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New research predicts the future of coral reefs under climate change

New research predicts the future of coral reefs under climate change | Paleomatica | Scoop.it

New climate model projections of the world's coral reefs reveal which reefs will be hit first by annual coral bleaching, an event that poses the gravest threat to one of the Earth's most important ecosystems.

 

These high-resolution projections, based on global climate models, predict when and where annual coral bleaching will occur. The projections show that reefs in Taiwan and around the Turks and Caicos archipelago will be among the world's first to experience annual bleaching. Other reefs, like those off the coast of Bahrain, in Chile and in French Polynesia, will be hit decades later, according to research recently published in the journal Scientific Reports.


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Fossilworks: Gateway to the Paleobiology Database

Fossilworks: Gateway to the Paleobiology Database | Paleomatica | Scoop.it
Fossilworks hosts query, analysis, and download functions used to access large paleontological data sets. It presents taxonomic, distributional, and ecological data about the entire fossil record.
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Museums and the Web: 20 Years of Debate on Digital Transformation | Article | CCCB LAB

Museums and the Web: 20 Years of Debate on Digital Transformation | Article | CCCB LAB | Paleomatica | Scoop.it
Museums and the Web 2016. Digital transformation and organizational change, towards Open Source creation and accessible contents.

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New Scans Made a Surprising Discovery in King Tut’s Tomb | #History #Egyptology

New Scans Made a Surprising Discovery in King Tut’s Tomb | #History #Egyptology | Paleomatica | Scoop.it
Late last year, radar scans at King Tut’s tomb revealed the possible presence of a secret chamber. A more detailed analysis of this data shows not just the presence of a hidden room—but also unidentified objects that are comprised of metal and organic materials.

 

Learn more:

 

http://www.scoop.it/t/21st-century-innovative-technologies-and-developments/?tag=Egyptology

 


Via Gust MEES
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Late last year, radar scans at King Tut’s tomb revealed the possible presence of a secret chamber. A more detailed analysis of this data shows not just the presence of a hidden room—but also unidentified objects that are comprised of metal and organic materials.

 

Learn more:

 

http://www.scoop.it/t/21st-century-innovative-technologies-and-developments/?tag=Egyptology

 

 

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Gust MEES's curator insight, March 17, 2016 10:11 AM
Late last year, radar scans at King Tut’s tomb revealed the possible presence of a secret chamber. A more detailed analysis of this data shows not just the presence of a hidden room—but also unidentified objects that are comprised of metal and organic materials.

 

 

 

Learn more / En savoir plus / Mehr erfahren:

 

http://www.scoop.it/t/21st-century-innovative-technologies-and-developments/?tag=Egyptology

 

Roy Tng's curator insight, March 20, 2016 8:20 AM

Late last year, radar scans at King Tut’s tomb revealed the possible presence of a secret chamber. A more detailed analysis of this data shows not just the presence of a hidden room—but also unidentified objects that are comprised of metal and organic materials.

 

 

 

Learn more / En savoir plus / Mehr erfahren:

 

http://www.scoop.it/t/21st-century-innovative-technologies-and-developments/?tag=Egyptology

 

Roy Tng's curator insight, March 20, 2016 8:22 AM
Late last year, radar scans at King Tut’s tomb revealed the possible presence of a secret chamber. A more detailed analysis of this data shows not just the presence of a hidden room—but also unidentified objects that are comprised of metal and organic materials.

 

 

 

Learn more / En savoir plus / Mehr erfahren:

 

http://www.scoop.it/t/21st-century-innovative-technologies-and-developments/?tag=Egyptology

 

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Hobbits Were a Separate Species, Ancient Chompers Show

Hobbits Were a Separate Species, Ancient Chompers Show | Paleomatica | Scoop.it

An ancient, 3-foot-tall (0.9 meters) human whose diminutive stature has earned it the nickname "hobbit" has puzzled evolutionary scientists since its little bones were discovered on the Indonesian island of Flores. Some have suggested the individual was a Homo sapiens with some miniaturizing disorder.

 

Now, teeth from the hobbit suggest it belonged to a unique species rather than a modern human with a growth disorder. The new research also suggests hobbits may share a direct ancestor with modern humans.


