今天讀pbt中的一片閲讀的文章時突然發現0108中的這篇文章 和12.15的一片聼力很像
應該是其中的一部分把
聽力機經：lecture 鸟类通过自己的行为吸引 predator,保护自己的子女 或弱者有问题问你通过什么方式吸引 predator。 一种是假装翅膀受伤，一种是装成另外一种动物在地上跑（例如老鼠）。鸟类的这种表现也有不同level，最强的level出现在lay eggs 一段时间之后。
0108
Questions 10-19
The most thoroughly studied cases of deception strategies employed by ground-nesting
birds involve plovers, small birds that typically nest on beaches or in open fields, their
nests merely scrapes in the sand or earth. Plovers also have an effective repertoire of tricks
Line 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. When
she does, the nesting bird moves inconspicuously off the nest to a spot well away from
eggs or chicks. At this point she may use one of several ploys. One technique involves
first moving quietly toward an approaching animal and then setting off noisily through
the 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 the
attention 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 well
away from the nest. Once there, the bird pretends to incubate a brood. When the predator
approaches, 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 further
away from the true nest.
The plover's most famous stratagem is the broken-wing display, actually a continuum
of injury-mimicking behaviors spanning the range from slight disability to near-complete
helplessness. 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 the
most extreme version of the display, the bird flaps one wing in an apparent attempt to
take 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 to
provide 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.
谢谢！！
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