien did a quick calculation—between his vehicles he had two antiquated shotguns with about a dozen shells. Based on the sound of the shot, the poachers held an advantage in firepower. If the rangers did pick up a trail and followed on foot, they would have to contend with lions, leopards, and hyenas out hunting in the dark.
In the backseat of one of the speeding Land Cruisers, Benzene, a Zimbabwean ranger who had spent nearly a year watching over Basta and her calf and knew the pair intimately, loaded three shells into his shotgun, flicked on the safety, and chambered a round. As we bounced into the night, he said, “It is better for the poachers if they meet a lion than if they meet us.”
AND SO GOES A NIGHT on the front lines of southern Africa’s ruthless and murky rhino war, which since 2006 has seen more than a thousand rhinos slaughtered, some 22 poachers gunned down and more than 200 arrested last year in South Africa alone. At the bloody heart of this conflict is the rhino’s horn, a prized ingredient in traditional Asian medicines. Though black market prices vary widely, as of last fall dealers in Vietnam quoted prices ranging from $33 to $133 a gram, which at the top end is double the price of gold and can exceed the price of cocaine.
Although the range of the two African species—the white rhino and its smaller cousin, the black rhino—has been reduced primarily to southern Africa and Kenya, their populations had shown encouraging improvement. In 2007 white rhinos numbered 17,470, while blacks had nearly doubled to 4,230 since the mid ’90s.
For conservationists these numbers represented a triumph. In the 1970s and ’80s, poaching had devastated the two species. Then China banned rhino horn from traditional medicine, and Yemen forbade its use for ceremonial dagger handles. All signs seemed to point to better days. But in 2008 the number of poached rhinos in South Africa shot up to 83, from just 13 in 2007. By 2010 the figure had soared to 333, followed by over 400 last year. Traffic, a wildlife trade monitoring network, found most of the horn trade now leads to Vietnam, a shift that coincided with a swell of rumors that a high-ranking Vietnamese official used rhino horn to cure his cancer.
Meanwhile in South Africa, attracted by spiraling prices—and profits—crime syndicates began adding rhino poaching to their portfolios.
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