未来的现实生活中或出现巨型老鼠
Rats that are the size of sheep might be a good horror movie story. However, scientists from the University of Leicester in England say that in the future, there could really be giant rats on the Earth. Rats now can weigh about 1kg. They could be as big as sheep and weigh up to 80 times in the future.
Rats are spreading all over the Earth. They are now the strongest animals on many small islands. One of the reasons for this is that they travel on ships and relocate to areas that never had rats before. Another reason is that many larger animals are becoming extinct, so there are fewer animals that might kill rats. Researcher Dr Jan Zalasiewicz said, “Given enough time, rats could probably grow to be the world’s largest rodent(啮齿动物).”
Dr Zalasiewicz said rats are one of the best examples of a species that have spread around the world, and have successfully adapted to many of the new environments. He said, “There will be future thin rats, future fat rats, slow and heavy rats, fast and ferocious(凶猛的) rats, probably future aquatic(水生的) rats—the list goes on.”
After the dinosaurs died out, many small animals slowly grew bigger and bigger. The same thing could happen with rats if there are no animals left that hunt and kill them. Dr Zalasiewicz also believes that “super-rats” will start killing other species to make them extinct. This will have a big impact on food chains. He did not say what humans would do about giant rats running around everywhere.
1.How much does a sheep probably weigh?
A 1kg.
B 80kg.
C 40kg.
D 20kg
解析：选B。B 推理判断题。根据第一段“Rats now can weigh about 1kg. They could be as big as sheep and weigh up to 80 times in the future.”可知现在的老鼠可以达到 1 公斤，未来它们可能和绵羊一样大，体重可达到现在的 80 倍，即 80 公斤，故推测一只绵羊大约重 80 公斤，故选 B。
2.Why did Zalasiewicz say rats would grow to be the world’s largest rodent?
A Larger animals are getting older.
B There are more food for them.
C Rats are lager than before.
D They have fewer enemies.
解析：选D。D 细节理解题。根据第二段可知，老鼠在地球上蔓延，它们现在是许多小岛上最强壮的动物，它们迁到以前从没有老鼠的地区，另外很多大型动物灭绝，老鼠少了许多天敌，选项 D 最符合文意，故选 D。
3.According to Zalasiewicz, rats are _________.
A well-adapted
B brave enough
C very different
D badly trained
解析：选A。A 推理判断题。根据第三段“and have successfully adapted to many of the new environments” 可 知 Zalasiewicz 认为老鼠的对环境的适应性很强，故 选 A。
4.What happened after the dinosaurs died out?
A The food chains were impacted.
B Rats make other species disappear.
C No animals that hunt and kill rats were left.
D Some animals became bigger and bigger.
解析：选D。D 细节理解题。根据最后一段“After the dinosaurs died out, many small animals slowly grew bigger and bigger.”可知恐龙灭绝后，很多小型动物越长越大。故选 D。
5.Where can we most probably read this passage?
A In a life magazine.
B In a movie review.
C In a travel guide.
D In a history book.
解析：选A。A 文章出处题。全文围绕未来现实生活中的老鼠可能会长大成巨型老鼠展开，结合选项可知最可能出现在生活杂志上，故选 A。