NATOINAL GEOGRAPHIC
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Tiny Fossils Reveal Warm Antarctic Past
Hundreds of fossils of crustacean-like animals no bigger than a pinhead have been found in Antarctica, scientists say. The 14-million-year-old called ostracods were found recently in an ancient lake bed in the Dry Valleys region in the continent's interior.
The well-preserved fossils are likely the last remnants of a warmer Antarctica, before a massive and intense climate cooling millions of years ago set in, new research suggests. (Read: "Ancient Seal Remains Reveal Warmer Antarctica, Study Says" [June 26, 2006].) "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 [east] Antarctic ice sheet," study lead author Mark Williams, a geologist with the University of Leicester, said in a statement. "[It's] a key factor in understanding the effects of global warming," Williams added. The findings were published Wednesday in Proceedings of the Royal Society B. Tiny Relics Study co-authors Adam Lewis and David Marchant, along with a Boston University team, were looking for volcanic ash in 2006 when they discovered deposits in the remnants of a now-dry glacial lake. Processing the deposits back in the lab at North Dakota State, undergraduate student Rich Thomasson first noticed the fossils, which are shaped like footballs. "Essentially the whole soft parts of the creature were preserved," including its tiny walking legs and tail, said study co-author Allan Ashworth, a paleontology professor at North Dakota State University. The discovery marked only the fourth time in the world that the soft anatomy of such a fossil had been preserved between the two valves that connect its body, he added.
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Sundog Light Phenomenon, Manitoba, Canada, 2005
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Swiftcurrent Creek
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