The crystal structure of MgCO3-II has long been discussed in the literature where DFT-based model calculations predict a pressure-induced transition of the carbon atom from the sp2 to the sp3 type of bonding. We have now determined the crystal structure of iron-bearing MgCO3-II based on single-crystal X-ray diffraction measurements using synchrotron radiation. We laser-heated a synthetic (Mg0.85Fe0.15)CO3 single crystal at 2500 K and 98 GPa and observed the formation of a monoclinic phase with composition (Mg2.53Fe0.47)C3O9 in the space group C2/m that contains tetra­hedrally coordinated carbon, where CO44− tetra­hedra are linked by corner-sharing oxygen atoms to form three-membered C3O96− ring anions. The crystal structure of (Mg0.85Fe0.15)CO3 (magnesium iron carbonate) at 98 GPa and 300 K is reported here as well. In comparison with previous structure-prediction calculations and powder X-ray diffraction data, our structural data provide reliable information from experiments regarding atomic positions, bond lengths, and bond angles.

Two Andean bear cubs born at the National Zoo in the early morning of Dec. 13 to 6-year-old Billie Jean.

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All bear species except for one live in either temperate or tropical woodlands. Only the polar bear is a stranger to the forest, living and […]

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Giant pandas. Grizzlies. Polar bears. You’ve probably heard a lot about these bear species, but what about Andean bears? To the Quechua and Aymara, the […]

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For the first time, a team from the Smithsonian Conservation Biology Institute’s (SCBI) Center for Conservation Education and Sustainability collected photo evidence of an Andean […]

The post Scientists Find Andean Bears with Camera Traps In Peru appeared first on Smithsonian Insider.

The world’s most indestructible species, the tardigrade, an eight-legged micro-animal, also known as the water bear, will survive until the Sun dies, according to a […]

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Keeper Tracey Barnes talks about Billie Jean, an Andean bear, and her two new cubs at the Smithsonian's National Zoo.

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What is the average blood pressure of a geriatric sloth bear? Asia Trail keeper Stacey Tabellario is hoping to learn exactly that, as she trains […]

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Hunting has obvious impacts on wild populations. However, new research concludes that for Scandinavian brown bears (Ursus arctos), it also contributes to the killing of cubs by adult males to increase the male's chances of mating with the cubs' mother. The researchers say that this indirect effect of hunting should be considered when developing sustainable hunting quotas and management plans.

The impacts of climate changes can force animal- and, over a longer time period, plant species to shift their range. Forests in temperate regions, such as north-western Spain, will be increasingly exposed to drought over the next few decades, which is likely to cause geographical changes in their distribution and make-up1. New patterns of plant occupancy or plant extinction have a bottom-up effect on animal species dependent on them, which can significantly impact on isolated or endangered populations of animals. This study sought to assess the potential impact of climate change on the brown-bear (Ursus arctos) population in the Cantabrian Mountains.

The popularity of weird beards and mustaches among young men living in Brooklyn, N.Y., may be more than just a hipster fad.

Increased sea ice drift forces polar bears to expend more energy walking on a fast-moving 'treadmill' of sea ice.

Mongolia, the host of this year's World Environment Day, is home to Earth's rarest bear. Conservationists hope 2013 will mark the start of its comeback.

Wildlife photographer Michel Rawicki captures polar bears in their private moments.

As polar bears struggle to survive in the fast-changing Arctic, MNN presents a tribute to the animals' legendary power, precocity and perseverance.

A BBC videographer learns what an Arctic seal's final moments might look like.

The people of Churchill, Manitoba, live among polar bears — some of the world's most dangerous predators — for several months each year.

The U.S.-backed proposal was opposed by Canada, which is home to two-thirds of the world's polar bears.

Polar bears and brown bears diverged much longer ago than previously thought.

The governor’s office of the Arctic Svalbard islands is seeking to fill the temporary position beginning July 8.

The orphaned polar bear cub that was rescued in Alaska earlier this year arrived safely at a new home in Buffalo, N.Y.

The zoo s hoping the 2-year-old male will pair up with the resident female and produce a cub.

The Central Park Zoo’s celebrated star was made famous when an animal psychologist was called in to address the bear’s problems.

In the next decade, the tropics will suffer unprecedented climate change effects, long before the Arctic and its polar bears see big shifts.

Explore.org has affixed several high-definition cameras to locations in Churchill, Manitoba, the 'Polar Bear Capital of the World.'

Polar-bear dens, where mama bears raise young cubs during the harsh Alaska winters, could be identified using laser technology.

The culprit of the sudden death of famed polar bear tot Knut has been found, says an international team of scientists.

The 2-month-old cub at the Toronto Zoo hasn't quite nailed walking, but he's definitely got being cute figured out.

Polar bears have shifted to a diet of more land-based food in response to climate change and melting sea ice.

The conservation nonprofit Polar Bears International will use the 360-degree panoramas for educational outreach and scientific research.

The cuddly duo — a boy and a girl born at the Hellabrunn Zoo on Dec. 9 — explore their enclosure with their mom, Giovanna.

Far from the frosty climate of the Arctic Circle, this adorable family is making do in the summer heat with a brand new swimming pool.

The world's southernmost population of polar bears is waiting for sea ice to form just weeks before the U.N.'s climate change conference.

The new season of Smithsonian Channel's 'Polar Bear Town' will explore the intersection of humans and the 'Lords of the Arctic' in Manitoba.

Expect one if you buy the new all-electric Nissan Leaf.

Automaker pulls back the curtain to reveal the magic behind its latest ad for the all-electric Leaf.

Triassic fossils found on lands that were previously part of Bears Ears National Monument could fall under 'multiple-use' management.

The extinct cave bear Ursus spelaeus appears to have descended from a vegetarian line of bears.

Study reveals that open-water swims have a dramatic effect on young cubs, which are forced to follow their mothers in search of food and solid ground.

The new white Coca-Cola cans are part of a fundraising campaign to protect the Arctic.

Polar bears have ruled the Arctic for 100,000 years, but now they're struggling to keep up as the region undergoes a dramatic transformation.

Scientists have released the first 'point of view' video filmed by a wild polar bear, offering a glimpse into the animals' daily lives.

You can watch the live stream of the conference and follow my live tweets from the event.

Whether they were based on the real thing or imagined, we welcomed these bears into our homes with abandon.

This grizzly bear cub thought he was just enjoying a day at the river's edge before a scallop shell ruined it.

Competitors from around the world line up on an Arctic ice floe to tackle one of the world's most difficult 26.2-mile races.

When the Winter Olympics wrap up, Vancouver will be passing more than one torch. The city could light the way for green cities of the future by proving economic

When you can smell garbage from miles away, pizza doesn't stand a chance with bears.

The predators burn energy 1.6 times faster than previously thought, a study finds, helping explain why the loss of sea ice hits them so hard.

Brown bears visit Brooks River every summer to enjoy some delicious salmon, and humans can come along for the ride via webcams.