Via Kathy Bosiak, Dr. Stefan Gruenwald
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After The Nepal Earthquake, Everest Is A Little Shorter

After The Nepal Earthquake, Everest Is A Little Shorter | Paleomatica | Scoop.it

The world’s tallest mountain is a little shorter after the newly-named Gorka earthquake that hit Nepal in late April, 2015.

 

The Nepal earthquake that hit just before noon on Saturday, April 26, 2015 officially has a name: it’s the Gorkha earthquake. The sudden slip of the tectonic plates during the earthquake literally reshaped the land. In a continent-continent collision like this one, the area closest to the fault rupture is uplifted, while the previously-buckled plate interior slaps flat, subsiding in the release of stress. The European Space Agency’s Sentinel-1A satellite tracked both uplift [blue] and subsidence [yellow], recording elevation changes of up to 1 meter, and a horizontal north-south shift of up to 2 meters.

 

They’ve used the same data to createinterferograms of how the region has changed in consecutive measurements before and after the earthquake. Each coloured fringe represents about 10 centimeters of displacement. Overall, Kathmandu is little taller and Mount Everest is a tiny bit shorterthan it was a month ago. Poor weather not only made things a little bit more miserable on the ground, but also limited the utility of fly-overs from NASA’s satellite network.

 

In related news, as part of efforts to increase access to hazard mitigation and risk reduction research, the Seismological Society of America has temporarily opened access to their collection of articles on tectonics, structure, and earthquake history of the Himalayas.

 

Check out more ways satellite imagery has been used in the response to the Gorkha earthquake on the American Geophysical Union’s Trembling Earth.


Via Dr. Stefan Gruenwald
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Lorraine Chaffer's curator insight, June 1, 2015 1:51 AM

Australian Curriculum

The causes, impacts and responses to a geomorphological hazard (ACHGK053)


GeoWorld 8

Chapter 4: Hazards: causes, impacts and responses

(4.5 - 4.6 Earthquakes)

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Intact Proteins Found in Fossils That Are Supposedly 8-18 Million Years Old

Intact Proteins Found in Fossils That Are Supposedly 8-18 Million Years Old | Paleomatica | Scoop.it
Recently, I ran across a very interesting study that adds to the list of surprises for those who think that some fossils are millions of years old. The authors were analyzing the fossilized shells of an extinct group of marine mollusks from the genus Ecphora. Unlike many mollusk groups, the fossilized shells of the Ecphora are colored reddish-brown. The authors decided to find out what produces this colorization, so they soaked the fossils in weak acid to remove the minerals. What remained were thin sheets of organic residue that had all the characteristics one would expect if they were made of proteins.

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Free Access to Science Research Doesn't Benefit Everyone

Free Access to Science Research Doesn't Benefit Everyone | Paleomatica | Scoop.it

Open is better than closed. That rule applies for a lot of things: presents, beer, restaurants. And, many argue, science.

The open-science movement has a lot of interlocking parts. Open-access publishing advocates want papers to be available to anybody, open-data supporters want data to be downloadable, and those arguing for open source want the software scientists use to be shared with everyone. The idea is simple: The more people who have access to papers, data, and software, the better it is for the world.

And the drumbeat of openness is getting louder. Last month, CERN opened up its vast datasets to the public and the Bill & Melinda Gates Foundation announced that any research it funded would have to be published only in journals that offer open access. “We believe that published research resulting from our funding should be promptly and broadly disseminated,” they wrote in their policy statement.

There is a lot of promise in open access. But there are a lot of problems too.


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Oceans arrived early on Earth: Primitive meteorites were the likely source of water

Oceans arrived early on Earth: Primitive meteorites were the likely source of water | Paleomatica | Scoop.it

Earth is known as the Blue Planet because of its oceans, which cover more than 70 percent of the planet's surface and are home to the world's greatest diversity of life. While water is essential for life on the planet, the answers to two key questions have eluded us: Where did Earth's water come from and when? While some hypothesize that water came late to Earth, well after the planet had formed, findings from a new study significantly move back the clock for the first evidence of water on Earth and in the inner solar system.

 

"The answer to one of the basic questions is that our oceans were always here. We didn't get them from a late process, as was previously thought," said Adam Sarafian, the lead author of the paper published Oct. 31, 2014, in the journal Science and a MIT/WHOI Joint Program student in the Geology and Geophysics Department.

