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Categories: Paleontology: Climate, Paleontology: Early Mammals and Birds

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Among the vast expanse of Antarctica lies the Thwaites Glacier, the world's widest glacier measuring about 80 miles on the western edge of the continent. Despite its size, the massive landform is losing about 50 billion tons of ice more than it is receiving in snowfall, which places it in a precarious position in respect to its stability. Accelerating ice loss has been observed since the 1970s, but it is unclear when this significant melting initiated -- until now. A new study suggests that the significant glacial retreat of two glaciers on the west coast of Antarctica began in the 1940's, likely spurred by climate change.

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The evolutionary success of the first large predators on land was driven by their need to improve as killers, researchers suggest.

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A detailed survey of the volcanic underwater deposits around the Kikai caldera in Japan clarified the deposition mechanisms as well as the event's magnitude. As a result, the research team found that the event 7,300 years ago was the largest volcanic eruption in the Holocene by far.

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It has been long assumed that Utah's Bonneville Salt Flats was formed as its ancient namesake lake dried up 13,000 years ago. But new research has gutted that narrative, determining these crusts did not form until several thousand years after Lake Bonneville disappeared, which could have important implications for managing this feature that has been shrinking for decades to the dismay of the racing community and others who revere the saline pan 100 miles west of Salt Lake City. Relying on radiocarbon analysis of pollen found in salt cores, the study concludes the salt began accumulating between 5,400 and 3,500 years ago, demonstrating how this geological feature is not a permanent fixture on the landscape.

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In a new study, paleontologists describe the oldest-known leaf-nosed bat fossils, which were found along the banks of the Panama Canal. They're also the oldest bat fossils from Central America, preserved 20-million years ago when Panama and the rest of North America were separated from southern landmass by a seaway at least 120 miles wide.

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The bead found at the La Prele Mammoth site in Wyoming's Converse County is about 12,940 years old and made of bone from a hare.

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This study reports widespread mineral carbonation of mantle rocks in an oceanic transform fueled by magmatic degassing of CO2. The findings describe a previously unknown part of the geological carbon cycle in transform faults that represent one of the three principal plate boundaries on Earth. The confluence of tectonically exhumed mantle rocks and CO2-rich alkaline basalt formed through limited extents of melting characteristic of the St. Paul's transform faults may be a pervasive feature at oceanic transform faults in general. Because transform faults have not been accounted for in previous estimates of global geological CO2 fluxes, the mass transfer of magmatic CO2 to the altered oceanic mantle and seawater may be larger than previously thought.

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Scientists examined hundreds of birds in museum collections and discovered a suite of feather characteristics that all flying birds have in common. These 'rules' provide clues as to how the dinosaur ancestors of modern birds first evolved the ability to fly, and which dinosaurs were capable of flight.

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The Greenland ice sheet lies thousands of miles from North America yet holds clues to the distant continent's environmental history. Nearly two miles thick in places, the ice sheet grows as snow drifts from the sky and builds up over time. But snow isn't the only thing carried in by air currents that swirl around the atmosphere, with microscopic pollen grains and pieces of ash mixing with snowfall and preserving records of the past in the ice. A new study examined these pollen grains and identified how eastern Canada's forests grew, retreated, and changed through time.

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Researchers have uncovered the first direct evidence that the West Antarctic Ice Sheet shrunk suddenly and dramatically at the end of the Last Ice Age, around eight thousand years ago. The evidence, contained within an ice core, shows that in one location the ice sheet thinned by 450 meters -- that's more than the height of the Empire State Building -- in just under 200 years.

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Inspired during field work in South Australia's Flinders Ranges, geoscientists have proposed that all-time low volcanic carbon dioxide emissions triggered a 57-million-year-long global 'Sturtian' ice age.

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A new study provides the first evidence that the Arctic's frozen soil is the dominant force shaping Earth's northernmost rivers, confining them to smaller areas and shallower valleys than rivers to the south. But as climate change weakens Arctic permafrost, the researchers calculate that every 1 degree Celsius of global warming could release as much carbon as 35 million cars emit in a year as polar waterways expand and churn up the thawing soil.

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Evolutionary biologists report they have combined PET scans of modern pigeons along with studies of dinosaur fossils to help answer an enduring question in biology: How did the brains of birds evolve to enable them to fly?

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A new study, which centers on evidence from skulls of a 6-million-year-old fossil ape, Lufengpithecus, offers important clues about the origins of bipedal locomotion courtesy of a novel method: analyzing its bony inner ear region using three-dimensional CT-scanning. The inner ear appears to provide a unique record of the evolutionary history of ape locomotion.

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The brown bear is one of the largest living terrestrial carnivores, and is widely distributed across the Northern Hemisphere. Unlike many other large carnivores that went extinct at the end of the last Ice Age (cave bear, sabretoothed cats, cave hyena), the brown bear is one of the lucky survivors that made it through to the present. The question has puzzled biologists for close to a century -- how was this so?

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A new method predicts how much flooding a coastal community is likely to experience as hurricanes evolve due to climate change. Using New York as a test case, the model predicts Hurricane Sandy-level flooding will occur roughly every 30 years by 2099.

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A new way to measure the ocean oxygen level and its connections with carbon dioxide in the Earth's atmosphere during the last ice age could help explain the role oceans played in past glacial melting cycles and improve predictions of how ocean carbon cycles will respond to global warming.

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The new theoretical research proposes that animal size over time depends on two key ecological factors.

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Southern Africa contains the vast majority of the world's remaining populations of both black and white rhinoceroses (80% and 92%, respectively). The region's climate is changing rapidly as a result global warming. Traditional conservation efforts aimed at protecting rhinos have focused on poaching, but until now, there has been no analysis of the impact that climate change may have on the animals. A research team has recently reported that, though the area will be affected by both higher temperatures and changing precipitation, the rhinos are more sensitive to rising temperatures, which will quickly increase above the animals' acceptable maximum threshold.

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When combined with data from tree-ring records, stalagmites can open up a unique archive to study natural climate fluctuations, a research team has demonstrated. The researchers analyzed the isotopic composition of oxygen in a stalagmite formed from calcareous water in a cave in southern Germany. In conjunction with the data acquired from tree rings, they were able to reconstruct short-term climate fluctuations over centuries and correlate them with historically documented environmental events.