For a species of large abalone shellfish to develop from a species of

Question

For a species of large abalone shellfish to develop from a species of smaller ones, they must spend less energy on finding food and avoiding predators, and more on competition in mating. So it is surprising that the fossil record shows that a species of large abalones developed from a smaller one only after otters, which prey on abalones, began to dominate the waters in which the abalones lived.

Which one of the following, if true, most helps to resolve the apparent discrepancy in the information above?

(A) Otters and abalones also compete for the same types of food and so are drawn to the same waters.

(B) The fossils that were studied showed the development of only one of the two species of large abalones known to exist.

(C) Otters also prey on the abalones' competitors for food and so indirectly make it easier for abalones to get food.

(D) Small abalone species tend to reproduce more rapidly than larger abalone species.

(E) Otters have a preference for large abalones over small ones and so prefer waters in which large abalones are found

Skywalker18 · Answer

For a species of large abalone shellfish to develop from a species of smaller ones, they must spend less energy on finding food and avoiding predators, and more on competition in mating. So it is surprising that the fossil record shows that a species of large abalones developed from a smaller one only after otters, which prey on abalones, began to dominate the waters in which the abalones lived.

large species developed from small species -> less energy on food/avoiding predators AND more competition in mating
Type-paradox

(A) Otters and abalones also compete for the same types of food and so are drawn to the same waters.- incorrect; this deepens the paradox

(B) The fossils that were studied showed the development of only one of the two species of large abalones known to exist.- Irrelevant

(C) Otters also prey on the abalones' competitors for food and so indirectly make it easier for abalones to get food.- Correct; It tells you that otters mean less competition for food, which would help explain why otters led to the development of a larger species of abalone from a smaller species.

(D) Small abalone species tend to reproduce more rapidly than larger abalone species.- incorrect; "More rapidly" doesn't guarantee it's fast enough to develop. The stimulus talks about small abalones developing into large ones, so their relative mating speed doesn't explain how that process happens even in the presence of a predator

(E) Otters have a preference for large abalones over small ones and so prefer waters in which large abalones are found- Out of scope; The fossil record shows that otters moved in before the development of the large abalone. Their preferences don't explain how that resulted in the small ones getting big.

Answer C

GMATNinja · Answer

Official LSAT and GMAT questions are both extremely high quality -- you can feel confident that the logic on these questions is sound.

Here, we have a discrepancy: large abalones develop from smaller ones when they spend  less  energy on finding food and avoiding predators, and  more  energy on competition from mating. Despite this, large abalones developed when a predator (otters) moved into the area.

What could resolve this discrepancy?

(C) tells us that the otters eat OTHER animals, with the result that it was easier for the abalones to get food. If its easier to get food, then  the abalones spend less energy getting food.  That's compatible with the development of large abalone.

This gives us a nice explanation for why large abalone developed when the otters arrived, and thus helps to resolve the discrepancy.

I hope that helps!

unraveled · Answer

The passage moves from food to mating to food.
How come large abalones came into existence when its habitat was full of predators?
A and B confuses things more. D is irrelevant. E is certainly good in that it lets you spend more time on it. But it gives a reason why otters are found in large abalones's water but never resolves the issue at hand.

C does this relatively well.

Answer C.

poorvi125 · Answer

I think this is a  poor quality  question and the answer's explanation doesn't justify.
The passage clearly states that for them to develop into bigger sized abalones, the need to focus  more on mating  and  less on finding food . Therefore, option C, which states that their sources of food increased, doesn't help the smaller abalones to grow into bigger sized ones.

GMATNinja

Guidance please

poorvi125 · Answer

That really helped! Thanks a lot

Posted from my mobile device

VerbalBot · Answer

Automated notice from GMAT Club VerbalBot: 

A member just gave Kudos to this thread, showing it’s still useful. I’ve bumped it to the top so more people can benefit. Feel free to add your own questions or solutions.

 This post was generated automatically.

For a species of large abalone shellfish to develop from a species of

Prep Toolkit

Top 5 GMAT Debrief Videos

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards

GMAT Critical Reasoning (CR) Questions

For a species of large abalone shellfish to develop from a species of

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards