# Nocturnal animals - 科目：雅思听力真题（Part 4） - 考频：中频 - 最近考试：2025.3.8 - 题目数：10 - 来源页：https://www.yaquan.site/paper/28c29ddc-0359-46f0-a8ea-b73ae2ae98a7（在线机考练习与音频请访问该页面） - 数据更新：2026-10-29 ## 题目原文 00:00:00,180 Part four. You will hear a lecture about nocturnal animals. First, you have some times to look at questions thirty-one to forty. Listen carefully and answer questions thirty-one to forty. 00:00:12,540 Good morning, everyone. 00:00:14,680 Today, I will discuss the fascinating world of nocturnal animals, focusing on the adaptations that enable them to thrive in darkness. 00:00:24,420 Many species have evolved unique features to help them survive and avoid competition or predation at night. 00:00:31,860 To begin, one of the most notable evolutionary trends among nocturnal species is the loss of certain organs that are no longer needed. 00:00:41,520 Over time, some animals have developed alternative ways to navigate and interact with their surroundings, making specific body parts redundant. 00:00:51,480 A great example is the cave crab, which has completely lost its eyes. 00:00:57,160 Since it resides in deep, dark environments where light is scarce, vision is unnecessary, and instead, these crabs rely on other senses to detect movement and find food. 00:01:09,580 This is just one example of how nature optimizes an animal's physiology according to its environment. 00:01:16,880 Now, let's turn our attention to a nocturnal mammal that exhibits several remarkable adaptations, the two-toed sloth. 00:01:26,120 Unlike its three-toed counterpart, this species has a far more varied diet. The key reason for this is that it forages primarily at night, which allows it to avoid competing with other animals for food resources. 00:01:40,620 As a result, two-toed sloths have access to a wider range of plant species and even some small animals, unlike their more restricted relatives. 00:01:51,000 Another crucial adaptation in two-toed sloths is their highly flexible head, which allows them to observe their environment more effectively. 00:02:00,620 Unlike many other mammals, these sloths can rotate their heads at a much greater angle, providing them with a broader field of vision. 00:02:09,720 This increased mobility is advantageous in detecting predators and potential threats, even in dense forest environments. 00:02:18,940 Additionally, these animals possess the ability to regulate their body temperature based on surrounding conditions. 00:02:27,100 Unlike many mammals that maintain a constant internal temperature, two-toed sloths can adjust theirs depending on factors such as humidity and ambient temperature. This helps them conserve energy, which is essential to survival given their slow metabolic rate. 00:02:46,000 Furthermore, a rather unusual but effective form of camouflage assists them in blending into their habitat. Their fur hosts algae, which give it a greenish tint, allowing them to merge seamlessly with tree foliage. This mutualistic relationship benefits both organisms. The sloth gains improved concealment from predators, while the algae receive shelter and nutrients from the sloth's fur. 00:03:14,740 Moving on, let's discuss another nocturnal species, the North Island brown kiwi, which has developed distinct adaptations to survive in its habitat. 00:03:25,220 This bird has evolved to be active at night primarily to evade predators, particularly a species of eagle that once posed a significant threat to it. 00:03:35,860 By becoming nocturnal, kiwis minimize encounters with these formidable hunters and improve their chances of survival. 00:03:44,320 Interestingly, kiwis do not rely much on vision as their eyes are poorly adapted for detailed sight, especially when it comes to perceiving colors. 00:03:55,060 Unlike many birds that use their eyesight to locate food, kiwis compensate with an exceptional sense of smell. 00:04:03,180 Their nostrils are located at the tip of their long beaks, a rare feature among birds, allowing them to detect insects and worms hidden beneath the soil. 00:04:14,200 This heightened olfactory ability is a crucial survival tool in the darkness. 00:04:20,000 Another surprising trait of kiwis is the size of their eggs. 00:04:24,680 When compared to their body proportions, kiwi eggs are exceptionally large. In fact, a single egg can take up about twenty percent of the mother's body, making it one of the most disproportionate egg sizes in the animal kingdom. 00:04:40,280 This unusual adaptation ensures that kiwi chicks hatch in a well-developed state, giving them a better chance of surviving in the wild. 00:04:50,300 Finally, let's turn our attention to bats, the only mammals capable of sustained flight. One of their most remarkable adaptations is the presence of specialized skin on their ears, which enhances their ability to use echolocation. 00:05:07,260 Bats emit high-frequency sounds that bounce off objects, allowing them to interpret the returning echoes and navigate through complete darkness. 00:05:17,920 This skill is especially crucial for hunting flying insects, which they track with astonishing precision. 