[简答题]Passage 2
Endangered Species Endangered species are plants and animals that are in immediate danger of extinction. Extinction is actually a normal process in the course of evolution. Since the formation of the earth, many more species have become extinct than those exist today. These species slowly disappeared because of changes of climate and their failure to adapt to such conditions as competition and predation (捕食). Since the 1600s, however, the process of extinction has greatly accelerated as a result of both human population growth and technological encroachment (侵犯) on natural ecology systems. Today the majority of the world’s environments are changing faster than the ability of most species to adapt to such changes through natural selection.
Species become extinct or endangered for a number of reasons, but the primary cause is the destruction of natural habitats (栖息地). Drainage of wetlands (沼泽地), cutting and clearing of forests, growth of cities, and highway A. A.Worried B.Optimistic C.Indifferent D.Confident