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根据下面资料，回答题 Endangered Species Reading: Polar Bear Makes the List
In Spring 2008, the polar bear was placed on the endangered species list. According to the Endangered Species Act, an endangered species is an animal that is likely to face extinction in its natural habitat. 26 The ESA defines a threatened species as one that is likely to become "endangered" in the foreseeable future.
The polar bear is the first animal that has been classified as endangered due primarily to globalwarming. 27 Heating homes, driving cars, and burning garbage all require fossil fuels that lead toglobal warming.
The polar bear' s habitat is more vulnerable to global warming than many other species. Polarbears live mainly on the sea ice in the Arctic.28 When the ice melts many polar bears move toland and live off their stored fat. In the Arctic, global warming is causing the ice to melt slightly earlierand form slightly later. This results in a shorter feeding season for the polar bear. Some risk their livesto find ice. If they have to swim too far they will drown from exhaustion and hunger.
29 Every species of plant, animal, and insect there is threatened by global warming. Nevertheless, environmentalist groups such as the World Wildlife Fund often study large carnivores in orderto assess the health of an ecosystem (生态系统).30 In addition, donations are more commonlyoffered for the protection of large animals such as bears or elephants. People in general are lessinterested in conservation efforts that protect small wildlife, such as plants or insects. However, byusing donor money to protect the habitat of the larger animals ( ex. reforestation programs ) , entireecosystems can be protected.
It is important that animals such as the polar bear make it onto the endangered species list.Once they are on the list there are laws that protect these animals from being hunted for food orsport. Agencies also receive money and tools to protect the habitat and recover the species. The goalof removing the animal from the list is often achievable. In fact, it is rare for a species to go extinctafter they make the list. Sadly many species do go extinct while waiting for consideration.
A. But adding polar bears to the nation' s list of endangered species, as some are now proposing,should not be part of those efforts.
B. Global warming is caused by carbon dioxide and other greenhouse gases that become trapped inthe atmosphere.
C. The Arctic food chain relies on the polar bear.
D. It is not only the polar bear that is at risk in the Arctic.
E. This is where they hunt for fish and build up fat reserves.
F. Polar bears have been categorized as a "threatened" species.
第（26）题选
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