Delta green ground beetles sometimes remain motionless for hours at a

Question

Delta green ground beetles sometimes remain motionless for hours at a stretch, although they are more active in wet years than in dry years. In 1989 an observer spotted ten delta green ground beetles in nine hours; in 1985 the same observer at the same location had counted 38 in about two hours. This difference probably does not reflect a drop in the population of these rare beetles over this period, however, because 1985 was a wet year and 1989 was relatively dry.

Which one of the following, if true, most strongly supports the conclusion drawn above?

(A) Because of their excellent camouflage, delta green ground beetles are almost impossible to see if they are not moving.

(B) The only habitat of delta green ground beetles is around pools formed by the collection of winter rains in low-lying areas.

(C) Della green ground beetles move about very little to get food; most of their moving from one place to another is related to their reproductive behavior.

(D) Della green ground beetles are so rare that, although the first specimen was found in 1878, a second was not found until 1974.

(E) No predator relies on the delta green ground beetle for a major portion of its food supply.

daagh · Answer

In 1985, 38 beetles were spotted. In1989, only 10 were spotted. The drop could have been due to the poor physical visibility caused by the clever dodging due to the excellent camouflage of the beetles rather than due to a trending lower population. A strengthens the argument.

Snezanelle · Answer

I don't get why E is incorrect. What if a predator has just eaten a few beetles and an observer saw the decreased number of the beetles right after that?

Prithvi08 · Answer

I get why A is right but doesn't option E even out the play field for both the situations? It states that yes the drop wasn't cause of any predation. Hence ruling out a possible cause behind the drop and strengthening the fact that weather might be a possible reason?

SathyaSree · Answer

A mentions that there are other factors responsible for drop in counts of beetles. Which means that this weakens the argument. Ideal strengthen answer should add info to specify that there are no other factors right I.e wet and dry area is only reason to see reduced number of beetles ?

mggmat19 · Answer

This argument completely relies on the fact that beetles die because of getting eaten by predators. There can be other factors such as environment, availability of food etc that can play a significant role in life cycle of the beetles. Therefore this option is not a preferred choice.

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Vaishali2004 · Answer

Why is Option B wrong? Option B is supporting the argument that Delta green grows in wet environment

someshd · Answer

Option A does not account for drop in count it instead confirms that, it is not the drop in the number of della green beetles that made fewer beetles visible (10 beetles) but the fact that the beetles camouflaged themselves led to seeing fewer beetles. the beetles are still there and probably the same number of beetles are still alive and very much there.

unraveled · Answer

The stem asks for  most strongly  supporting option. Hence a comparison among the option is indeed required.
For this identify the conclusion, i assume you already did. Thus, what might be reason for the author to claim that DGGB population wasn't affected when from 38 DGGBs were seen that reduced to 10 DGGBs.

So, leave any option that does not helps us strengthen the claim. There can be more options that strengthen but the best one we need to chose.

Delta green ground beetles sometimes remain motionless for hours at a stretch, although they are more active in wet years than in dry years. In 1989 an observer spotted ten delta green ground beetles in nine hours; in 1985 the same observer at the same location had counted 38 in about two hours.  This difference probably does not reflect a drop in the population of these rare beetles over this period , however, because 1985 was a wet year and 1989 was relatively dry.

Which one of the following, if true, most strongly supports the conclusion drawn above?

(A) Because of their excellent camouflage, delta green ground beetles are almost impossible to see if they are not moving. - CORRECT. The disguise helps DGGBs remain unnoticed. Although there can be outcomes on negative side, of course with assumptions, at first instance it is strengthening the case.

(B) The only habitat of delta green ground beetles is around pools formed by the collection of winter rains in low-lying areas. - WRONG. Rains in winters can be there in dry years or wet years. Nothing as such is mentioned in the passage and thus it requires a lot more assumption/s to be made which is what best left not to be made.

(C) Della green ground beetles move about very little to get food; most of their moving from one place to another is related to their reproductive behavior. - WRONG. This is a disguise in the option. For me this is 2nd best choice since it revolves around reproduction which makes it enticing choice. But does that behaviour means population was not affected? Did the observer noticed 38 of them while they were reproducing? If yes, is there a benchmark number when we can say DGGBs were mating? All such questions make this choice weak relatively to A. Otherwise it is good.

(D) Della green ground beetles are so rare that, although the first specimen was found in 1878, a second was not found until 1974. - WRONG. Rather weakens somewhat.

(E) No predator relies on the delta green ground beetle for a major portion of its food supply. - WRONG. Irrelevant.

Answer A.

siddhantvarma · Answer

The passage doesn't say that Delta green  grow s in a wet environment. It merely states that they are  more active  in wet environments than dry environments.

Delta green ground beetles sometimes remain motionless for hours at a

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Delta green ground beetles sometimes remain motionless for hours at a

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