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[b]Due to length limits in this forum, this is just the first part of this posting. You can find the whole thing [url=http://www.msb-science.com/ScienceNews/Science-Current-Events-2017Feb26.pdf]here[/url]. [/b]
[b][url=http://www.msb-science.com/ScienceNews/Science-Current-Events-2017Feb26.pdf]http://www.msb-science.com/ScienceNews/Science-Current-Events-2017Feb26.pdf[/url] [/b]
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[b][color=black][size=4]Life Science[/size][/color][/b]
[i][size=4]Australian cathedral termites[/size][/i]
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[color=#494949][size=3]In proportion to their size, termites build some of the tallest non-human structures in the world -- equivalent to humans building a structure eight times as tall as the Empire State Building. Now it's been discovered that the termites that live in Australia's remote Top End originated from overseas -- rafting vast distances and migrating from treetops to the ground, as humans later did. Referred to as "cathedral" termites, the [i]Nasutitermes triodiae[/i] build huge mounds up to eight meters high. DNA sequencing found that their forebears, called nasute termites, colonized Australia three times in the past 20 million years and evolved from wood- to grass-feeding as they adapted to significant environmental changes, including increasingly arid conditions and the conversion of woodlands to grassland habitats in subtropical savannahs in central Australia.[/size][/color]
[url=https://www.sciencedaily.com/releases/2017/02/170221220642.htm]https://www.sciencedaily.com/releases/2017/02/170221220642.htm[/url] [size=2] [/size]
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[b][color=black][size=4]Earth Science [/size][/color][/b]
[i][size=4]New data on history of Pacific Ring of Fire [/size][/i]
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[size=3]About 2000 kilometers east of the Philippine Islands lies one of the most famous topographical peculiarities of the oceans: the Mariana trench. Reaching depths of up to 11,000 meters below sea level, it holds the record as the deepest point of the world's ocean. This 4000-kilometer-long trench extends from the Mariana Islands in the south through the Izu-Bonin Islands to Japan in the north. Here, the Pacific Plate is subducted beneath the Philippine Sea Plate, resulting in intense volcanic activity and a high number of earthquakes. The entire area is part of the "Pacific Ring of Fire. But when and how exactly did the subduction of the Pacific Plate begin? To investigate this, a drill core was obtained, providing samples of rocks that originate from the first stages of subduction. Researchers were able to drill more than 1600 meters deep on the seabed, starting at a water depth of around 4700 meters below sea level. This is already at the limit of what is technically feasible. Based on analysis of this drill core, the researchers were able to trace the history of the subduction zone layer by layer up to the approximately 50 million year-old rocks at the bottom of the core. The researchers found evidence that volcanism was only beginning to gain momentum. The volcanic activity intensified with the rollback of the subduction zone towards the east and the huge explosive stratovolcanoes* formed, similar to those present nowadays, for example along the western rim of the Pacific Ring of Fire. There will be much more to be learned from further drilling.[/size]
[url=https://www.sciencedaily.com/releases/2017/02/170210130921.htm]https://www.sciencedaily.com/releases/2017/02/170210130921.htm[/url] [size=2] [/size]
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[size=2]*A stratovolcano, also known as a composite volcano, is a conical volcano built up by many layers of hardened lava, rock fragments, pumice, and volcanic ash.[/size]
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[b][color=black][size=4]Climate Change [/size][/color][/b]
[i][color=#191e2b][size=4]Melting sea ice speeding nature's clock in the Arctic [/size][/color][/i]
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[size=3][font=Cambria]Spring is coming sooner to some plant species in the low Arctic of Greenland, while other species are delaying their emergence amid warming winters. The changes are associated with diminishing sea ice cover, according to researchers. The timing of seasonal events, such as first spring growth, flower bud formation and blooming make up a plant's phenology -- the window of time it has to grow, produce offspring, and express its life history. Think of it as "nature's clock." In the Arctic, nature's clock is running fast. The research shows that warming winters and springs associated with declining arctic sea ice cover created a mixture of speed demons, slowpokes, and those in between. One sedge species now starts out a full 26 days earlier than it did a decade ago. This was the greatest increase in the timing of emergence on record in the Arctic.[/font]
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