US bees operation keeping groups have been attacked seriously by so called Colony （群体）Collapse Disorder．Almost 1/2 of their worker bees have vanished during the past season．This disorder has also been reported in Israel, Europe and South America．Bees fly away from the hive and never return．Sometimes they are found dead; other times they are never found．Many crops and trees depend on pollination^^}） by bees to help them grow． A new report says a virus may be at least partly responsible for the disorder in honey bee colonies in the United States．This virus is called Israeli acute paralysis virus．It was first found in Israel in 2004．lan Lipkin at Columbia University in New York and a team reported the new findings in Science Magazine．Doctor Lipkin says the virus may not be the only cause．He says it may work with other causes to produce the collapse disorder． The team found the virus in colonies with the help of a map of honey bee genes that was published last year．They examined thirty colonies affected by the disorder．They found evidence of the virus in twenty-five of them, and in one healthy colony．The next step is further testing of healthy hives． The researchers suggested that the United States may have imported the disorder in bees from Australia．They say the bees may carry the virus but not be affected． The idea is that unlike many American bees, the ability of Australian bees to fight disease has not been hurt by the varroa mite．This insect attacks honey bees, which could make the disorder more likely to affect a hive．Australian bee producers object to these suspicions． And some researchers suspect that bee production in the United States is down mainly because of the weather．Honey bees gather nectar from flowers and trees．The sweet liquid gives them food and material to make honey．But cold weather this spring in the Midwest reduced the flow of nectar in many flowers．Many bees may have starved．Dry weather in areas of the country could also be playing apart． Wayne Esaias is a NASA space agency scientist who keeps bees in his free time．He lives in central Maryland, where he has found that flowers are blooming a month earlier than they did in 1970, which may be partly responsible for the disorder. Wayne Esaias is organizing a group of beekeepers to document nectar flow around the country. 小题1:What is the author’s attitude toward the cause of this disorder?
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