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CANBERRA, Aug. 17 (Xinhua) -- Australian scientist on Wednesday said his international research team has discovered the trick on how butterfly learn to change its wing pattern to avoid being eaten by birds.The Amazonian butterfly, Heliconius numata, has learnt to carry out a single genetic switch to alter its wing pattern so it appears to be another bad-tasting butterfly that birds will avoid.Dr. Siu Fai (Ronald) Lee from the Department of Genetics and Bio21 Institute at Australia's University of Melbourne was part of the international research team, which was led by scientists at Centre National de la Recherche Scientifique (CNRS) and the University of Exeter in United Kingdom.Dr. Lee said the historical mystery had puzzled researchers for decades."Charles Darwin was puzzled by how butterflies evolved such similar patterns of warning coloration," Dr. Siu Fai (Ronald) Lee from the Department of Genetics and Bio21 Institute at the University of Melbourne told Western Australia Today."We have now solved this mystery, identifying the region of chromosome responsible for changing wing pattern."He said the research team identified a genetic switch known as a supergene, which allowed the butterfly to morph into several different forms, allowing one species to mimic another."It is amazing that by changing just one small region of the chromosomes, the butterfly is able to fool its predators by mimicking a range of different butterflies that taste bad," he said."The butterflies rearrange this supergene DNA like a small pack of cards, and the result is new wing patterns. It means that butterflies look completely different but have the same DNA."There are other butterflies doing similar tricks, but this is the most elegant one."I was just fascinated by how elegant they were."He said the discovery proves that small chromosomal changes can preserve successful gene combinations, and thus help a species to adapt.The findings of the study are published on August 14 in the international journal Nature.

SAN FRANCISCO, Aug. 10 (Xinhua) -- Amazon on Wednesday launched Kindle Cloud Reader, a web-based app that may help the on-line retailer to sidestep Apple's App Store restrictions.In its announcement, Amazon said Kindle Could Reader uses the HTML5 web standard to let users read e-books from their Kindle library from the Safari browser or Google's Chrome browser on their desktops or tablet, including the iPad.Support for Internet Explorer, Firefox and the Blackberry Playbook will be launched later this year.The app has a button linked to the Kindle Store, which was removed recently from the Kindle apps for iPad and iPhone.The move is taken as an answer to Apple's latest App Store restrictions, which banned developers to have any external links for purchasing digital books or subscriptions in the app, unless they give Apple a 30 percent cut from the in-app sales.Besides Amazon, Barnes & Noble, Google Books and Canadian e- book seller Kobo have also altered their iPad and iPhone apps to comply with the rules.Meanwhile, publishers and retailers have been developing web- based HTML5 apps to sidestep Apple for more control, which is an approved-of technology for iOS devices.The Financial Times, Kobo and video-on-demand service Vudu have recently launched their HTML5 app to avoid paying Apple a 30 percent cut.Industry watchers said it is unknown how Apple will deal with such apps. It would be easy for Apple to disable Web apps in the iPad's Safari browser, but the company would certainly face some backlash, said tech media website CNET.

VIENNA, Sept. 22 (Xinhua) -- Climate change and rising temperature in the long term can lead to water shortages in the Alps region, international experts warned Thursday at the Water-Scarce Final Conference in the Austrian eastern city Graz.The Alpine region originally is rich in water resources due to a large number of glaciers, spring and abundant rainfall either in summer or winter. But global warming may change this situation which has been shown in the past years that the water reserve has reduced gradually due to climate change, warned the experts.Observation data have shown a significant decrease of 25 percent in groundwater recharge in the past 100 years which has also resulted in the reduction of mountain spring.Director of the Provincial Department of Water Resources of Styria Johann Wiedner point out, in 2003, droughts occurred in the eastern part of the Alps, including the state of Styria and water shortages were also found in other regions of the Alps. He said the phenomenon was giving a warning that people "have to do something."To this end, the European Union begun a project called "Alp Water Scarce" three years ago to observe water reserves, air temperature, water temperature and water table in this region and study the relationships among them.Wiedner also admitted that there is no shortage of water at least in the short term and water supply for the local residents is totally insured.

BEIJING, Sept. 6 (Xinhuanet) -- Scientists from Tufts University of the U.S. have created the world's smallest electrical motor in a single molecule.The finding was published in the journal Nature Nanotechnology on Monday.In the research, scientist successfully made a single molecule accept an electrical charge and rotate as fast as 120 revolutions per second."This is the first time that electrically-driven molecular motors have been demonstrated, despite a few theoretical proposals," said Charles H. Sykes, professor of chemistry at Tufts who led the team.The single molecule electric motor could lead to new types of electrical circuitry, giving hope for scientists to apply it in medicine and engineering, he said."The next thing to do is to couple it to other molecules, lining them up next to one another so they're like miniature cog-wheels, and then watch the rotation propagation down the chain," said Sykes.

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