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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, Sept. 13 (Xinhua) -- Microsoft released on Tuesday a test version of Windows 8 to developers, posing to regain ground of the tablet market dominated by Apple and Google.At its developer-focused BUILD conference held in Anaheim, California, the software giant handed out new Samsung tablet computers with a test version of the code-named "Windows 8," the first detailed preview of the system for developers and people outside Microsoft.Generally expected to be launched in fall 2012, Microsoft did not say when the system will ship or its price.Microsoft Windows President Steven Sinofsky introduces the new tablet running a test version of its touch-enabled Windows 8 at the Build conference in Anaheim, California September 13, 2011Featuring a home page filled with colorful application tiles, the new system boots up in seconds. Microsoft said the system will run on low-power ARM-based chips that power smartphones and tablets. Windows 8 also introduces a new "Metro style" interface, which run full-screen and users can multitask in two at a time."We reimagined Windows," said Steven Sinofsky, president of the Windows and Windows Live Division at Microsoft, in his keynote address to the thousands of developers in attendance. "From the chipset to the user experience, Windows 8 brings a new range of capabilities without compromise."Analysts said the new system is consumer-oriented and intuitive but it will take time to see whether it is an "iPad killer."As professionals and consumers began to spend more time on smartphones and tablets, Microsoft has not got a significant bite of the market, losing ground to Apple's iPad and devices running Google's Android system.

SAN FRANCISCO, Aug. 15 (Xinhua) -- Facebook and Yahoo on Monday started to test "six degrees of separation," an iconic social experiment in the 1960s that showed everyone is on average approximately six steps away from any other person on earth.The current Facebook-Yahoo "small world" experiment, based on more than 750 million active Facebook users, is expected to determine the social path length between two strangers.Anyone with a Facebook account can participate by going to smallworld.sandbox.yahoo.com and will be assigned a "target person. " The participant will be asked to select one of his or her Facebook friends, whom will be forwarded a message and then pass the message from friend to friend so that the participant will get a message to the "target person" in as few steps as possible.The study is intended as academic social research and will be published in peer-reviews scientific journal, Duncan Watts, Yahoo' s principal research scientist who is leading the experiment, told San Jose Mercury News.In the 1960s, American social psychologist Stanley Milgram and other researchers conducted several experiments to examine the average path length for social networks of people in the United States, suggesting that human society is a small world type network by around 5.5 people steps or about six people on average.It is now currently accepted that there were potential flaws in the so-called "small world experiment" because the conclusions were based on relatively small number of research samples.

BEIJING, June 7 (Xinhuanet) -- Sony Corp. on Monday unveiled its next generation portable gaming device, PlayStation Vita.The new PlayStation Vita will go on sale for 249 U.S. dollars, or 299 dollars for a 3G mobile version, starting in the holiday season, the Japanese electronics giant's No. 2 executive Kazuo Hirai told reporters on the eve of the E3 games convention.The device will allow gamers to be connected with one another over cellphone networks and Wi-Fi hotspots, and use GPS location-tracking technology. In the U.S., Sony is partnering exclusively with AT&T Inc. for cellphone service.Company executives have called the device Sony's biggest product launch since the PlayStation 3 five years ago."PlayStation Vita will revolutionize the portable entertainment experience," said Hirai. "The whole world is really in play."The handheld has front and back cameras, a touchscreen in front, a touch pad on the back and two knob-like joysticks. It will enable gamers to play against people using PlayStation 3 consoles over the Internet-based PlayStation Network.

BEIJING, Sept. 10 (Xinhua) -- China will start "overall and thorough" safety checks on offshore oil exploration and production to eliminate risks in the wake of oil spills in the country's northern Bohai Bay, the work safety authority said Saturday.The checks, which starts from September 10 to December 10, will be applied to all offshore oil exploration and production, the State Administration of Work Safety said in a circular addressed to oil companies on its website.The companies include China National Petroleum Corporation, China Petrochemical Corporation, China National Offshore Oil Corporation, ConocoPhillips China, Kerr-McGee China Petroleum Ltd., Roc Oil (Bohai) Company, CACT Operators Group, Husky Oil China Ltd., Shanghai Petroleum Co., Energy Development Corporation (EDC) China and Tincy Group Energy, the statement said.The administration urged these enterprises to conduct self-examinations on their offshore fixed and mobile platforms and floating production storage and offloading units, submarine pipelines and onshore oil terminals in two months till November 10. They should file result reports before November 20.The authority's officials, joined by experts, will launch inspections from late November, the statement said. The checks cover well control amid drilling operation, safety management during production, facilities, and management over extreme weather, it added.The order came after the State Council on Wednesday called for strengthened monitoring and management of the marine environment as well as safety checks over the country's ocean oil fields to toughen safety measures and erase potential risks.The decision was made after oil spills at an offshore oil field run by U.S. oil giant ConocoPhillips have polluted more than 5,500 square km of sea water in the Bohai Bay since June.The central government also imposed restricts on new petrochemical projects and ban reclamation projects in the bay for environmental concerns.China has stepped up efforts to explore and materialize offshore resources to seek more dependence of the marine industries as a strategic development move. In its 12th Five-Year Plan, the government advocates greater scientific and systematic utilization of marine resources and coastal areas as energy demand soars.