#1 - In the bodies of reptiles, some industrial by-products

[c-erv]

Hello,

For this question I was able to narrow my answer choices down to B and C as both introducing alternatives for the flawed conclusion. However I had a hard time distinguishing between the two answers. Is C wrong because the food the alligators ate would still constitute as entering the swamp's ecosystem?

Thank you

[Claire Horan]

Yes, you are correct. If the alligators ate something containing industrial by-products, that would count as the by-products having entered the alligators' ecosystem. (C), then, is an example of a possibility that fits within the argument.

[deck1134]

Is answer A out of scope?

[Adam Tyson]

I'm no fan of "out of scope" as an explanation for an answer choice being wrong, deck, because it covers such a broad swath of concepts that it ultimately is, usually, not very useful or informative. Too often I see students saying an answer is "out of scope" as a shortcut for "I don't get it but I'm pretty sure it's wrong", or for "the argument wasn't talking about that" (which is NOT always a good reason to reject an answer, because new information is an important element of a lot of correct answers on the LSAT).

So, what is really wrong with answer A? It's a Flaw in the Reasoning question, and answer A doesn't describe a flaw! It's talking about the right ideas - developmental abnormalities and elevated hormonal activity - but did the argument need to explain any abnormalities that are not the result of elevated hormones in order to be valid? While such an explanation might be interesting and even helpful, it wasn't essential to the argument, so leaving it out isn't a problem.

Lots of wrong answers to Flaw questions bring up the argument's failure to consider something or to explain something, but if the thing not explained or considered isn't an important aspect of the argument, then leaving it out isn't a flaw!

[graceli17]

Hi, for this question, just want to make sure I have my reasoning right here.

As a family #1 Flaw question, what is given in the stimulus is taken as true. In the first sentence, there is a cause + effect statement that some industrial by products cause elevated hormonal activity. This assumes that the author does not believe anything else can cause elevated hormonal activity. Does the flaw in cause and effect exist here because of the word "some"?

[James Finch]

Hi Grace,

The issue with the stimulus here is that we are told that some industrial by-products are a cause of elevated hormonal activities in reptiles, but we don't know if that is the only cause. There is no evidence presented that would indicate this; in fact, we can compare the first sentence to the second sentence, which tells us that elevated hormonal activities is a necessary condition for certain abnormalities in reptiles. Without any evidence, we can't presume one cause is the only cause that exists, just because it is the only one mentioned. As there is no evidence presented showing the by-products to be the sole cause of the elevated hormonal activities that we know must exist, as they are required for the abnormalities that we know exist to be present. So the flaw in this causal argument is the presumption, without evidence, that the stated cause is the sole cause.

Let me know if this clears things up.

[altheaD]

I'm having a difficult time understanding this thread. Here is how I drew the diagram:
byproducts--> raised hormonal activity (reptiles) --> developmental abnormalities (alligators)

So A is attacking the second premise above, whereas B is attacking the first. Can it be stated that the source of the chain should be attacked as a rule for these flaw questions?

Also I marked D. Because "bodies of reptiles" likely applies to other reptiles besides alligators alone, and if byproducts entered the ecosystem presumably there are other reptiles in the area, it would be important to determine that it's not some freak phenomenon occuring specific to alligators...

I see how B is correct, but so are others, and I still don't understand why A is not correct, in spite of your explanations thus far.

Thanks for any further clarification help!

[Robert Carroll]

althea,

There are two different relations here, one causal, one conditional:

"Industrial by-products cause elevated hormones."

"If reptiles have abnormal development, there must be elevated hormones."

Answer choice (A) does not identify a flaw because the stimulus already told me in a premise that abnormal development requires elevated hormones. It is not possible for such development to exist without the elevated hormones, so of course it didn't explain other causes. One might object that the elevated hormones, though a necessary condition for abnormalities, might not be causing the abnormalities. That still doesn't identify a flaw - if the stimulus statement of a conditional relationship between abnormalities and hormones was not intended to identify a corresponding causal relationship, then the stimulus is already compatible with alternative causes. If so, it's not flawed in the way answer choice (A) states.

Your approach to answer choice (D) sounds like a good approach to an Evaluate the Argument question. It would be helpful to see whether these abnormalities were limited to alligators - if they affected all reptiles, or failed to affect other reptiles, we'd have information helpful to judge the conclusion better. However, it's not a flaw to fail to provide this information. The author's argument depends on there being no other causes - that's the flaw. That there are no other effects (effects on other reptiles) is not something the author is trying to argue, so the author makes no flaw in this area.

Robert Carroll