Figure of the fossil ostracod from the Dry Valleys. The specimen is less than 1 mm long, but preserves an array of soft tissues including legs and mouth parts.
Posted on 08/06/2008 12:18:53 AM PDT by neverdem
Figure of the fossil ostracod from the Dry Valleys. The specimen is less than 1 mm long, but preserves an array of soft tissues including legs and mouth parts.
A new fossil discovery- the first of its kind from the whole of the Antarctic continent- provides scientists with new evidence to support the theory that the polar region was once much warmer.
The discovery by an international team of scientists is published today (**Embargoed until 00.01 BST Wednesday 23 July**) in Proceedings of the Royal Society B. It involved researchers from the University of Leicester, North Dakota State University, the British Geological Survey, Queen Mary University of London, and Boston University.
The team made a new fossil discovery in the Dry Valleys of the East Antarctic region. The fossils (ostracods) come from an ancient lake - 14 million years old - and are exceptionally well preserved, with all of their soft anatomy in 3-dimensions.
Dr Mark Williams from the Department of Geology at the University of Leicester said: "This is a rare occurrence in the fossil record - but is the first of its kind from the whole of the Antarctic continent.
"Notwithstanding the significance of the fossil preservation, the presence of lake ostracods at this latitude, 77 degrees south, is also of great note. Present conditions in this Antarctic region show mean annual temperatures of minus 25 degrees C. These are impossible conditions to sustain a lake fauna with ostracods."
"The fossils therefore show that there has been a substantial and very intense cooling of the Antarctic climate after this time interval that is important for tracking the development of the Antarctic icesheet – a key factor in understanding the effects of global warming.
"The fossil ostracods of the Dry Valleys signal a high latitude lake viable for animal colonisation that indicates a dramatic change in the climate of this region, from tundra conditions 14 million years ago, to the intensely cold continental interior climate experienced today."
The researchers point out that there is no evidence to suggest the fossil discovery points to a once widespread Antarctic lake ostracod fauna: "It is most likely their introduction was by chance, perhaps via birds as dispersal of ostracod eggs attached to the feathers or feet of migratory birds is an important influence on modern ostracod distribution."
The ostracods were discovered by Richard Thommasson, an undergraduate student, during screening of the sediment in Prof. Allan Ashworth's lab at North Dakota State University.
Source : University of Leicester
Neat!
The diatom record indicates that Palaeolake Boreas was long lived (Ashworth et al. 2007). Restriction of the ostracods to a single horizon implies that their colonization was serendipitous, and that the lake was only temporarily viable.
Relatively rapid change? Or else they were on the edge as it was? The fact that they pyritized indicates low organic carbon and lots of reactive iron, so perhaps it wasn't a temperature change that killed them off...?
The ostracods were discovered by Richard Thomasson, an undergraduate student, during screening of the sediments in Ashworth’s laboratory at North Dakota State University.
Cool! I love it when undergrads make discoveries!
The details are extraordinary...Exceptionally, sub-micrometer-scale details such as setae and wrinkles are preserved as external moulds by coarse-grained coatings, but such resolution is typically associated with replacements by microcrystalline fabrics.
Global cooling sucks.
there are seams of coal in antartica 100’s of feet thick,,the place was tropical for millions of years
Not Miocene.
And so the paleoglacial deposits were just put there by God to fool us into thinking there were previous ice ages?
Global warming from Paleozoic SUV’s?
perhaps by the same birds that once sat in the trees
that left their stumps in the ground 
and fossilized bark 
and leaves...after the birds flew back to where they migrated from?
Paleontologists from the United States and Argentina discovered one of the most complete plesiosaur skeletons ever found. (A plesiosaur is a swimming marine reptile that lived about 70 million years ago. At that time the waters of what is now Antarctica were much warmer than they are today.) The fossil plesiosaur was discovered during a 2005 expedition to Antarctica. The fossil goes on display today at the South Dakota School of Mines and Technology's Museum of Geology.
This plesiosaur specimen is a juvenile of about 5 feet (1.5 meters) in length. An adult plesiosaur is about 32 feet (10 meters). It was perfectly articulated and complete, except that the skull had been lost to erosion. The plesiosaur was excavated from deposits of shallow marine sands covered by volcanic ash. Paleontologists speculate that the volcanic blast or debris thrown into the ocean was responsible for the plesiosaur's death...
Artist's impression of the plesiosaur and environment. Painting by Nicolle Rager, National Science Foundation.
Fighting . . . urge . . . to make . . . H.P. Lovecraft reference . . . here . . . .
Oh, God! I hope not. /s
Yes. And furthermore, the ONLY REASON WE HAVE ICE AGES is that we currently have a landmass at one of the poles.
If Antarctica was next to France then the world would be warmer.
Global cooling; the earth is freezing. We’re ALL GONNA DIE!
Look on the bright side. When global warming converts the terperate zones to furnaces, we can all move to Antarctica.
Protection has more people packing heat
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related:
Ancient Vegetation, Insect Fossils Found in Antarctica
Fox News
Posted on 08/05/2008 9:56:54 AM PDT by Scythian
http://www.freerepublic.com/focus/f-news/2056891/posts
http://www.physorg.com/news137089101.html
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