 

One school of thought was that planets originally formed dry, due to the high-energy, high-impact process of planet formation, and that the water came later from sources such as comets or "wet" asteroids, which are largely composed of ices and gases.

 

"With giant asteroids and meteors colliding, there's a lot of destruction," said Horst Marschall, a geologist at WHOI and coauthor of the paper. "Some people have argued that any water molecules that were present as the planets were forming would have evaporated or been blown off into space, and that surface water as it exists on our planet today, must have come much, much later -- hundreds of millions of years later."

 

The study's authors turned to another potential source of Earth's water -- carbonaceous chondrites. The most primitive known meteorites, carbonaceous chondrites, were formed in the same swirl of dust, grit, ice and gasses that gave rise to the sun some 4.6 billion years ago, well before the planets were formed. "These primitive meteorites resemble the bulk solar system composition," said WHOI geologist and coauthor Sune Nielsen. "They have quite a lot of water in them, and have been thought of before as candidates for the origin of Earth's water."

 

In order to determine the source of water in planetary bodies, scientists measure the ratio between the two stable isotopes of hydrogen: deuterium and hydrogen. Different regions of the solar system are characterized by highly variable ratios of these isotopes. The study's authors knew the ratio for carbonaceous chondrites and reasoned that if they could compare that to an object that was known to crystallize while Earth was actively accreting then they could gauge when water appeared on Earth.

 

To test this hypothesis, the research team, which also includes Francis McCubbin from the Institute of Meteoritics at the University of New Mexico and Brian Monteleone of WHOI, utilized meteorite samples provided by NASA from the asteroid 4-Vesta. The asteroid 4-Vesta, which formed in the same region of the solar system as Earth, has a surface of basaltic rock -- frozen lava. These basaltic meteorites from 4-Vesta are known as eucrites and carry a unique signature of one of the oldest hydrogen reservoirs in the solar system. Their age -- approximately 14 million years after the solar system formed -- makes them ideal for determining the source of water in the inner solar system at a time when Earth was in its main building phase. The researchers analyzed five different samples at the Northeast National Ion Microprobe Facility -- a state-of-the-art national facility housed at WHOI that utilizes secondary ion mass spectrometers. This is the first time hydrogen isotopes have been measured in eucrite meteorites.


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The Earth's Ozone Layer is Making an Impressive Recovery | Big Think

The Earth's Ozone Layer is Making an Impressive Recovery | Big Think | Paleomatica | Scoop.it
Scientists have confirmed a sizable improvement in ozone levels over the past decade. The news is a testament to the world's noble dedication to reducing usage of hazardous chemicals.

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Paleontologists just found the dinosaur Dreadnoughtus, an 85-foot-long titan - the most massive ever discovered

Paleontologists just found the dinosaur Dreadnoughtus, an 85-foot-long titan - the most massive ever discovered | Paleomatica | Scoop.it

Today an international team of paleontologists unveiled the newest Mesozoic giant: Dreadnoughtus schrani. Weighing in at an astonishing 65 tons, standing two stories high at the shoulder, and measuring 85 feet long, this titan is the heaviest dinosaur we've ever (accurately) measured. And its discovery represents the most fossil mass ever found for a single organism—a paleontologist's dream. 

"For the largest dinosaurs, which we call titanosaurs, finding anything around 20 percent of the fossil is usually considered a home run," says Kenneth Lacovara, the lead Drexel University paleontologist behind the find. "Normally you only find a handful of bones, and the previous record was a 27 percent complete skeleton. With Dreadnoughtus we found 70 percent." 

Near-Complete: The reason near-complete finds are so rare is because fossilization requires a quick burial in sediment. As you can imagine, it's an extraordinary occurrence for something as big as a Dreadnoughtus to be buried so quickly. But according to Lacovara, the scientists believe a rapid pair of floods, caused by broken earthen levees in the valley where Dread was found, are behind the impressively complete find. Sedimentary records in nearby areas back up this idea.


