Algae and pollen grains reveal sudden spike in Antarctica's temperature 15.7 mln yrs ago.Washington, October 1 (ANI): A team of scientists has found evidence in the form of algae algae (ăl`jē) [plural of Lat. alga=seaweed], a large and diverse group of primarily aquatic plantlike organisms. These organisms were previously classified as a primitive subkingdom of the plant kingdom, the thallophytes (plants that and pollen grains of a sudden, remarkably warm period in Antarctica that occurred about 15.7 million years ago and lasted for a few thousand years. The evidence was found by Sophie Warny, LSU (Louisiana State University Louisiana State University and Agricultural and Mechanical College, generally known as Louisiana State University or LSU, is a public, coeducational university located in Baton Rouge, Louisiana and the main campus of the Louisiana State University System. ) assistant professor of geology and geophysics and curator at the LSU Museum of Natural Science, and colleagues. Last year, as Warny was studying samples sent to her from the latest Antarctic Geologic Drilling Program, or ANDRILL AND-2A, a multinational collaboration between the Antarctic Programs of the United States, New Zealand, Italy and Germany, one sample stood out as a complete anomaly. "First I thought it was a mistake, that it was a sample from another location, not Antarctica, because of the unusual abundance in microscopic fossil cysts of marine algae called dinoflagellates dinoflagellates minute aquatic protozoa; they produce red pigment and toxins which are taken up by shellfish without apparent ill effect, but the toxin is not metabolized and the shellfish may poison animals if eaten. . But it turned out not to be a mistake, it was just an amazingly rich layer," said Warny. Some colleagues had noted an increase in pollen grains of woody plants in the sample immediately above, but none of the other samples had such a unique abundance in algae, which at first gave Warny some doubts about potential contamination. "But the two scientists in charge of the drilling, David Harwood of University of Nebraska - Lincoln, and Fabio Florindo of Italy, were equally excited about the discovery," said Warny. "They had noticed that this thin layer had a unique consistency that had been characterized by their team as a diatomite, which is a layer extremely rich in fossils of another algae called diatoms diatoms a series of unicellular algae, microscopic in size, with cell walls containing silica. Members of the family Diatomaceae. Their remains accumulate as geological deposits and are mined. See diatomaceous earth. ," he added. All research parties involved met at the Antarctic Research Facility at Florida State University Florida State University, at Tallahassee; coeducational; chartered 1851, opened 1857. Present name was adopted in 1947. Special research facilities include those in nuclear science and oceanography. in Tallahassee. Together, they sampled the zone of interest in great detail and processed the new samples in various labs. One month later, the unusual abundance in microfossils was confirmed. Among the 1,107 meters of sediments recovered and analyzed for microfossil mi·cro·fos·sil n. A microscopic fossil, as of a pollen grain or unicellular organism. microfossil A microscopic fossil, as of a pollen grain or unicellular organism. Noun 1. content, a two-meter thick layer in the core displayed extremely rich fossil content. This is unusual because the Antarctic ice sheet The Antarctic ice sheet is one of the two polar ice caps of the Earth. It covers about 98% of the Antarctic continent and is the largest single mass of ice on Earth. The total ice mass on the Earth covers an area of almost 14 million square km and contains 30 million cubic km of was formed about 35 million years ago, and the frigid temperatures there impede the presence of woody plants and blooms of dinoflagellate dinoflagellate Any of numerous one-celled, aquatic organisms that have two dissimilar flagella and characteristics of both plants (algae) and animals (protozoans). Most are microscopic and marine. algae. "We all analyzed the new samples and saw a 2,000 fold increase in two species of fossil dinoflagellate cysts, a five-fold increase in freshwater algae and up to an 80-fold increase in terrestrial pollen," said Warny. "Together, these shifts in the microfossil assemblages represent a relatively short period of time during which Antarctica became abruptly much warmer," he added. (ANI) Copyright 2009 Asian News International The Asian News International (ANI) agency provides multimedia news to China and 50 bureaus in India. It covers virtually all of South Asia since its foundation and presently claims, on its official website, to be the leading South Asia-wide news agency. (ANI) - All Rights Reserved. Provided by Syndigate.info an Albawaba.com company |
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