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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.

LOS ANGELES, June 8 (Xinhua) -- NASA's Mars Exploration Rover Opportunity is heading toward "Spirit Point" on the rim of a large crater, a long-term destination that the rover has been trying to reach for nearly three years, the Jet Propulsion Laboratory (JPL) announced on Wednesday.Opportunity has moved toward the crater, Endeavour, since climbing out of Victoria crater in August 2008.Having driven 11 miles (18 kilometers), the rover has about two miles (about three kilometers) to go before reaching the rim of Endeavour, said JPL in Pasadena, Los Angeles.Rover team members last week selected "Spirit Point" as the informal name for the site on the rim where Opportunity will arrive at Endeavour crater. The choice commemorates Opportunity's rover twin, Spirit, which has ended communication and finished its mission."Spirit achieved far more than we ever could have hoped when we designed her," said Steve Squyres of Cornell University, Ithaca, New York, principal investigator for the rovers. "This name will be a reminder that we need to keep pushing as hard as we can to make new discoveries with Opportunity. The exploration of Spirit Point is the next major goal for us to strive for."Endeavour offers the setting for plenty of productive work by Opportunity. The crater is 14 miles (22 kilometers) in diameter -- more than 20 times wider than Victoria crater, which Opportunity examined for two years. Orbital observations indicate that the ridges along its western rim expose rock outcrops older than any Opportunity has seen so far. Spirit Point is at the southern tip of one of those ridges, "Cape York," on the western side of Endeavour.Opportunity and Spirit completed their three-month prime missions on Mars in April 2004. Both rovers continued for years of bonus, extended missions. Both have made important discoveries about wet environments on ancient Mars that may have been favorable for supporting microbial life.NASA's JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Exploration Rover Project for the NASA Science Mission Directorate, Washington.

SAN FRANCISCO, Sept. 6 (Xinhua)-- Yahoo on Tuesday fired Chief Executive Officer Carol Bartz and replaced her temporarily with the company's chief financial officer."On behalf of the entire board, I want to thank Carol for her service to Yahoo during a critical time of transition in the company's history, and against a very challenging macro-economic backdrop," said Yahoo Chairman Roy Bostock in a news release.The Yahoo Board of Directors appointed CFO Timothy Morse as interim CEO who will manage the company's day-to-day operations until a permanent chief executive is chosen.Carol Bartz, chief executive of Internet company Yahoo Inc, is shown in this undated publicity photo released to Reuters January 13, 2009. Before Yahoo's formal announcement, several news organizations and tech blogs posted an email reportedly from Bartz sent from her iPad to all employees of the company."To all, I am very sad to tell you that I've just been fired over the phone by Yahoo's Chairman of the Board. It has been my pleasure to work with all of you and I wish you only the best going forward."Bartz, 63, took over the Yahoo CEO role from co-founder Jerry Young in January 2009, when the company was struggling to stay competitive and profitable in a market dominated by Google. However, Yahoo never reached the heights she had foreseen.In the most recent quarterly earnings report in June, Yahoo reported net revenue of 1.1 billion U.S. dollars, down 5 percent from last year.Morse, 42, was hired as executive vice president and CFO at Yahoo in July 2009. "It is an honor to be selected for this role," he said in a statement Tuesday.Yahoo said it is starting a search for a new permanent CEO and plans to hire a "nationally recognized executive search firm" to assist in the effort.

CANBERRA, Sept. 1 (Xinhua) -- Bushranger Ned Kelly's headless body has finally been identified in Australia, more than 130 years after his execution in the Old Melbourne Gaol, Victoria's Attorney- General Robert Clark announced on Thursday.Clark said the bushranger's remains have been identified by doctors and scientists at the Victorian Institute of Forensic Medicine (VIFM).Kelly was an Irish Australian bushranger, considered by some merely a cold-blooded killer, while by others a folk hero and symbol of Irish Australian resistance against oppression by the British ruling class for his defiance of the colonial authorities. He was hanged for murder in 1880 at Old Melbourne Gaol. His daring and notoriety made him an iconic figure in Australian history, folklore, literature, art and film.The project involved collaboration with the ancient DNA laboratory EAAF in Argentina, which has worked with the VIFM on other forensic projects.Clark said "This is an extraordinary achievement by our forensic team here in Victoria," he told reporters in Melbourne on Thursday."To think a group of scientists could identify the body of a man who was executed more than 130 years ago, moved and buried in a haphazard fashion among 33 other prisoners, most of whom are not identified, is amazing." The investigation started when a skull believed to belong to Kelly was handed to the VIFM on Nov. 11, 2009.The skull handed in in 2009 was found not to be that of Ned Kelly, and Glenrowan historian Gary Deans said the next step is to find Kelly's skull."The Government should put a request in the public arena for the return of Ned Kelly's skull," he told ABC News."We know thanks to Jack Cranston, who held the skull around 1929, that it was sitting on a detective's desk. This was around the same time that remains were dug up in the Old Melbourne Gaol."I imagine that that detective or somebody else took it home."

CAIRO, July 4 (Xinhua) -- U.S. and Italian archeologists have discovered the oldest description about an Egyptian king (about 3, 200 BC) in Egypt's Aswan, Egyptian Antiquities Minister Zahi Hawass said on Monday.The engravings "traces back to when the Egyptian language firstly recorded in hieroglyphs and tells about a unique complete royal ceremony which was known in the ancient Egyptian era," said Hawass in a statement."The pharaoh appears to be wearing the Upper Egypt crown accompanied by (Horus apostles) at the royal court, " Hawass added.Horus is one of the oldest and most significant deities in the ancient Egyptian religion and was worshipped from at least the late Predynastic period through to Greco-Roman times."This discovery is considered a supplementary one at the site unearthed near in el-Hamdulab site in northern Aswan, archaeologists said.This is one of the latest discoveries in Egypt as the surrounding wall of Betah temple (1550 BC-1070 BC) and a gate traces back to Shabaka king era were unearthed on Saturday in Luxor.

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