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An Effective Filter for IBD Detection in Large Data Sets

An Effective Filter for IBD Detection in Large Data Sets | Paleomatica | Scoop.it
PLOS ONE: an inclusive, peer-reviewed, open-access resource from the PUBLIC LIBRARY OF SCIENCE. Reports of well-performed scientific studies from all disciplines freely available to the whole world.
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Paleontologists Discover Treasure Trove of Fossils at New Burgess Shale Site | I Fucking Love Science

Paleontologists Discover Treasure Trove of Fossils at New Burgess Shale Site | I Fucking Love Science | Paleomatica | Scoop.it
“ Canada is home to Burgess Shale: an expansive fossil field that contains a diverse array of preserved organisms dating all the way back to the Middle Cambrian, 505 million years ago. There are two well-known sites: one in the Yoho National Park and another 42 km (26 miles) away at Kootenay National Park. Another site has been discovered in Kootenay and could be the richest fossil site ever discovered. ”
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Giant mass extinction may have been quicker than previously thought

Giant mass extinction may have been quicker than previously thought | Paleomatica | Scoop.it
Boston MA (SPX) Feb 13, 2014 - The largest mass extinction in the history of animal life occurred some 252 million years ago, wiping out more than 96 percent of marine species and 70 percent of life on land - including the larges
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Human impact has pushed Earth into the Anthropocene, scientists say

Human impact has pushed Earth into the Anthropocene, scientists say | Paleomatica | Scoop.it
New study provides one of the strongest cases yet that the planet has entered a new geological epoch

 

Tags: Anthropocene, development,  land use, environment, environment modify.  


Via Seth Dixon, Verturner, Jim Lerman
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Sally Egan's curator insight, February 21, 2016 4:30 PM

Good discussion for syllabus dotpoint Human impacts on ecosystems within the HSC topic Ecosystems at Risk.

Andrea J Galan's curator insight, February 22, 2016 6:58 PM

I chose to add this article into my folder because it talks about earth entering a new geological epoch. This is exciting yet scary news because it's mostly pollution that justifies /proves the new epoch. The news is exciting because it's something that we are currently experiencing. The evidence that proves the geological epoch on the other hand is terrifying. It just goes to show how awful we have been treating our planet like if the next generation is going to be finding fossils in plastic bags that is a problem.

nukem777's curator insight, June 2, 2016 7:21 AM
Thought we were still officially in the Holocene...did I miss a memo?
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What’s that fossil? An app has answers.

What’s that fossil? An app has answers. | Paleomatica | Scoop.it

The Digital Atlas of Ancient Life is a free iOS app for iPhone and iPad that allows users to search for photos and information about fossils from three geological periods. It’s a completely packaged app that can be downloaded to a device and doesn’t require cell service for use—which can be handy in rural and remote locations, says Ohio University geologist Alycia Stigall.

 

Stigall and a team of Ohio University students contributed to the National Science Foundation-funded project by digitizing data on 30,000 specimens found in Ohio, Kentucky, and Indiana from the Ordovician Period, 443-453 million years ago.

 

Colleagues at San Jose State University and University of Kansas, which produced the app, provided data from the Pennsylvanian Period (300-323 million years ago) and the Neogene Period (23-2 million years ago). The app features data on about 800 species.

 

Many fossil specimens collected and described by scientists are housed in natural history museums or in laboratory drawers and are not accessible to the public, Stigall notes. But new software tools and apps now make it possible to digitize that information and put it in the hands of teachers, students, and backyard fossil enthusiasts, as well as the scientific community, she says.

 

The app is available at www.digitalatlastofancientlife.org.


Via Dr. Stefan Gruenwald
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Lynnette Van Dyke's curator insight, April 2, 2016 7:19 AM
Great application of digital technology.
Leonardo Wild's curator insight, April 2, 2016 11:27 AM
Great application of digital technology.
Renato P. dos Santos's curator insight, April 3, 2016 7:43 AM
What’s that fossil? A free off-line app has answers.
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Robotic dinosaurs on the way for next-gen paleontology at Drexel

Robotic dinosaurs on the way for next-gen paleontology at Drexel | Paleomatica | Scoop.it
Researchers at Drexel University are bringing the latest technological advancements in 3-D printing to the study of ancient life.

Articles about robotics: http://www.scoop.it/t/science-news?tag=robotics



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Did dinosaur-killing asteroid trigger largest lava flows Earth ever saw?

