問題詳情

Questions 10-19The most thoroughly studied cases of deception strategies employed by ground-nestingbirds involve plovers, small birds that typically nest on beaches or in open fields, theirnests merely scrapes in the sand or earth. Plovers also have an effective repertoire of tricksLine for distracting potential nest predators from their exposed and defenseless eggs or chicks.(5) The ever-watchful plover can detect a possible threat at a considerable distance. Whenshe does, the nesting bird moves inconspicuously off the nest to a spot well away fromeggs or chicks. At this point she may use one of several ploys. One technique involvesfirst moving quietly toward an approaching animal and then setting off noisily throughthe grass or brush in a low, crouching run away from the nest, while emitting rodent like(10) squeaks. The effect mimics a scurrying mouse or vole, and the behavior rivets theattention of the type of predators that would also be interested in eggs and chicks.Another deception begins with quiet movement to an exposed and visible location wellaway from the nest. Once there, the bird pretends to incubate a brood. When the predatorapproaches, the parent flees, leaving the false nest to be searched. The direction in which(15) the plover "escapes" is such that if the predator chooses to follow, it will be led still furtheraway from the true nest.The plover's most famous stratagem is the broken-wing display, actually a continuumof injury-mimicking behaviors spanning the range from slight disability to near-completehelplessness. One or both wings are held in an abnormal position, suggesting injury. The(20) bird appears to be attempting escape along an irregular route that indicates panic. In themost extreme version of the display, the bird flaps one wing in an apparent attempt totake to the air, flops over helplessly, struggles back to its feet, runs away a short distance,seemingly attempts once more to take off, flops over again as the "useless" wing fails toprovide any lift, and so on. Few predators fail to pursue such obviously vulnerable prey.Needless to say, each short run between "flight attempts" is directed away from the nest.
10. What does the passage mainly discuss?
(A) The nest-building techniques ofplovers
(B) How predators search for plovers
(C) The strategies used by plovers todeceive predators
(D) Why plovers are vulnerable topredators

參考答案

答案：C
難度：非常簡單1
統計：A(0),B(0),C(4),D(0),E(0)

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