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Unformatted text preview: ing bird nests except the begging calls of nestling birds.
Paragraph 2在Further evidence for the costs of begging comes from a study of differences in the begging calls of warbler species that nest on the ground versus those that nest in the relative safety of trees. The young of ground
nesting warblers produce begging cheeps of higher frequencies than do their treenesting relatives. These higherfrequency sounds do not travel as far, and so may better conceal the individuals producing them, who are especially vulnerable to predators in their ground nests. David Haskell created artificial nests with clay eggs and placed them on the ground beside a tape recorder that played the begging calls of either treenesting or of groundnesting warblers. The eggs “advertised” by the treenesters' begging calls were found bitten significantly more often than the eggs associated with the groundnesters' calls.
3. The word artificial in the passage is closest in meaning to ○ attractive
○ not real
○ well designed
4. Paragraph 2 indicates that the begging calls of tree nesting warblers ○ put them at more risk than groundnesting warblers experience
○ can be heard from a greater distance than those of groundnesting warblers
○ are more likely to conceal the signaler than those of groundnesting warblers
○ have higher frequencies than those of ground nesting warblers
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5. The experiment described in paragraph 2 supports which of the following conclusions? ○ Predators are unable to distinguish between the begging cheeps of groundnesting and those of tree
nesting warblers except by the differing frequencies of the calls. ○ When they can find them, predators prefer the eggs of treenesting warblers to those of groundnesting warblers.
○ The higher frequencies of the begging cheeps of groundnesting warblers are an adaptation to the threat that groundnesting birds face from predators ○ The danger of begging depends more on the frequency of the begging cheep than on how loud it is.
Paragraph 3 在 The hypothesis that begging calls have evolved properties that reduce their potential for attracting predators yields a prediction: baby birds of species that experience high rates of nest predation should produce softer begging signals of higher frequency than nestlings of other species less often victimized by nest predators. This prediction was supported by data collected in one survey of 24 species from an Arizona forest, more evidence that predator pressure favors the evolution of begging calls that are hard to detect and pinpoint .
6. The word prediction in the passage is closest in meaning to ○ surprise
7. The word pinpoint in the passage is closest in meaning to ○ observe
○ locate exactly
○ copy accurately
Paragraph 4 在 Given that predators can make it costly to beg for food...
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This note was uploaded on 09/17/2013 for the course LANGUAGE 13DL208 taught by Professor Wang during the Fall '13 term at East China Normal University.
- Fall '13