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Categories: Paleontology: Climate, Paleontology: General

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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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Until recently, Orthacanthus gracilis could have been considered the 'John Smith' of prehistoric shark names, given how common it was. Three different species of sharks from the late Paleozoic Era -- about 310 million years ago -- were mistakenly given that same name, causing lots of grief to paleontologists who studied and wrote about the sharks through the years and had trouble keeping them apart. But now a professor has finished the arduous task of renaming two of the three sharks -- and in the process rediscovered a wealth of fossil fishes that had been stored at a museum for years but had been largely forgotten.

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Palaeontological analysis shows that a renowned fossil thought to show soft tissue preservation is in fact just paint. The fossil discovered in 1931 was thought to be an important specimen for understanding early reptile evolution. While not all of the celebrated fossil is a forgery, scientists urge caution in how the fossil is utilized in future.

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New research has shown that the tropical subsurface ocean gained oxygen during the Paleocene-Eocene Thermal Maximum (commonly referred to as PETM). During this short-lived interval of time in Earth s history that occurred 56 million years ago the average temperatures rose by up to six degrees within a few thousand years.

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A new study explores the weight great fossil sites have on our understanding of evolutionary relationships between fossil groups and quantified the power these sites have on our understanding of evolutionary history. Surprisingly, the authors discovered that the wind-swept sand deposits of the Late Cretaceous Gobi Desert's extraordinarily diverse and well-preserved fossil lizard record shapes our understanding of their evolutionary history more than any other site on the planet.

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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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Snail shells are often colorful and strikingly patterned. This is due to pigments that are produced in special cells of the snail and stored in the shell in varying concentrations. Fossil shells, on the other hand, are usually pale and inconspicuous because the pigments are very sensitive and have already decomposed. Residues of ancient color patterns are therefore very rare. This makes a new discovery all the more astonishing: researchers found pigments in twelve-million-year-old fossilized snail shells.

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Nearly 400 exceptionally well-preserved fossils dating back 470 million years have been discovered in the south of France by two amateur paleontologists. The discovery provides unprecedented information on the polar ecosystems of the Ordovician period.

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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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Dinosaurs' range of locomotion made them incredibly adaptable, researchers have found.

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The rivers of Australia, which once flowed across its now dry interior, used to host a range of bizarre animals -- including a sleek predatory lobe-finned fish with large fangs and bony scales. The newly described fossil fish discovered in remote fossil fields west of Alice Springs has been named Harajicadectes zhumini by palaeontologists.

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In the fossil record, trees typically are preserved with only their trunks. They don't usually include any leaves to show what their canopies and overall forms may have looked like. In a new study, researchers describe fossilized trees from New Brunswick, Canada with a surprising and unique three-dimensional crown shape.

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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?