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China fossil biota reveals post-extinction seafloor 445 mln years ago

A cluster of exceptionally-preserved fauna fossils has been found in east China's Zhejiang Province, it was announced today.
The fossils may help scientists understand more about the seabed in the period around a mass extinction event that occurred at the end of the Ordovician period, which was around 443-445 million years ago.

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Brachiopod
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Ancient Marine Animal Is Evolving Genetically Despite Little Change in Appearance

A group of scientists from Okinawa Institute of Science and Technology Graduate University (OIST), Nagoya University, and the University of Tokyo decoded the first lingulid brachiopod genome, from Lingula anatina collected at Amami Island, Japan.
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Conodonts
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An extinct primitive marine vertebrate had the sharpest dental structures ever known -- with tips just one-twentieth of the width of a human hair, but able to apply pressures that could compete easily with those from human jaws.
The razor-sharp teeth belonged to conodonts, jawless vertebrates that evolved some 500 million years ago in the Precambrian eon and went extinct during the Triassic period, around 200 million years ago. The creatures roamed the planet for longer than any other vertebrate so far-- and despite their lack of jaws, they were the first creatures to evolve teeth.

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Humble moss helped to cool Earth and spurred on life

Primitive moss-like plants could have triggered the cooling of the Earth some 470 million years ago, say researchers.
A study published in Nature Geoscience may help explain why temperatures gradually began to fall, culminating in a series of "mini ice ages".
Until now it had been thought that the process of global cooling began 100 million years later, when larger plants and trees emerged.

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First plants caused ice ages

Research originated at the University of East Anglia and the John Innes Centre has revealed how the arrival of the first plants 470 million years ago triggered a series of ice ages.
Scientists, now based at the Universities of Exeter and Oxford, set out to identify the effects that the first land plants had on the climate during the Ordovician Period, which ended 444 million years ago. During this period the climate gradually cooled, leading to a series of 'ice ages'. This global cooling was caused by a dramatic reduction in atmospheric carbon, which this research, published in Nature Geoscience, now suggests was triggered by the arrival of plants.

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Late Ordovician conodont fauna
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Title: First Late Ordovician conodont fauna in the Betic Cordillera (South Spain): a palaeobiogeographical contribution
Authous: R. Rodriguez-Canero, A. Martin-Algarra, G. N. Sarmiento, P. Navas-Parejo

The youngest Ordovician conodont fauna in SW Europe has been found in the Malaguide Complex of the Betic Cordillera, SE Spain. It is also the first Ordovician conodont fauna in the Western Mediterranean Alpine Orogen. The conodont association, attributed to the Hirnantian (upper part of the Amorphognathus ordovicicus Biozone), is characterized by the predominance of Walliserodus amplissimus and Scabbardella altipes and by the absence of Sagittodontina and Istorinus, typical of the Mediterranean Province. This fauna differs markedly from those of the same biozone recorded in the Spanish Variscan Orogen of the Iberian Massif, which are attributed to the Katian. The Malaguide fauna shows, however, striking similarity to faunas of the Carnic Alps and some resemblance to those of the Pyrenees, Northern England and North Wales. These features suggest that Palaeozoic terranes of the Betic Cordillera were located far to the east of their present location and displaced westward during the Alpine Orogeny.



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Descubiertos los fósiles más antiguos de la Cordillera Bética

Investigadores españoles han hallado por primera vez en el Mediterráneo occidental fósiles de conodontos del Ordovícico de entre 446 y 444 millones de años de antigüedad. El hallazgo de estos vertebrados marinos muy primitivos ha contribuido a la reconstrucción de la paleogeografía de la Cordillera Bética. Según el estudio, en esa época el sistema montañoso del sur de la Península Ibérica se situaba junto a los Alpes.
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The Oldest Soft-Bodied Fossils from the Ordovician

Paleontologists have discovered a rich array of exceptionally preserved fossils of marine animals that lived between 480 million and 472 million years ago, during the early part of a period known as the Ordovician. The specimens are the oldest yet discovered soft-bodied fossils from the Ordovician, a period marked by intense biodiversification. The findings, which appear in the May 13, 2010 issue of the journal Nature, greatly expand our understanding of the sea creatures and ecosystems that existed at a crucial point in evolutionary history, when most of the animal life on the planet was found in the oceans.
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 Whenever you visit a beach resort or sea side town, you will also find plenty of sea shells for sale. But a group of scientists went looking in a very different location
They were rewarded with the discovery of marine fossils in land locked Sichuan province. The fossils are the remains of ancient sea life from nearly 500 million years ago.
The fossils were discovered on the western slope of Jinbo Mountain, which stands 2,250 meters above sea level. They are scattered around an area of one square kilometre. All are embedded in rocks. Experts believe they were remains of ancient sea life in the Ordovician period.
The Ordovician period began approximately 490 million years ago, and ended around 443 million years ago. At this time, the area north of the tropics was almost entirely ocean, and most of the world's land was collected into a southern super-continent called Gondwana.
The Ordovician period is best known for its diverse marine invertebrates, including graptolites, trilobites, brachiopods, and conodonts, which were a form of early vertebrates.
The end of the Ordovician period witnessed a mass extinction, cited as the second most devastating extinction to marine life in history. It caused the disappearance of one third of all brachiopod and bryozoan families.

Source CCTV.com


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