Ravens display many sophisticated behaviors in the wild. Experiments

Question

Ravens display many sophisticated behaviors in the wild. Experiments suggest that these behaviors result partly from logical reasoning, not merely from instinct or rote learning. In one experiment, ravens were presented with food hanging on a string. To get the treat, a raven had to repeatedly reach down from its perch and pull up the string with its beak, stepping on the string after each pull to prevent slippage. Some ravens examined the situation for several minutes and then quickly performed this multistep procedure on their first try, without any preliminary trial and error. Since the ravens would not have previously encountered this situation in the wild, they could not have learned it through past experience. Hence, they apparently imagined possibilities and reasoned out what steps to take.

In operant behavioral conditioning of laboratory animals, each step in a desired behavioral sequence is typically rewarded with food. Thus, the animal can learn each step without understanding how it contributes to the overall outcome of the behavioral sequence. But no one step in the pull-up sequence—except the last—was rewarded with food; the raven had to accomplish the whole lengthy sequence in order to eat. Skeptics might object, however, that each step was mentally rewarded simply because the food came nearer, not because the raven already understood which actions would have this effect. But that explanation seems implausible. If each step were acquired by trial-and-error learning, presumably numerous trials would be required, and the entire sequence would probably take months of training.

Researchers modified the experiment to find out if ravens could have solved the puzzle by random movements that happened to be rewarding but were unsupported by logic. This time different ravens had to pull downward on the string to move the food upward. In this situation, the ravens often yanked on the string, occasionally bringing the food slightly closer. But no raven executed the full necessary sequence of motions, even though it was no more complex than in the first experiment. This suggests that the ravens found pulling downward to move food upward illogical and thus, unlike in the first experiment, could not deduce what actions were needed.

1. The main purpose of the passage is to

A. present evidence that ravens are capable of logical reasoning
B. describe various experiments designed to measure ravens’ mental ability
C. explain how ravens learn by trial and error
D. discuss the many sophisticated behaviors displayed by ravens
E. analyze the behavioral conditioning of ravens in a laboratory setting

2. In the context of the passage, the primary function of the second paragraph is to

A. assess an alternative explanation of the ravens’ behavior in the first experiment
B. discuss classic behavioral conditioning of laboratory animals
C. call into question the conclusions of the researchers who conducted the experiments with the ravens
D. argue that animals can learn each step in a behavioral sequence without understanding how it contributes to the overall outcome of the sequence
E. present the main evidence in support of the claim that ravens are capable of logical reasoning

3. According to the passage, in the first experiment some ravens

A. did not try out different procedures before successfully obtaining the food
B. were mentally rewarded for each action that brought the food closer
C. found the necessary sequence of motions illogical
D. discovered the pull-up sequence without understanding how each step contributed to the overall outcome
E. did not have to study the situation before performing the procedures successfully

4. The author of the passage would most likely conclude that a monkey, placed in a situation it had never been in before, was capable of logical reasoning if it

A. learned after only a few attempts the fastest route through a maze in order to reach an orange that was always placed at the end of the maze
B. carefully made several attempts in different ways to reach an orange displayed on a high ledge
C. had been trained to use three different tools in a complex sequence to open a locked metal box with an orange in it
D. noticed that when it pulled on a string in a certain direction an orange moved closer from the opposite direction
E. quickly unlatched several nested transparent plastic boxes on the first attempt in order to reach an orange in the innermost box

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Show Answer Question #1

Official Answer

A

Show Answer Question #2

Official Answer

A

Show Answer Question #3

Official Answer

A

Show Answer Question #4

Official Answer

E

satvikd22 · Answer

Why is E incorrect in question 3?

Sajjad1994 · Answer

(E)  contradicts the passage which clearly states that some ravens examined the situation for several minutes before performing the multistep procedure. Therefore, they did have to study the situation before successfully performing the procedures.

Jayam12 · Answer

why is option B wrong in Q1?

Doesn't the last paragraph explain an experiment that indicates that the raven's couldn't solve the puzzle?

How is option A correct? (Last paragraph doesn't present evidence that ravens are capable of logical reasoning)
Can someone help me correct my thought process?

sidpanik98 · Answer

How to differentiate between option D and E in Q4. ?

siddd30 · Answer

You need to understand the bigger picture and tone of the passage; throughout the passage the author is stating why Raven's are capable of logical decision making and ruling out alternate explanations (there is tone with words such as "explanation seems implausible", "Skeptics, might object, HOWEVER", "Ravens found pulling downward to move food upward illogical"- all these statements point to the fact that the author was not describing but that the author actually did have an opinion. While the last paragraph seems to counter the general observations, the author concludes by stating that raven's were being logical, (you need to keep in mind, using logic doesnt always translate into being optimal)- so even if their decision wasnt optimal, they were still using logic to not conduct an action.

To summarize-
1) word "describe" in second option suggests author didnt have any opinion and was just stating facts/observations - Not quite the case as we saw above
2) Doesnt provide a holistic view of the passage, since only paragraph 1 and paragraph 3 specifically describe the experiments - para 2 is ruling out an explanation for the experiment result

Let me know if this makes sense?

Cheers,

To summarize-
1) word "describe" in second option suggests author didnt have any opinion and was just stating facts/observations - Not quite the case as we saw above
2) Doesnt provide a holistic view of the passage, since only paragraph 1 and paragraph 3 specifically describe the experiments - para 2 is ruling out an explanation for the experiment result

Let me know if this makes sense?

Cheers,

parag08 · Answer

In third para author says that raven couldn't do the altered version of experiment when the steps were illogical like pulling the string could bring food upward. If same is used in the D option, this experiment doesn't help explain if the monkey is capable of logical thinking.

