题目

阅读理解     It's a real case of fish out of water. Blennies (鲇鱼) in the South Pacific Ocean are gradually relocating to land to escape their predators (捕食者), in an example of evolution in action.     Fish first began crawling onto dry land about 400 million years ago, kicking off an evolutionary chain of events that led to humans. But their reasons for exiting the sea have been uncertain.     To look for clues, Terry Ord at the University of New South Wales in Australia has been studying several species of blennies at Rarotonga, the largest of the Cook Islands.     At low tide, blennies are commonly found swimming in rock pools around the edges of the island. But when high tide moves in, they climb up to dry land and move around the rocks until the tide retreats.     The researchers found that this is most likely to avoid predators that swim in with the rising tide – mainly bigger fish like lionfish.     To test what would happen if blennies did not have an escape plan, they made blenny models and sank them in the sea. The mimics ended up with wounds, bite marks and chunks-missing.     Of course, there are still dangers for blennies on land, like the occasional bird attack, but the predation risk on land is a third that of underwater.     What's more, moving onto land has additional benefits for blennies. Holes in the rocks provide sheltered nests for laying eggs, and they can maintain their diet of bacteria.     In fact, several species of blenny fish at Rarotonga have already made the full transition to land-dwelling (陆生的) species. They continue to breathe with their gills, but have developed stronger tail fins and jump from rock to rock.     Ord believes that many evolutionary processes have been driven by the need to escape predators. “It is often assumed that animals move homes to find new sources of food, but in many cases, escaping predators is a stronger motivation.” he says. （1） Why do blennies climb to dry land when high tide comes? A . To acquire better health. B . To search for more food. C . To seek safer living conditions. D . To adapt to a new environment. （2） What does the underlined part “The mimics” in Paragraph 6 refer to? A . The rocks in the water. B . The predators of blennies. C . The researchers of blennies. D . The models of blennies. （3） What can be concluded from the last paragraph? A . Ord's research opens a new view. B . Ord wonders why animals move homes. C . Ord shows us the benefits of blennies' evolution. D . Ord has discovered how fish have become land dwellers. （4） Which of the following could be the best title for the text? A . Blennies' Living Habits B . Why Blennies Choose to Live on Land C . Blennies' Evolutionary Process D . How Blennies Escape from their Predators 答案： C D A B

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