Ecologist: One theory attributes the ability of sea butterflies

Question

Ecologist: One theory attributes the ability of sea butterflies to avoid predation to their appearance, while another attributes this ability to various chemical compounds they produce. Recently we added each of the compounds to food pellets, one compound per pellet. Predators ate the pellets no matter which one of the compounds was present. Thus the compounds the sea butterflies produce are not responsible for their ability to avoid predation.

The reasoning in the ecologist’s argument is flawed in that the argument

The reasoning in the ecologist’s argument is flawed in that the argument

(A) presumes, without providing justification, that the two theories are incompatible with each other

(B) draws a conclusion about a cause on the basis of nothing more than a statistical correlation

(C) treats a condition sufficient for sea butterflies’ ability to avoid predators as a condition required for this ability

(D) infers, from the claim that no individual member of a set has a certain effect, that the set as a whole does not have that effect

(E) draws a conclusion that merely restates material present in one or more of its premises

Source: LSAT

warriorguy · Answer

Option D -

the compounds together would have had a strong effect than considered individually. D points out that flaw.

Would like to know a strong reason to eliminate B? As per the stem, the author has not given any statistical correlation. So B is not very accurate; however, it draws our attention to the cause <--> effect funda.

techiesam · Answer

I think B is not right because of the word  statistical correlation .It does not states anything about a correlation.It only provides a general example or experiment with the predators.And I don't think B presents a strong cause either.Its bounded in the statistics statement.In fact I think C is more tempting than B.But  choice C  is eliminated because its out of the scope.

Chef · Answer

Can someone explain how D is the answer?

There is some compound being produced by butterflies. And, that compound is tested by putting on each pellet. What is the difference between an individual compound and combined compound?

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akshata19 · Answer

yes C is a tempting trap 
I go with D as it directly shows the flaw in the conclusion assumed by splitting the compounds and experimenting whereas C deals with the assumption part of the theory ' while another attributes this ability to various chemical compounds they produce '

Chef · Answer

Can you explain what the option C means?
Thanks!

devikeerthansr · Answer

Test was done with the individual chemical compounds.We do not know what would happen if multiple compounds were mixed together. D states the same.Hence the answer.

Ninokh · Answer

C is out of scope, as the conclusion is not based on the condition sufficient / required for predators to behave certain way.

mSKR · Answer

treats a condition sufficient  for sea butterflies’ ability to avoid predators  as a condition required  for this ability 
Treats condition sufficient as condition required

Example1: P-->Q; P maybe sufficient to result in Q .but P may not be a required condition 
Example2: Red+ Blue --> Purple; Red is a required color to make a purple but red is not sufficient

Ability to various chemical compounds maybe be sufficient but it may not be required
ability to various colors or many other factors ---> avoid predators
ability of various color is just one of many factors that can avoid predator.

But for this argument, flaw is that ecologist thinks if something is applicable for A, it may also be applicable for B. Hence D is correct; not C.

CEdward · Answer

Ecologist: One theory attributes the ability of sea butterflies to avoid predation to their appearance, while another attributes this ability to various chemical compounds they produce. Recently we added each of the compounds to food pellets, one compound per pellet. Predators ate the pellets no matter which one of the compounds was present. Thus the compounds the sea butterflies produce are not responsible for their ability to avoid predation.

The reasoning in the ecologist’s argument is flawed in that the argument

The reasoning in the ecologist’s argument is flawed in that the argument

(A) presumes,  without providing justification , that the two theories are incompatible with each other X
-justification was certainly provided

(B) draws a conclusion about a cause on the basis of nothing more than a  statistical correlation  X
-nothing about correlation exists in the passage

(C) treats a condition sufficient for sea butterflies’ ability to avoid predators as a condition required for this ability X
-the author does not treat any condition as 'required'

(D) infers, from the claim that no individual member of a set has a certain effect, that the set as a whole does not have that effect 
CORRECT. The author inferred on the basis of a select few predators, that all of the predators would not avoid the pellets.

(E) draws a conclusion that merely  restates material present  in one or more of its premises X
-the author didn't do this.

kdofe · Answer

Here the relationship seems like  Cause & Effect  but is not.  Cause & Effect  relationship is valid for "X then Y" but here the relationship is "NO Y then NO X"-- Because predators  DIDN'T  eat the compound infused pellets the compounds are  NOT  responsible to keep away the predators. The  Cause & Effect  relationship can be established & can be commented on only when the "Effect" is there, we cannot say anything about the  Cause  without the  Effect

It takes time to wrap your head around this, moreover you actually don't need to as this is a very niche problem you stumbled upon

VerbalBot · Answer

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Ecologist: One theory attributes the ability of sea butterflies

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