In 1977, a young wolf was observed entering a cave in

Question

In 1977, a young wolf was observed entering a cave in pursuit of prey. Soon, other wolves started entering the cave, and over the next few seasons, this behavior became the norm for the entire wolf pack. Before 1977, no wolf had been seen entering or leaving the cave, and no signs of wolves were found in the cave. By 2004, the entire pack was spending most of its winters in or near the cave. Therefore, these wolves are capable of adopting and passing on new behaviors, and are not merely bound by their genetics.

The argument above is based on which of the following assumptions?

A) Genetic mutations in wolves can occur in a fairly short timespan such as a few decades. 
B) New behaviors that emerge in wolf populations over the course of a couple of decades are not necessarily genetically predetermined. 
C) Only after certain patterns of behavior become the norm for a given animal population can it be inferred that a genetic mutation has occurred in that group. 
D) The social actions of wolves are fully independent of their genetics. 
E) The wolves' new pattern of behavior will continue for several generations to come.

BalaGmat · Answer

I don't understand why B? please explain.

Marcab · Answer

A negation technique can be made handy here.
Whats the conclusion:  these wolves are capable of adopting and passing on new behaviors, and are not merely bound by their genetics.

Only B is even close to the stimulus. On negating this answer choice we get: "New behaviors that emerge in wolf populations over the course of a couple of
decades are  not  necessarily genetically predetermined", implying that the new behaviours are predetermined. If these are predetermined then how one can conclude that these wolves are capable of adapting and passing on new behaviors.

Negated B destroys the conclusion and hence B is the answer.

Archit143 · Answer

Lets focus on the conclusion ;- wolves are capable of adopting changes and are not merely bound by genetics.

We have to find an answer that was considered while framing the argument i.e to say Assumption.
I ended up selecting B as it kills the conclusion when negated.
 But yes it was not easy to eliminate C and E...Here is why i eliminated 
C:- It is a generalized answer just as inference type answer..we are required to find assumption not the conclusion. Hence C is out.
E:- It is what follows from the statement in a nutshell Must be true type answer... But yes even in Must be true this wont have been a correct answer as it strays out of the scope.. We cannot comment when will their this adopted behavior end. It may take generations or may end very soon.
D:- Is not true and cannot be considered an assumption. we are not concerned about just one habit of the wolves. It is contrary to barking of dogs if one dog barks all of them will bark, hence its a social action and is genetic.

I think in assumption questions we should without wasting time eliminate on the basis of out of scope and other, zero it down to two and then use negation technique.

am85 · Answer

That was a great explanation.

Furthermore, i would like to draw the following in order to help visually in order to find the gap in logic.

behavior became the norm for entire W.P. ----------------------------------------------------> Capable passing new behav & not merely bound genetics

What we should assume in order to fill the gap bridge and make more solid the whole arguments? Probably that genetics is not the only factor in order to determine wolves behaviours.

Answer B states a very clear idea that genes are not necerssarily the only factor.

Abhishek009 · Answer

In 1977 after observing a wolf entering the cave other wolves too started following it and it was observed after 27 that the entire the entire wolf pack spending the winters near the caves for a couple of years. 
 
 This concludes that the wolves can adopt new behaviour and are not bound by genetics.

Answer will be (B)
 
We are simply presented with a data of 27 years within which the entire wolf population starts adopting the particular survival strategy (during winters).

Had it been a genetic adaptation , the wolves would have resorted to such practices earlier, but unfortunately that was not observed prior to 1977.

Lets try to negate option (B)
 
" New behaviors that emerge in wolf populations over the course of a couple of decades are necessarily genetically predetermined. "

If the behaviours are predetermined then the arguement directly attacks the conclusion.

Hence answer will be (B)

aj33 · Answer

Hello,

only answers B and D are relevant. If we consider answer D and negate it then we see that it says not fully. In assumption it is of the most importance that the answer is binary 0 or 1. Therefore the answer to D is not binary. Hence we remove option D.

VerbalBot · Answer

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In 1977, a young wolf was observed entering a cave in

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