2013年3月14日雅思听力真题及解析（网友回忆）_第3页

　　填空题

　　The cave ecosystem in which troglobites reside can be divided in to 4 zones: . entrance, twilight, transition and deep cave.

　　31.Troglobites often have very low metabolisms to survive in a low oxygen environment where food is scarce because of their low metabolisms and sedentary life styles

　　32.1st animal live near cave entrance. Temperature is important

　　33.2nd animal live inside the caves. main factors: food supply, temperature and humidity.

　　34.They sometimes eat eggs

　　35.3rd animal live outside the caves affected by disease

　　36.Floodwater can be detrimental to troglobites species. Extreme winter temperatures are also intolerable.

　　37.Bird and bats in caves prey on troglobites.

　　38.Humans also pose a threat to them.

　　39.Pesticides and sewage from cities poison troglobites communities.

　　40.Scientific cave explorations can also harm these creatures.