African crocodiles

文章大意

讲座围绕尼罗鳄（Crocodylus niloticus）展开，讲其狭长吻部、背部三到四排鳞片等特征，以及作为食肉动物的生活习性、非洲境内集中分布于南部和西部、北非撒哈拉为何没有鳄鱼、 Mauritania 湿地中46条鳄鱼成群（float）的观察，还提到冷血动物体温约38摄氏度。

题目与答案

1. 31 The student thought there were no crocodiles in Northern Africa because
   • North Africa contains very little wildlife for the crocodile to prey on
   • she found no mention in the literature of their existence there
   • there is very little water in North Africa

   答案：she found no mention in the literature of their existence there

   原文定位：This student noticed that on the map displaying the distribution of crocodiles across Africa, there were no crocodiles in the northern region and found no mention in the literature of the existence of crocodiles in the north of Africa

2. 32 Generally crocodiles live in groups of about
   • 20
   • 38
   • 46

   答案：20

   原文定位：received reports of forty-six crocodiles living in one group;Though the usual number is a little less than half of that

3. 33 African crocodiles usually in areas with
   • hot and dry climates
   • hot and wet rainforest
   • warm and wet climates

   答案：warm and wet climates

   原文定位：In general, crocodiles are more highly concentrated in wet, subtropical environments near bodies of water and rich vegetation;While South American crocodiles thrive in cool rainforests, the African crocodile is more equipped for heat

   同义替换：「warm」↔「more equipped for heat」

4. 34 Crocodiles in dry areas live in caves located
   • underground
   • in mountainsides
   • underwater

   答案：underground

   原文定位：these desert crocodiles dig underground caves that collect runoff, thus staying cool and hydrated

   同义替换：「dry areas」↔「desert」，「live in caves」↔「dig underground caves」

5. 35 What change caused changes in crocodile populations in North Africa?
   • They were driven away by a fierce predator
   • Crocodiles evolved from desert creatures to wetland creatures
   • North Africa used to be wetland but slowly turned to desert over time

   答案：North Africa used to be wetland but slowly turned to desert over time

   原文定位：About eight thousand years ago, the land was fertile wetlands, perfect for breeding crocodiles. Over time, though, the area dried out and the wetland slowly turned to desert, leading the African crocodile to migrate south

6. Desert crocodiles sometimes live in places with dry periods that last up to 36_____ months.

   答案：eight

   原文定位：In Mauritania, some crocodiles have learned to survive in an area where they can go up to eight months with no water

   同义替换：「dry periods」↔「with no water」，「last up to」↔「go up to」

7. A hole dug by a female crocodile in which to lay eggs can have a 37_____ of up to 60cm.

   答案：depth

   原文定位：the female digs a hole up to sixty centimeters in depth to store the eggs for an eighty-day incubation period

   同义替换：「lay」↔「store」

8. Local people are not 38_____ crocodiles.

   答案：afraid of

   原文定位：Although these vicious creatures have attacked humans on a few occasions, the residents are not afraid of them

   同义替换：「Local people」↔「residents」

9. Crocodiles 39_____ out of fear when humans populate their habitat.

   答案：attack

   原文定位：They attack when humans populate the crocodile's habitat, instilling fear and uneasiness in the crocs. Like any other species, crocodiles are known to attack when feeling fear

10. Researchers want to study more about population size, 40_____ , and relations to other populations of crocodiles.

    答案：migration patterns

    原文定位：There is still also much to learn about migration patterns and relations to other populations of crocodiles now found in other parts of the world

    同义替换：「study」↔「learn」