The problem with animals waking up early, or skipping hibernation altogether, lies with the creatures’ metabolism(新陈代谢). When the animals hibernate, their metabolism drops significantly. The animals’ heart rate slows, and they require very little energy to live. When the animals awake from their winter slumber, their metabolism returns to normal.

　　But while their metabolism may be as active as it was before hibernation, food sources aren’t as available as they were before. A marmot may wake up when temperatures get warmer, thinking it’s spring, but plants will not have got the amount of sun they need to signal their spring period of growth. So until the plants grow, the marmots have no reliable food source.

　　Many scientists believe the problem will continue to get worse. In addition to changes in hibernation patterns, some believe that other animals will also begin to change their migration patterns or begin to give birth earlier. For many biologists, that’s a scary prospect. Terry Root, an animal expert at Stanford University, said, “I do think what we will be facing is the extinction of many species. ”

　　【文章大意】全球变暖带来的连锁反应是多方面的, 其中之一就是导致一些冬眠动物的冬眠期缩短, 这会给这些动物带来巨大的影响。

　　1. What is the viewpoint of the writer?

　　A. Global warming will continue to get worse as time goes on.

【2017届高考英语（牛津译林版）一轮复习课时提升作业：(十四) 必修5 Unit 2 The Environment】相关文章：

★ 【浙江专用】2014届高考英语一轮复习课时作业(二十三)必修5Unit 3《Life in the future》

★ 2017届高考英语二轮复习书面表达限时测验：2（含解析）

★ 四川省2016届高考英语一轮复习课时作业（46） Module 4 Which English 外研版选修8

★ 2014届高考英语一轮复习课时作业(三十四)选修6Module 4《Music》（外研版）

★ 2017届高考英语二轮复习课时训练：1（含解析）

★ 【浙江专用】2014届高考英语一轮复习课时作业(一)必修1Unit 1《Friendship》

★ 2014届高考英语一轮复习课时作业(七)必修2Module 1《Our Body and Healthy Habits》（外研版）

★ 【三维设计】2017届高考英语（江苏专用）二轮复习课件：必修3 Unit 3《Back to the past》

★ 2014届高考英语一轮复习课时作业(三十二)选修6Module 2《Fantasy Literature》（外研版）

★ 2014届高考英语一轮复习课时作业(四十八)选修8Module 6《The Tang Poems》（外研版）