ParthD · Answer

Can you please explain question 2 with elimination for every option and proper explanation for the answer. Thank you!

sinhasrija7 · Answer

I did not understand why the answer is E in Q4. How this is even connecting the summary.

steynous · Answer

Hi, I understand the strong words used by the author to align A as the answer but the last/third para which in itself has been written by the author very much contradicts that ravens have logical reasoning. Infact it gives the author a neu tral stance overall taking into consideration both sides of the debate with experimental evidence.

imaityaroy · Answer

Hi 
Can someone please post official explaination.
Thanks

sayan640 · Answer

Focus on this part ... Some ravens examined the situation for several minutes and then quickly performed this multistep procedure on their first try, without any preliminary trial and error...they got in the first try...that means dint try many possibilities.

satvikd22

Why is E incorrect in question 3?

user1937 · Answer

MartyMurray  can you please explain the answer for question 4? Why is option (A) incorrect?

The passage mentions that one of the criteria for understanding if the creature behaves logically is eliminating the possibility that the creature is motivated by intermediate steps.

In option (E), the monkey would be able to know that it is nearing its target while unpacking, while in option (A), the monkey might have to traverse a path that might temporarily lead to it being a bit farther from target at certain stages.

glagad · Answer

user1937 
In Option A, the monkey "learns" after few attempts, whereas the way the passage has been written, the author is likely to believe that logical reasoning is best exhibited when the animal (in this case monkey) can breakdown the outcome of a sequence of steps by knowing that each step gets you closer to the final outcome. Monkey "learning" after a few attempts is not exhibit logical reasoning thus.

In Option E, the boxes are nested, and reaching the innermost box, takes a sequence of steps. You wrote - "the monkey would be able to know that it is nearing its target while unpacking" - but this is not what author believes, this is what the skeptics believe and author refutes.

user1937 · Answer

Thanks for the explanation.

"Skeptics might object, however, that each step was mentally rewarded simply because the food came nearer, not because the raven already understood which actions would have this effect. But that explanation seems implausible."

This is an extract from the passage. From this it seems, the author disagrees with the skeptics' view that "ravens only did so because they found nearing their goal with each try".

And the author cites the second experiment where the ravens would have succeeded as per skeptics' view, i.e. pulling downards brought food closer. But ravens didn't do so because that seemed "illogical" to them. Illogical to the ravens may not have been logical as per generic view but the fact that ravens were able to segregate actions into "logical" and "illogical" shows that ravens are capable of logical thinking.

What am I missing?

user1937 · Answer

I can give it a try.

A. assess an alternative explanation of the ravens’ behavior in the first experiment

We know from first paragraph that author kind of hints that the reason for raven's beahviour is their logical thinking. We see that in this 2nd paragraph, some skeptics questioning it saying that the ravens' actions are only due to the fact that food is nearing it. So maybe that is the alternate explanation, and maybe author is wrong. But the author also clearly refutes the skeptics' claim saying that if that were the case, the ravens would have had to take several trials.

Seems good so we can keep this option in case others do a worse job.

B. discuss classic behavioral conditioning of laboratory animals

The paragraph does discuss that animals learn through repeated trial and errors but I would not think that the author mentions the paragraph primarily to discuss this.

C. call into question the conclusions of the researchers who conducted the experiments with the ravens

The paragraph does talk about conclusions of the experiment on reasearch. In fact the passage as a whole is about that. But the 2nd paragraph is a slight deviation to attack not directly the raven's behaviour but the supporting hypothesis of the conclusion on raven's beahviour.

D. argue that animals can learn each step in a behavioral sequence without understanding how it contributes to the overall outcome of the sequence

I have marked this as option. This seems to be a tough competitor to option A. But when compared with option A, this option seems to only bring out a portion of the paragraph. It doesn't seem to incorporate the entirey of the paragraph.

E. present the main evidence in support of the claim that ravens are capable of logical reasoning

It does not provide main evidence. It only counters some skeptics' alternate reasoning.

Robo_123 · Answer

Can someone please explain the 4th question

mkeshri185 · Answer

This suggests that the ravens found pulling downward to move food upward illogical and thus, unlike in the first experiment, could not deduce what actions were needed.

this is said in the last passage last sentence. So doesn't it mean that ravens' pulling string is illogical? The author is contradicting himself then how can we directly say the main purpose of the author is to support the logical reasoning for ravens when he is admitting that ravens were not able to get success in the other experiment?

Sajjad1994 · Answer

4. The author of the passage would most likely conclude that a monkey, placed in a situation it had never been in before, was capable of logical reasoning if it

Explanation

The author argues ravens used logical reasoning because:

They solved a multistep problem on the first try without prior experience. 
 No reward until the final step so not trained step-by-step. 
 They did not solve when the situation seemed illogical (pulling down to move food up), even though mechanically similar so not just random trial and error.

We need a situation where:

Novel, monkey hasn’t encountered it before. 
 Multistep, requires several actions in sequence. 
 Solved quickly/first try, not trial and error.

A.   “After only a few attempts”  means trial and error, not first-try reasoning. So this is incorrect.

B.  Explicitly trial and error, not first-time reasoning. Incorrect

C.  Training means prior learning, not reasoning in a novel situation. Incorrect

D.  This is like the  “illogical”  scenario for ravens, they couldn’t reason it out. If the monkey just notices a single-step odd effect, that’s not multistep reasoning. Also, noticing isn’t solving a multistep problem. No

E.   This is correct.

Answer: E

Ravens display many sophisticated behaviors in the wild. Experiments

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Ravens display many sophisticated behaviors in the wild. Experiments

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