00:05:25,760 An additional fascinating feature of bats relates to their sleeping posture. 00:05:31,420 Unlike most animals that rest on solid ground, bats sleep while hanging upside down. 00:05:38,100 This is made possible because their claws remain securely hooked onto surfaces due to gravity. 00:05:44,880 Unlike human hands, which require muscle effort to grip objects, bats' tendons naturally lock in place, ensuring that they do not fall while resting. This efficient mechanism enables them to conserve energy and remain safely out of reach of predators. 00:06:03,900 In conclusion, nocturnal animals have developed an array of specialized traits that allow them to thrive in environments where others struggle. Whether it's losing unnecessary organs, adjusting metabolism, or relying on echolocation, these adaptations highlight the incredible diversity and resilience of life in the natural world. ## 题目与答案 ### 31. Evolutionary Adaptations · Some nocturnal animals lose certain 31_____ over time due to lack of necessity. Evolutionary Adaptations · Some nocturnal animals lose certain 31_____ over time due to lack of necessity. **答案**：organs 原文定位：To begin, one of the most notable evolutionary trends among nocturnal species is the loss of certain organs that are no longer needed 同义替换：「due to lack of necessity」↔「no longer needed」 ### 32. Three-toed Sloth · they have a varied 32_____ compared to their three-toed relatives because they face less competition at night. Three-toed Sloth · they have a varied 32_____ compared to their three-toed relatives because they face less competition at night. **答案**：diet 原文定位：Unlike its three-toed counterpart, this species has a far more varied diet. The key reason for this is that it forages primarily at night, which allows it to avoid competing with other animals for food resources 同义替换：「compared to their three-toed relatives」↔「Unlike its three-toed counterpart」；「face less competition」↔「avoid competing with other animals for food resources」 ### 33. · Their flexible 33_____ allows them to scan their surroundings efficiently. · Their flexible 33_____ allows them to scan their surroundings efficiently. **答案**：head 原文定位：Another crucial adaptation in two-toed sloths is their highly flexible head, which allows them to observe their environment more effectively 同义替换：「scan their surroundings」↔「observe their environment」 ### 34. · These sloths adjust their 34_____ depending on environmental conditions. · These sloths adjust their 34_____ depending on environmental conditions. **答案**：temperature 原文定位：Additionally, these animals possess the ability to regulate their body temperature based on surrounding conditions 同义替换：「environmental」↔「surrounding」；「adjust」↔「regulate」 ### 35. · The presence of algae in their 35_____ helps them blend into their environment. · The presence of algae in their 35_____ helps them blend into their environment. **答案**：fur 原文定位：Their fur hosts algae, which give it a greenish tint, allowing them to merge seamlessly with tree foliage 同义替换：「algae in their fur」↔「fur hosts algae」；「blend into their environment」↔「merge seamlessly with tree foliage」 ### 36. Kiwis and Bats · North Island brown kiwis adapted to a nocturnal lifestyle to escape 36_____ . Kiwis and Bats · North Island brown kiwis adapted to a nocturnal lifestyle to escape 36_____ . **答案**：eagle 原文定位：This bird has evolved to be active at night primarily to evade predators, particularly a species of eagle that once posed a significant threat to it 同义替换：「adapted to a nocturnal lifestyle」↔「evolved to be active at night」；「escape」↔「evade」 ### 37. · Their eyesight lacks the ability to perceive 37_____ but they have an excellent sense of smell. · Their eyesight lacks the ability to perceive 37_____ but they have an excellent sense of smell. **答案**：colors 原文定位：Interestingly, kiwis do not rely much on vision as their eyes are poorly adapted for detailed sight, especially when it comes to perceiving colors 同义替换：「lacks the ability to」↔「poorly adapted for」 ### 38. · The 38_____ laid by kiwis are unusually larger in proportion to their size. · The 38_____ laid by kiwis are unusually larger in proportion to their size. **答案**：eggs 原文定位：Another surprising trait of kiwis is the size of their eggs. When compared to their body proportions, kiwi eggs are exceptionally large 同义替换：「unusually larger in proportion to their size」↔「exceptionally large compared to their body proportions」 ### 39. · Bats have specialized 39_____ skin for echolocation. · Bats have specialized 39_____ skin for echolocation. **答案**：skin 原文定位：One of their most remarkable adaptations is the presence of specialized skin on their ears, which enhances their ability to use echolocation ### 40. · Bats rely on 40_____ to keep their claws secure while sleeping. · Bats rely on 40_____ to keep their claws secure while sleeping. **答案**：gravity 原文定位：This is made possible because their claws remain securely hooked onto surfaces due to gravity 同义替换：「rely on」↔「due to」；「keep their claws secure」↔「claws remain securely hooked onto surfaces」 --- 以上内容由鸭圈雅思真题库（www.yaquan.site）提供，收录近期雅思考试真题回忆，支持在线机考模式免费练习。