Logical Reasoning

PT151 · S3 · Q17 Traditional hatcheries raise fish

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Traditional hatcheries raise fish in featureless environments and subject them to dull routines, whereas new, experimental hatcheries raise fish in visually stimulating environments with varied routines.

Conclusion

Fish raised in the new hatcheries are more likely to survive after their release than fish raised in traditional hatcheries.

Evidence

Traditional ones raise fish in featureless environments, with dull routines. New ones raise fish in visually stimulating environments, with non-dull routines. As a result, fish released from the new hatcheries are bolder than fish released from the old hatcheries, when it comes to exploring new environments and trying new food.

Evaluate / Goal

We're mainly looking at an assumption that .

17.

Which one of the following is an assumption required by the argument?

  1. It is economically feasible for

    Out of Scope: economically feasible

    Nothing in the author's argument talks about money. Nothing says that we could/should enact this plan on a wider scale. So whether it's economically feasible or not is immaterial. The author is only trying to prove that the effect of doing this greater visual stimulation / more varied routine is that the fish end up more likely to survive as a result.

    1% picked this

  2. The quality of the environments

    Too Strong: little effect

    The author might believe that the quality of environment also has a significant effect on the fish's survival rate. If we were attracted to this because it sounded like it was suggesting a possible alternate explanation for why the fish from certain hatcheries were or were not surviving, there are a couple problems: 1. We don't actually know whether there is any difference in survival rate between the two types of fish. The author is claiming that in her conclusion, but that's not an established fact. 2. This answer doesn't differentiate between the different types of fish. We would want the answer to be more like (B) The fish from the traditional hatcheries are not having their survival rate negatively impacted by being released into lower quality environments. But even still, because of #1, an answer like that would still be wrong.

    8% picked this

  3. Correct

    Some fish raised in traditional

    Why this is right

    We were looking for an assumption that said, bolder about exploring more likely new environments ? to survive after and trying new foods release This answer is definitely relating "boldness about exploring" (timid in their foraging) to "survive after release" (die). Since "some" is so weakly worded (at least one), when you negate it, it turns into a powerful NO idea. If we negate this answer, it says NO fish from old hatcheries every die because they're too timid in foraging for food. Would that be an objection to the argument? Sure! The author is saying that fish from new hatcheries are more likely to survive because they're bolder about foraging. But if zero fish from old hatcheries die because of being too timid about foraging, that badly weakens the author's argument. If the negation of an answer is an objection, then it is a Necessary Assumption.

    Skill tested: Necessary Assumption · how this choice captures the argument's function is the move to repeat next time.

    56% picked this

  4. Hatchery-raised fish that are released

    Too Strong: need

    This is tempting, because it reinforces a connection between "bolder in trying new types of food" to "higher survival rate". But it's stronger than what the author needs to assume. Also, there's a difference between being bolder about trying new types of food and eating many different types of food. Suppose that we released some old and new hatchery fish into the same water. Initially, they all eat a diet of delicious krill. Then the krill disappears. Oh, no! The bolder new-hatchery fish are more willing to try new foods, so they try some sea-maggots and decide "not too bad". Now these new-hatchery fish survive on a diet of sea-maggots. The timid old-hatchery fish are unwilling, so they die. At no point in this story was either type of fish needing to eat many different types of food to survive. They might only need to eat one type of food (at a time) to survive. However, if that food source disappears, and they're not bold enough to try switching to a new food source, that may hurt their survival. A correct version of this answer would sound more like Hatchery-raised fish that are released into the wild are less likely to die when willing to try new types of food.

    29% picked this

  5. Fish in the wild always

    Too Strong: always

    The author doesn't need to assume that 100% of all fish everywhere live in visually stimulating environments. It won't kill the author's argument if there's at least one fish in the wild living in a dull environment (maybe Larry the clownfish got washed up into a little tide pool and now spends his days stuck in a boring crater of a rock.)

    5% picked this

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