Although both cold weather and oil spills individually can cause baby

Question

Although both cold weather and oil spills individually can cause baby-dolphin deaths, it is likely that cold weather, and not oil spills, is the culprit behind the recent increase in baby-dolphin deaths along the Gulf of Mexico coast in the months of January and February this year. Data related to the months of January and February showed that dead stillborn dolphins began washing ashore along the coast shortly after bay temperatures dropped precipitously.

Which of the following, if true, would most weaken the argument above?

Which of the following, if true, would most weaken the argument above?

A. The population of sharks – a predator of dolphins – is also declining along the Gulf of Mexico Coast.

B. Very Large Crude Carriers (VLCC) that carry oil along the coast weren’t functioning at optimal levels owing to the weather conditions.

C. Gulf of Mexico coast experiences similar weather trends during January and February of every year.

D. In traditionally warm areas such as Mediterranean sea, cold weather is known to cause leaks in tankers not designed to withstand sudden temperature drops.

E. During January and February this year, moderate south to southwest winds that accompany the temperature drops moved the oil spilled by a tanker towards areas where dolphin calves breed.

ryanstarr · Answer

I want to start this one by saying jeez, Bunuel--this is a grim argument no matter which way you slice it. Should we all just forget the business-school thing and study marine biology instead? Because saving these baby dolphins feels like more of a priority right now than figuring out how to weaken this argument... Let's just pretend this argument is totally made up. You know, like arguments about "Vargonia" or "appendicitis" and other made-up things. Yeah, that feels a bit better now. On we go. The conclusion of this argument is that it is likely that cold weather, and not oil spills, is the culprit behind the recent increase in baby-dolphin deaths along the Gulf . You're looking to weaken the argument, meaning that you've got to find an answer that supports the negated conclusion: that cold weather is not necessarily the culprit (maybe something else is) and/or that oil spills are actually the culprit. (As a note, the more you get into the habit of negating the original conclusion before considering the answer choices in Weaken questions, the better these questions tend to go. If you're struggling with Weaken questions, make this part of your process by writing the negated conclusion down on your scratch paper for a while.) To the answers! A. The population of sharks – a predator of dolphins – is also declining along the Gulf of Mexico Coast. This answer lets you know that dolphins can at least check sharks off their list of worries--if the shark population is declining in the area in question, then sharks are unlikely to be responsible for the dolphin deaths. Had this answer said the opposite--that the population of sharks is increasing along the Gulf Coast--it would undercut the assertion that the cold weather is the culprit and so serve as an excellent answer. But it doesn't say that sharks have increased, and anyway, what kind of self-respecting shark would just let its food wash up on the shore? This answer is as wrong as a dead baby dolphin

. Eliminate. B. Very Large Crude Carriers (VLCC) that carry oil along the coast weren’t functioning at optimal levels owing to the weather conditions. This answer serves as evidence against the possibility that an oil spill caused the dolphin deaths, but since you'd ideally want answer that said the oil spills did cause the dolphin deaths, this answer is bunk. Later, loser. C. Gulf of Mexico coast experiences similar weather trends during January and February of every year. This is a tricky answer in that it seems to suggest that the cold weather couldn't be to blame--after all, the weather is the same every year, so something else must have changed this year, right? Alas, no: the original argument doesn't specify exactly what baseline it's using when it talks about a recent increase in the number of baby-dolphin deaths

. If the deaths in January and February represented an increase from the numbers in December, for instance, then it's entirely possible that a similar increase would have been seen as a result of the exact same weather conditions in January and February of the previous year, and in January and February of the year before that, and so on. That is, there might always be an increase in dolphin deaths due to cold weather in January and February relative to the couple of months immediately prior to January and February. Tough one, but get rid of it forever: we still haven't figured out the cause of these poor, fragile dolphins' deaths. D. In traditionally warm areas such as Mediterranean sea, cold weather is known to cause leaks in tankers not designed to withstand sudden temperature drops. This is almost a great answer, in that it suggests that cold weather can cause oil leaks, so that maybe the recent cold weather in the Gulf caused oil leaks, and maybe those oil leaks killed the baby dolphins. The problem is that there's no way to know whether this general rule about traditionally warm areas such as the Mediterranean has any bearing at all on what's happening in the Gulf. The argument never states that the Gulf is also a traditionally warm area, and as such, even if (D) is true, it may not explain what happened in the Gulf. The dolphin deaths remain a mystery, and onlookers remain deeply saddened. E. During January and February this year, moderate south to southwest winds that accompany the temperature drops moved the oil spilled by a tanker towards areas where dolphin calves breed. While there are definitely some problematic elements to this answer choice (not least the fact that dolphin calves aren't usually the ones doing the breeding--they're too busy dying

), it does the job that the other answers don't: it links the cold weather to oil danger. Therefore, while the cold weather is still implicated in the dolphin deaths, it weakens the part of the conclusion that says the cause of the deaths is not oil spills . It turns out that cold weather and oil spills might have joint responsibility for this cetacean catastrophe. Pick it and then never think about this question again. In all seriousness, this is a pretty classic example of a cause-and-effect argument, arguments that are almost always weakened by an answer that implicates a cause other than the cause the conclusion puts forth. While it happens to be a super tragic (and hopefully totally made up) circumstance, the CR patterns at play here will come up again and again as you study CR. Be on the lookout!

Maria240895chile · Answer

I'm still not clear how to choose E over D

VerbalBot · Answer

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Although both cold weather and oil spills individually can cause baby

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