#18 - Some killer whales eat fish exclusively, but others

[KelseyWoods]

Hi omccord!

The question stem is asking us to support the biologists' hypothesis so our first step is to identify their hypothesis.

Hypothesis: young harbor seals start with an aversion to all killer whales but then learn to ignore those that do not eat seals

Now let's look at the premises that led the biologists to that hypothesis.

Premise: dialects of seal-eating killer whales are recognizably different from those of killer whales that do not eat seals
Premise: harbor seals use their ability to distinguish between different killer-whale dialects to avoid seal-eating killer whales

So we know that harbor seals can distinguish between the dialects of the seal-eating killer whales and the non-seal-eating killer whales and that they are able to avoid the seal-eating killer whales. The hypothesis is that young harbor seals start our by avoiding all killer whales, but then they learn that they do not need to avoid the non-seal-eating killer whales.

Causal reasoning occurs whenever you have one thing actively making another thing happen. In this case, the biologists observed that harbor seals ignore the non-seal-eating killer whales and have hypothesized that the thing that makes the seals ignore the non-seal-eating killer whales is that they learn that whales with a specific dialect don't eat seals. We're trying to strengthen this explanation--we're trying to support the idea that seals start out avoiding all killer whales, but then they learn that whales with certain dialects are not a threat and so they no longer avoid those whales.

Answer choice (C) strengthens this argument by telling us that when seals hear a killer whale dialect they have never heard before, they swim away. This supports the idea that seals start out avoiding all killer whales, and the reason that they stop avoiding the non-seal-eating killer whales is that they learn that these whales with those dialects do not pose a threat to them. Their default is to fear all killer whales so any new dialect will send them running, until they learn that the whales with this new dialect are not a threat.

Answer choice (A) tells us nothing about the biologists hypothesis because it has nothing to do with why seals have an aversion to some whales but not others.

Answer choice (B) also tells us nothing about the hypothesis which only has to do with seals and not fish.

Answer choice (D) is irrelevant to the hypothesis which is just about seals and their reactions to killer whales, not other seal predators.

Answer choice (E) says that a seal can learn to distrust a type of whale through experience, but the hypothesis is about instinctually distrusting all whales and then learning to trust a specific type of whale through experience.

Hope this helps!

Best,
Kelsey

[mkarimi73]

I interpreted (D) as saying: "Young harbor seals show no natural aversion to any seal predators other than killer whales," meaning that they show such an aversion to killer whales only. Thus, one could argue that this strengthens the hypothesis by making it more likely that young harbor seals show no natural aversion to anyone else except the killer whales, and that this would make it more likely that young harbor seals start off with this aversion at an early age. (The stimulus also states that harbor seals are able to distinguish between dialects to avoid seal-eating killer whales. And then the stimulus arrives at a conclusion about young harbor seals. So, I was looking for an answer choice that spoke to this development of distinction.)

But that wasn't what (D) said. According to you guys, (D) only speaks to "other predators," which would make this answer out-of-scope, especially since the hypothesis concerns killer whales.

I was thrown off by "mature" harbor seals in (C), thinking that this answer choice was out-of-scope in my original analysis, since the hypothesis concerned young harbor seals. In the end, it seems that they were looking for that nonsense "no cause, no effect" relationship, but they could have easily written a much better answer choice for (C) in order to test that concept for future, aspiring attorneys.

So, what do I do here? Try to figure out what they mean by "other" in (D), or try to figure out what they mean by "mature"? I would argue "mature" could mean a variety of things.

[Adam Tyson]

Answer C supports the idea that seals start out life with a general aversion to all killer whales and only get comfy with some whales after becoming familiar with them and learning that they are safe to be around because they don't eat seals. So C isn't about any "nonsense" at all! It's further evidence that if a seal is unfamiliar with a killer whale, they stay away from it! Of course that would continue into maturity - if they never got familiar with a particular killer whale, they would ALWAYS stay away from it, throughout their lives. They will only stop behaving that way if they get familiar with it and learn that it is safe.

Imagine if the opposite were true, and mature seals showed no aversion to unfamiliar killer whales. Wouldn't that weaken the claim that they stay away from all killer whales until they learn that they are safe?

And note that the stimulus is not only about the young seals, but about all harbor seals. They hypothesis is that they start off with one type of behavior, and they only change that behavior if and when they learn new information, whenever that may occur in the course of their lives.

D is, as you said, out of scope. Their lack of aversion to other predators has no bearing on whether the hypothesis about killer whales is correct.

[fortunateking]

Dear PS people,
The stimulus doesn't contain causality indicators, so why can it be regarded as causal reasoning? Doesn't it need causal indicators to be causal reasoning? Just like you need conditional indicators to form conditional reasoning.
Also, I agree that answer choice C supports the idea that seals start out avoiding all killer whales, however, I don't see how it can support the latter part of the conclusion, that the seals stop avoiding the non-seal-eating killer whales when they learn that these whales with those dialects do not pose a threat to them. It doesn't even mention anything about learning.

[Robert Carroll]

fortunateking,

"Causal indicators" are just words and phrases that are often used when an author is trying to link two phenomena causally. They're not universal and necessary indicators that the author is attempting to link two phenomena causally. A causal connection is simply the production of one state of affairs from another. The author, or more precisely, the marine biologists, think that harbor seals start with one kind of aversion and later develop a more refined and selective aversion. Their behavior changes, and it changes as a result of some physical phenomenon. That's a causal connection.

As you say, answer choice (C) supports part of the conclusion. It's not harmful to the other part. That strengthens the conclusion! As always with Strengthen answer choices, the correct answer does not have to make the argument perfect. That's the standard for a Justify question, not Strengthen.

Robert Carroll