Did dinosaur-killing asteroid trigger largest lava flows Earth ever saw? | Paleomatica | Scoop.it

The asteroid that slammed into the ocean off Mexico 66 million years ago and killed off the dinosaurs probably rang the Earth like a bell, triggering volcanic eruptions around the globe that may have contributed to the devastation, according to a team of University of California, Berkeley, geophysicists.

 

Specifically, the researchers argue that the impact likely triggered most of the immense eruptions of lava in India known as the Deccan Traps, explaining the "uncomfortably close" coincidence between the Deccan Traps eruptions and the impact, which has always cast doubt on the theory that the asteroid was the sole cause of the end-Cretaceous mass extinction.

 

"If you try to explain why the largest impact we know of in the last billion years happened within 100,000 years of these massive lava flows at Deccan ... the chances of that occurring at random are minuscule," said team leader Mark Richards, UC Berkeley professor of earth and planetary science. "It's not a very credible coincidence."

 

Richards and his colleagues marshal evidence for their theory that the impact reignited the Deccan flood lavas in a paper to be published in The Geological Society of America Bulletin, available online today (April 30) in advance of publication.

 

While the Deccan lava flows, which started before the impact but erupted for several hundred thousand years after re-ignition, probably spewed immense amounts of carbon dioxide and other noxious, climate-modifying gases into the atmosphere, it's still unclear if this contributed to the demise of most of life on Earth at the end of the Age of Dinosaurs, Richards said.

 

Richards proposed in 1989 that plumes of hot rock, called "plume heads," rise through Earth's mantle every 20-30 million years and generate huge lava flows, called flood basalts, like the Deccan Traps. It struck him as more than coincidence that the last four of the six known mass extinctions of life occurred at the same time as one of these massive eruptions.

 

"Paul Renne's group at Berkeley showed years ago that the Central Atlantic Magmatic Province is associated with the mass extinction at the Triassic/Jurassic boundary 200 million years ago, and the Siberian Traps are associated with the end Permian extinction 250 million years ago, and now we also know that a big volcanic eruption in China called the Emeishan Traps is associated with the end-Guadalupian extinction 260 million years ago," Richards said. "Then you have the Deccan eruptions -- including the largest mapped lava flows on Earth -- occurring 66 million years ago coincident with the KT mass extinction.

 

Michael Manga, a professor in the same department, has shown over the past decade that large earthquakes -- equivalent to Japan's 9.0 Tohoku quake in 2011 -- can trigger nearby volcanic eruptions. Richards calculates that the asteroid that created the Chicxulub crater might have generated the equivalent of a magnitude 9 or larger earthquake everywhere on Earth, sufficient to ignite the Deccan flood basalts and perhaps eruptions many places around the globe, including at mid-ocean ridges.


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Deep-ocean microbe is closest living relative of complex cells

Deep-ocean microbe is closest living relative of complex cells | Paleomatica | Scoop.it

Scientists have discovered a microorganism that may bridge the gap between simple and complex cellular life forms. The discovery, reported in the journal Nature, will have far-reaching implications in our understanding of the evolution of life on Earth, including humans.

 

It’s one of the most significant, and most vexing, splits in life’s history. About 2 billion years ago, the prokaryotes, relatively simple single-celled organisms that include bacteria and archaea, gave rise to the more elaborate eukaryotes, the lineage that ultimately spawned multicellular life forms such as fungi, plants, and animals like us. Now, researchers combing through muck from the bottom of the North Atlantic Ocean have identified an archaeon that is the closest living relative of eukaryotes so far discovered.

 

The microbe, informally dubbed Loki and described this week in Nature, has set off a buzz among evolutionary biologists. “It tells us something very important about the origin of eukaryotes,” says Eugene Koonin of the National Center for Biotechnology Information in Bethesda, Maryland. “The ancestor of eukaryotes was a highly complex organism related to other archaea.” The deep-sea microbe “looks like a potential transitional form” that preserves one of the evolutionary steps between archaea and eukaryotes, adds evolutionary cell biologist Mark Field of the University of Dundee in the United Kingdom.

