[請益] TPO11 Begging by Nestling Q5

[Bonniepei (樂翻天唷)]

Paragraph 2：
  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
tree-nesting relatives. These higher-frequency 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 tree-nesting or of
ground-nesting warblers. The eggs “advertised” by the tree-nesters'
begging calls were found bitten significantly more often than the eggs
associated with the ground-nesters' calls.



5. The experiment described in paragraph 2 supports which of the following
conclusions?
○ Predators are unable to distinguish between the begging cheeps of
ground-nesting and those of tree-nesting warblers except by
the differing frequencies of the calls.
○ When they can find them, predators prefer the eggs of tree-nesting
warblers to those of ground-nesting warblers.
○ The higher frequencies of the begging cheeps of ground-nesting warblers
are an adaptation to the threat that ground-nesting birds face from predators
○ The danger of begging depends more on the frequency of the begging cheep
than on how loud it is.


答案是C


為什麼不能選A呢

A選項的意思 是不是 Predator 能分辨不同頻率的聲音，無法區分地上鳥巢和樹上鳥巢


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◆ From: 123.192.25.47
推 Cando:地上鳥巢比較不安全，所以幼鳥用較高頻率的叫聲比較不會被
→ Cando:predator找到
→ azcactus:A:這段裡面沒有說到掠食者'有沒有能力'分辨不同鳥的叫聲
→ azcactus:進一步看，掠食者是能夠區分的，但是A選項的except太武斷