Tiger beetles are such fast ....gmatprep ques.

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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?

A. 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.

B. 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.

C. 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.

D. If, when a beetle pauses, it has not gained on the insect it is pursuing, the beetle generally ends its pursuit.

E. 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.

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Please help me pick between B and C

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by nisagl750 » Mon Dec 24, 2012 3:37 am
dentobizz wrote: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?

A. 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.

B. 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.

C. 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.

D. If, when a beetle pauses, it has not gained on the insect it is pursuing, the beetle generally ends its pursuit.

E. 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.

Source-Gmatprep


Please help me pick between B and C

thanks
IMO B

If the beetles respond immediately to the change in insect's direction, Beetles are able to process the resulting rapidly changing visual information and does not go blind and stop. [spoiler](One hypothesis is undermined)[/spoiler]
"pause equally frequently whether the chase is up or down an incline" suggests that they cannot maintain their pace and must pause for a moment's rest Other hypothesis is supported

What is the OA?

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experts plz comment

by dentobizz » Mon Dec 24, 2012 4:07 pm
nisagl750 wrote:
dentobizz wrote: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?

A. 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.

B. 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.

C. 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.

D. If, when a beetle pauses, it has not gained on the insect it is pursuing, the beetle generally ends its pursuit.

E. 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.

Source-Gmatprep


Please help me pick between B and C

thanks
IMO B

If the beetles respond immediately to the change in insect's direction, Beetles are able to process the resulting rapidly changing visual information and does not go blind and stop. [spoiler](One hypothesis is undermined)[/spoiler]
"pause equally frequently whether the chase is up or down an incline" suggests that they cannot maintain their pace and must pause for a moment's rest Other hypothesis is supported

What is the OA?
well OA is NOT B , its C.
Here is my take on this ---

the two theories are-
1---beetle cannot maintain pace and must pause for rest
2--Beetle has speed related eye sight issues hence has to stop

so we have to prove A right AND B-wrong OR A-wrong AND B-right

Wrong answers will Strengthen both / weaken both/ just (strength/weaken) ONLY ONE/ DO nothing to BOTH

one can safely eliminate A,D and E

Now for B
In pursuing a moving insect, the beetles usually respond immediately to changes in the insect's direction, ---this shows that the beetle can easily adjust to fast changing visuals clues. Hence theory number 2 is undermined
and the beetle pause equally frequently whether the chase is up or down an incline--this shows that the beetle doesn't get tried whether he has to go uphill or downhill, otherwise he would have taken more pauses or increased the duration of his pauses while climbing up as more energy is required to climb up than come down. So This undermines theory number 1 as well. Hence this option is ruled out

Now for C
The beetles maintain a fixed time interval between pauses-- This indicates that beetle is not tried, otherwise the frequency or duration of pauses would increase,this will weaken theory number 1
although when an insect that had been stationary begins to flee, the beetle increases its speed after its next pause.----there the increase in speed indicates that the beetle can process fast changing visual clues and is not tried , so this also undermines both theories, i think.

but a official answer can't be incorrect, where am I going wrong?

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by nash.8087 » Tue Dec 25, 2012 4:36 am
As per option C: 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.

My explanation would be:
Firstly, when a stationary insect begins to fly, the beetle will approach it only "after next pause"; the beetle need to assess rapid change in direction of the fly. (Pause here is for understanding the visual information.)

And, secondly, the option states that beetle increases the speed after a pause. But the stimulus says it takes a pause for maintaining the speed. However, as per option it is not "maintaining the speed", it is actually increasing the speed. (Hence pause is not for maintaining speed.)

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by lunarpower » Wed Jan 02, 2013 3:48 pm
i received a private message about this thread.

the problem with choice (b) is that it works against both hypotheses.
* the "immediate response" part works against the blindness hypothesis. (if the beetles went blind while running, they wouldn't change direction until they paised to regain their eyesight.)
* the "pausing equally often up or down an incline" part works against the moment's rest hypothesis. (it's harder to run up an incline than to run down one. so, according to the "they get tired" hypothesis, the beetle should have to stop more often if it's running up an incline.)

choice (c) is the one you want.
* the beetle reacts after it pauses, thus supporting the idea that it's blind (and so unable to react) until it pauses. (i.e., the increase in speed is not immediate; the beetle doesn't know that it's supposed to run faster until it has stopped and looked.)
* according to this information, the rest interval between pauses is fixed. note that this is true even when the beetle runs faster, as described -- an observation that undermines the "moment's rest" hypothesis. (according to the "beetle gets tired" hypothesis, the beetle should have to stop after less time if it's running faster.)
Ron has been teaching various standardized tests for 20 years.

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by dentobizz » Thu Jan 03, 2013 9:08 pm
*
the beetle reacts after it pauses, thus supporting the idea that it's blind (and so unable to react) until it pauses. (i.e., the increase in speed is not immediate; the beetle doesn't know that it's supposed to run faster until it has stopped and looked.)
I didn't analyse the significance of 'after the pause' and hence thought C undermines the blindness hypothesis. Thanks a lot for clearing that up Ron

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by lunarpower » Fri Jan 04, 2013 2:48 am
dentobizz wrote:*
the beetle reacts after it pauses, thus supporting the idea that it's blind (and so unable to react) until it pauses. (i.e., the increase in speed is not immediate; the beetle doesn't know that it's supposed to run faster until it has stopped and looked.)
I didn't analyse the significance of 'after the pause' and hence thought C undermines the blindness hypothesis. Thanks a lot for clearing that up Ron
yep -- you should make sure to read the language of the prompt and answer choices very closely.
Ron has been teaching various standardized tests for 20 years.

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by dentobizz » Sun Jan 06, 2013 9:17 am
pointed noted, thanks Ron

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by ngk4mba3236 » Thu Apr 21, 2016 10:47 am
dentobizz wrote: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?

A. 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.

B. 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.

C. 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.

D. If, when a beetle pauses, it has not gained on the insect it is pursuing, the beetle generally ends its pursuit.

E. 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.

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hi experts(@verbal),
I think, for this particular CR the oa is C.

because, option C strengthens the 1st hypothesis (re moment's rest) and weakens the 2nd (re go blind).

please let me know whether I got this analysis correct ?