 

Unlike prokaryotes, eukaryotes sport organelles such as power-generating mitochondria and—in plants and some protists—light-capturing chloroplasts. Moreover, they stow DNA inside a nucleus that’s enclosed by a membrane, and their cells feature other internal structures built of membranes, such as the Golgi apparatus, lysosomes, and the endoplasmic reticulum.

 

Mitochondria and chloroplasts, researchers agree, are descended from formerly free-living prokaryotes that took up residence in other ancient cells. But the identity of the organism that captured and tamed those microbes remains unclear. Molecular evidence suggests that archaea are the closest relatives of eukaryotes. Researchers have disagreed, however, about whether eukaryotes branched off from a simpler prokaryote before archaea emerged—the traditional three-domain view of life—or evolved later, directly from archaea

 


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Genome analysis reveals that herders moved en masse from Russia to Central Europe around 4,500 years ago

Genome analysis reveals that herders moved en masse from Russia to Central Europe around 4,500 years ago | Paleomatica | Scoop.it

Analysis of the genomes of 69 ancient Europeans has revealed that herders moved en masse from Russia into Central Europe around 4,500 years ago. These migrants may be responsible for the expansion of Indo-European languages, which make up the majority of spoken tongues in Europe today.

 

Data from the genomes of 69 ancient individuals suggest that herders moved en masse from the continent's eastern periphery into Central Europe. These migrants may be responsible for the expansion of Indo-European languages, which make up the majority of spoken tongues in Europe today.

 

An international team has published the research in the journal Nature. Prof David Reich and colleagues extracted DNA from remains found at archaeological sites around the continent. They used a new DNA-enrichment technique that greatly reduces the amount of sequencing needed to obtain genome-wide data.

 

Their analyses show that 7,000-8,000 years ago, a closely related group of early farmers moved into Europe from the Near East, confirming the findings of previous studies. The farmers were distinct from the indigenous hunter-gatherers they encountered as they spread around the continent. Eventually, the two groups mixed, so that by 5,000-6,000 years ago, the farmers' genetic signature had become melded with that of the indigenous Europeans.

 

But previous studies show that a two-way amalgam of farmers and hunters is not sufficient to capture the genetic complexity of modern Europeans. A third ancestral group must have been added to the melting pot more recently.

 

Prof Reich and colleagues have now identified a likely source area for this later diaspora. The Bronze Age Yamnaya pastoralists of southern Russia are a good fit for the missing third genetic component in Europeans. The team analysed nine genomes from individuals belonging to this nomadic group, which buried their dead in mounds known as kurgans.

 

The scientists contend that a group similar to the Yamnaya moved into the European heartland after the invention of wheeled vehicles, contributing up to 50% of ancestry in some modern north Europeans. Southern Europeans on the whole appear to have been less affected by the expansion.


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Dinosaur-killer asteroid nearly wiped out mammals too

Dinosaur-killer asteroid nearly wiped out mammals too | Paleomatica | Scoop.it

The mass extinction event was thought to have paved the way for mammals to dominate, but researchers say many of them died out alongside the dinosaurs. During the Cretaceous period, extinct relatives of living marsupials – such as possums and kangaroos – thrived.

 

An international team of experts on mammal evolution and mass extinctions has shown that the once-abundant animals – known as metatherian mammals – came close to extinction. A 10-km-wide asteroid struck what is now Mexico at the end of the Cretaceous period, unleashing a global cataclysm of environmental destruction which led to the demise of the dinosaurs.

 

The study, including the University of Edinburgh scientists, shows that two-thirds of all metatherians living in North America also perished. This included more than 90 per cent of species living in the northern Great Plains of the US, which is the best area in the world for finding latest Cretaceous mammal fossils, researchers said.

 

Metatherians never recovered their previous diversity, which explains why marsupials are rare today and largely restricted to unusual environments in Australia and South America.

 

Species that give birth to well-developed live young – known as placental mammals – took full advantage of the metatherians’ demise. Placental mammals – which include many species from mice to men – are ubiquitous across the globe today, researchers said.

 

“This is a new twist on a classic story. It wasn’t only that dinosaurs died out, providing an opportunity for mammals to reign, but that many types of mammals, such as most metatherians, died out too – this allowed advanced placental mammals to rise to dominance,” said Dr Thomas Williamson from the New Mexico Museum of Natural History and Science.

