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Categories: Paleontology: Climate, Paleontology: Fossils
Published Researchers studying ocean transform faults, describe a previously unknown part of the geological carbon cycle
(via sciencedaily.com) Original source 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.
Published The hidden rule for flight feathers -- and how it could reveal which dinosaurs could fly
(via sciencedaily.com) Original source 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.
Published Surprisingly vibrant color of 12-million-year-old snail shells
(via sciencedaily.com) Original source 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.
Published New fossil site of worldwide importance uncovered in southern France
(via sciencedaily.com) Original source 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.
Published Ancient pollen trapped in Greenland ice uncovers changes in Canadian forests over 800 years
(via sciencedaily.com) Original source 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.
Published Ice cores provide first documentation of rapid Antarctic ice loss in the past
(via sciencedaily.com) Original source 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.
Published What turned Earth into a giant snowball 700 million years ago? Scientists now have an answer
(via sciencedaily.com) Original source 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.
Published Ancient Australian air-breathing fish from 380 million years ago
(via sciencedaily.com) Original source 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.
Published Rare 3D fossils show that some early trees had forms unlike any you've ever seen
(via sciencedaily.com) Original source 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.
Published Permafrost alone holds back Arctic rivers -- and a lot of carbon
(via sciencedaily.com) Original source 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.
Published Did dementia exist in ancient Greek and Rome?
(via sciencedaily.com) Original source Did the ancient Greeks and Romans experience Alzheimer's? Medical texts from 2,500 years ago rarely mention severe memory loss, suggesting today's widespread dementia stems from modern environments and lifestyles, a new analysis shows.
Published Scientists pinpoint growth of brain's cerebellum as key to evolution of bird flight
(via sciencedaily.com) Original source 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?
Published How did humans learn to walk? New evolutionary study offers an earful
(via sciencedaily.com) Original source 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.
Published DNA from preserved feces reveals ancient Japanese gut environment
(via sciencedaily.com) Original source DNA from ancient feces can offer archaeologists new clues about the life and health of Japanese people who lived thousands of years ago, according to a new study.
Published Ancient brown bear genomes sheds light on Ice Age losses and survival
(via sciencedaily.com) Original source 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?
Published New tool predicts flood risk from hurricanes in a warming climate
(via sciencedaily.com) Original source 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.
Published New pieces in the puzzle of first life on Earth
(via sciencedaily.com) Original source Microorganisms were the first forms of life on our planet. The clues are written in 3.5 billion-year-old rocks by geochemical and morphological traces, such as chemical compounds or structures that these organisms left behind. However, it is still not clear when and where life originated on Earth and when a diversity of species developed in these early microbial communities. Evidence is scarce and often disputed. Now, researchers have uncovered key findings about the earliest forms of life. In rock samples from South Africa, they found evidence dating to around 3.42 billion years ago of an unprecedentedly diverse carbon cycle involving various microorganisms. This research shows that complex microbial communities already existed in the ecosystems during the Palaeoarchaean period.
Published Complex green organisms emerged a billion years ago
(via sciencedaily.com) Original source Of all the organisms that photosynthesize, land plants have the most complex form. How did this morphology emerge? A team of scientists has taken a deep dive into the evolutionary history of morphological complexity in streptophytes, which include land plants and many green algae. Their research allowed them to go back in time to investigate lineages that emerged long before land plants existed.
Published Student discovers 200-million-year-old flying reptile
(via sciencedaily.com) Original source Gliding winged-reptiles were amongst the ancient crocodile residents of the Mendip Hills in Somerset, England, researchers at the have revealed.
Published Ice age could help predict oceans' response to global warming
(via sciencedaily.com) Original source 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.