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Wild ducks and other migratory (迁移的) birds could be important carriers of deadly bird flu, researchers say. Even so. the infectious-disease experts say there is no solid basis for killing wild birds to protect poultry and minimize the risk. of human infection.
The European team investigating the global spread of the It5N1 strain of avian influenza (禽流感) says certain duck species may be infecting wild bird populations. Geese and wading birds are also possible vectors (带菌者) of the virus, the team says.
The team’s study was led by Bjorn Olsen of Umea University in Sweden~ Olsen runs Europe’s largest wild-bird flu monitoring program.
Studies have shown that influenza viruses in lake water, generally passed via bird feces(粪), can stay infectious for up to 30 days. The migration or feeding behavior of dabbling ducks could at least partially explain the spread of the H5NI strain of bird flu, the researchers add.
This group of duc

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Wild ducks and other migratory (迁移的) birds could be important carriers of deadly bird flu, researchers say. Even so. the infectious-disease experts say there is no solid basis for killing wild birds to protect poultry and minimize the risk. of human infection.
The European team investigating the global spread of the It5N1 strain of avian influenza (禽流感) says certain duck species may be infecting wild bird populations. Geese and wading birds are also possible vectors (带菌者) of the virus, the team says.
The team’s study was led by Bjorn Olsen of Umea University in Sweden~ Olsen runs Europe’s largest wild-bird flu monitoring program.
Studies have shown that influenza viruses in lake water, generally passed via bird feces(粪), can stay infectious for up to 30 days. The migration or feeding behavior of dabbling ducks could at least partially explain the spread of the H5NI strain of bird flu, the researchers add.
This group of duc

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Mike found that young birds in isolation could only make some simple sound. Mike learned that a young bird has to hear other old birds’ song during the period before it is seven weeks old. Then there is a long time until the next spring before the bird begins to sing. And when it does start, it needs to practice before it finally gets the song right.
Further studies have proved that young birds do indeed need musical education. After several of the young birds raised in isolation were put together for about ten months, they learned from one another and finally could sing. The songs they sang, however, were quite different from the wild birds’. On the other hand, the young birds caught after their time was spent listening to the wild birds’ songs, knew how to sing.

Mike found the truth that（）
A. birds were born with the ability to sing
B. birds were born without the ability to sing
C. birds were born without the ability to make noises
D. birds were born without the ability to learn how to sing

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[单项选择]A. There were 2,200 Hawaii wild birds in 2003.
B. The number of the Hawaii wild bird has increased.
C. There have been 2,200 fewer Hawaii wild birds.
D. The number of Hawaii wild bird in 2008 is 1/3 of that in 2003.

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[单项选择]A. They could find more wild animals then.
B. The grass becomes yellow which is more beautiful.
C. There would be no mosquitoes stinging them.
D. There would be fewer insects.

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[填空题]Bites from skunks, raccoons, bats and other wild animals are less common, but more dangerous than bites from dogs, cats.

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[简答题]迁移

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[多项选择]In what other ways de you think market share could be increased (Why / Why not)

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The Evolution of Birds

Birds Began as Feathered Reptiles
Birds evolved during the great reptilian radiation of the Mesozoic era. Amniotic eggs and scales on the legs are just two of the reptilian features we see in birds. But modern birds look quite different from modern reptiles because of their feathers and other distinctive flight equipment.
Characteristics of Birds
Almost every part of a typical bird’s anatomy is modified in some way that enhances flight. The bones have an internal structure that is honeycombed, making them strong but light. The skeleton of a frigate bird, for instance, has a wingspan of more than 2 meters but weighs only about 113 grams. Another adaptation reducing the weight of birds is the absence of some organs. Females, for instance, have only one ovary. Also, modern birds are toothless, an adaptation that trims the weight of the head. Food is not
A. Square Ａ.
B. Square Ｂ.
C. Square Ｃ. D. Square Ｄ.

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