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题库 / Prep2007E1-CR-24
Tiger beetles are such fast runners that they can capture virtually any nonflying insect. However, when running toward an insect, the beetles intermittently stop, and then, a moment later, resume their attack. Perhaps they cannot maintain their pace and must pause for a moment's rest; but an alternative hypothesis is that while running tiger beetles are unable to process the resulting rapidly changing visual information, and so quickly go blind and stop.
Which of the following, if discovered in experiments using artificially moved prey insects, would support one of the two hypotheses and undermine the other?
When a prey insect is moved directly toward a beetle that has been chasing it, the beetle immediately turns and runs away without its usual intermittent stopping.
In pursuing a moving insect, the beetles usually respond immediately to changes in the insect's direction, and pause equally frequently whether the chase is up or down an incline.
The beetles maintain a fixed time interval between pauses, although when an insect that had been stationary begins to flee, the beetle increases its speed after its next pause.
If, when a beetle pauses, it has not gained on the insect it is pursuing, the beetle generally ends its pursuit.
When an obstacle is suddenly introduced just in front of running beetles, the beetles sometimes stop immediately, but they never respond by running around the barrier.
正确答案是B，不是C，”if the beetle can change directions WHILE RUNNING, then the "temporary blindness" hypothesis must be incorrect. (if the beetle were temporarily blind, it wouldn't know which direction to change toward!)
on the other hand, this evidence seems to support the "fatigue" hypothesis, because ... this is just how fatigue works, in general. the longer a creature runs, the more breaks it needs... so, supports #1, basically undermines #2.”
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