#18 - In grasslands near the Namib Desert there are “fairy

[Robert Carroll]

shawnhaq,

The idea that termites are burrowing to hide from predators is just not in answer choice (E). We can't add that information to the answer - there is no common sense reason why that would be true, so it's pure speculation.

The only thing answer choice (E) does is show that, often, species that feed on sand termites are found near fairy circles. I could use that to say something like "Maybe sand termites live near fairy circles, if the species that feed on them are often found there." The problem with that is...it doesn't tell us anything we don't already know - the stimulus already says that sand termite colonies were found in every fairy circle they investigated. So establishing that there is a good chance sand termites live near fairy circles is just giving us a good chance of showing something the stimulus proved to a much higher degree of certainty already. Other than that, answer choice (E) does nothing - it does nothing to show that the sand termites (which we already know colonize the fairy circles) are the REASON why the circles exist in the first place.

Answer choice (A) gives evidence that fairy circles are caused by something that damages grass only at the roots. This makes the cause more likely to be something close under the surface, enhancing the case that the termites caused the circles.

Robert Carroll

[miriamson07]

Hi,

I was against answer choice A because I thought that having grass plants (albeit dying) in the fairy circle would be a contradiction of the stimulus, which states that fairy circles are entirely devoid of vegetation. In this case, I suppose we would assume that fairy circles will lose any vegetation they have by the time they become fully formed. However, because this is an assumption, and making assumptions on the LSAT is discouraged, I’d like to ask whether this assumption should be made here.

Thank you very much.

[Adam Tyson]

There's no need to make any such assumption, Miriam. Answer A talks about "newly forming" fairy circles. That means they aren't fully formed yet, so they still have some vegetation. Being devoid of vegetation would mean they are fully formed, not still in the process of forming.

[miriamson07]

Hey Adam, but how would we know that newly forming circles are not yet devoid of vegetation? What I was asking was, wouldn’t it be an assumption to think so?

[Adam Tyson]

If they are devoid of vegetation, then the circles are fully formed! A fairly circle is just a circular area in which there's no plants. That's how they defined them for us in the stimulus. So if they are still forming, there are still some plants in the circle, but they are thinning out.

[miriamson07]

If they are devoid of vegetation, then the circles are fully formed! A fairly circle is just a circular area in which there's no plants. That's how they defined them for us in the stimulus. So if they are still forming, there are still some plants in the circle, but they are thinning out.

Hi Adam,

Thank you for your response. I've been grappling with this question for quite awhile now... would it just be common sense to figure that fairy circles must have started out with plants? In hindsight, I can see how this would be so. But when I first read the stimulus, it didn't occur to me that this must be the case. I can tell from the last sentence of the stimulus that fairy circles come from something else (since they were "formed"). But I didn't necessarily think that their earlier form would be with vegetation.

Thanks!

[Adam Tyson]

Common sense, yes, but also use of context clues. The fairy circles exist in grasslands. The hypothesis is about the circles forming, which means at some point they were not there. I see two possibilities:

1. There was no vegetation at all, and then grass began to grow all over the area, but it never grew in these circular areas. Thus, the circles formed by grass growing around them but not in them.

2. The whole area was grassland, and then grass began to die in circular patches, causing the fairy circles to form.

You don't have to assume it's number 2. But answer A, if true, is telling you that it is that explanation and not the first one. And if that's true, that supports the conclusion.