 

Researchers reviewed the evolutionary history of metatherians and constructed the most up-to-date family tree for the mammals based on the latest fossil records, allowing them to study extinction patterns in unprecedented detail.


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Fossilized Nuclei and Chromosomes Reveal 180 Million Years of Genomic Stasis in Royal Ferns

Fossilized Nuclei and Chromosomes Reveal 180 Million Years of Genomic Stasis in Royal Ferns | Paleomatica | Scoop.it

It defies belief, but a 180 million year old fern fossil unearthed in Sweden is so exquisitely preserved that it is possible to see its cells dividing. So pristine is the fossil, reported scientists from the Swedish Museum of Natural History in the journal Science in March, that it is possible for them to estimate its genome size from the size of its cell nuclei — and that it has remained substantially unchanged from its living descendants since the early Jurassic.

 

The ferns were swallowed by a volcanic mudflow called a lahar, in which gas and rocky debris from an eruption mix with water and sediment. After entombment, hot salty water percolated into the coarse sediments around the ferns and acted as a preservative brine that immortalized the hapless plants. Their misfortune was our luck: 180 million years later, we can see details of their macro and micro anatomy so well that we can see how uncannily similar they are to their living descendants, royal and cinnamon ferns. They could be sisters!

 

Fossils from the family this fern belongs to had already been found from 220 million year-old rocks that were recognizable as the living species Osmunda claytonia — the interrupted fern — and other fossils from the Mesozoic have been found that are virtually indistinguishable from other genera and species in the fern’s family, the Osmundaceae (the royal ferns). But microscopic preservation of this quality has rarely been seen in any fossils before.


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Microscopic Diamonds Suggest Cosmic Impact Responsible for Younger Dryas Climate Change 12,800 Years Ago

Microscopic Diamonds Suggest Cosmic Impact Responsible for Younger Dryas Climate Change 12,800 Years Ago | Paleomatica | Scoop.it

A new study published in The Journal of Geology provides support for the theory that a cosmic impact event over North America some 13,000 years ago caused a major period of climate change known as the Younger Dryas stadial, or “Big Freeze.”

 

Around 12,800 years ago, a sudden, catastrophic event plunged much of the Earth into a period of cold climatic conditions and drought. This drastic climate change—the Younger Dryas—coincided with the extinction of Pleistocene megafauna, such as the saber-tooth cats and the mastodon, and resulted in major declines in prehistoric human populations, including the termination of the Clovis culture.

 

With limited evidence, several rival theories have been proposed about the event that sparked this period, such as a collapse of the North American ice sheets, a major volcanic eruption, or a solar flare.

 

However, in a study published in The Journal of Geology, an international group of scientists analyzing existing and new evidence have determined a cosmic impact event, such as a comet or meteorite, to be the only plausible hypothesis to explain all the unusual occurrences at the onset of the Younger Dryas period.

 

Researchers from 21 universities in 6 countries believe the key to the mystery of the Big Freeze lies in nanodiamonds scattered across Europe, North America, and portions of South America, in a 50-million-square-kilometer area known as the Younger Dryas Boundary (YDB) field.

 

Microscopic nanodiamonds, melt-glass, carbon spherules, and other high-temperature materials are found in abundance throughout the YDB field, in a thin layer located only meters from the Earth’s surface. Because these materials formed at temperatures in excess of 2200 degrees Celsius, the fact they are present together so near to the surface suggests they were likely created by a major extraterrestrial impact event.

 

In addition to providing support for the cosmic impact event hypothesis, the study also offers evidence to reject alternate hypotheses for the formation of the YDB nanodiamonds, such as by wildfires, volcanism, or meteoric flux.

 

The team’s findings serve to settle the debate about the presence of nanodiamonds in the YDB field and challenge existing paradigms across multiple disciplines, including impact dynamics, archaeology, paleontology, limnology, and palynology.

 


Via Dr. Stefan Gruenwald
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Bernhard H. Schmitz's curator insight, September 16, 2014 6:33 AM

And where is the center of the YDB field?

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PLOS ONE: an inclusive, peer-reviewed, open-access resource from the PUBLIC LIBRARY OF SCIENCE. Reports of well-performed scientific studies from all disciplines freely available to the whole world.
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