Module 4 课时达标训练(十六)
Ⅰ.阅读理解
More than two thirds of the world's polar bears will be wiped out by 2050, according to a shocking new study. By then, scientists say，global warming will have melted 42 percent of the Arctic sea ice. By 2100, only a very few of these important creatures will be left.
The report has been produced by the US Geological Survey. The scientists have publicized their findings in the hope of influencing US Interior Secretary Dirk Kempthorne, who has been asked to put polar bears on the US endangered species list.
Polar bears depend on floating sea ice as a platform for hunting seals, which are their main food. Without enough ice, polar bears would be forced to go onto the land, where they are poorly skilled hunters, and would be unlikely to adapt to the life on the land in time. Experts say few little bears would survive and the stress could make many females unable to get pregnant.
The team of American and Canadian scientists spent six months studying bears，on the ground，from spotter
