Logical Reasoning

PT132 · S2 · Q12 Paleontologist: Plesiosauromorphs were gigantic

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Paleontologist: Plesiosauromorphs were gigantic, long-necked marine reptiles that ruled the oceans during the age of the dinosaurs.

Opposing Point

Most experts believe that plesiosauromorphs lurked and quickly ambushed their prey.

Evidence

Plesiosauromorphs were gigantic, long-necked marine reptiles that ruled the oceans during the age of the dinosaurs.

Plesiosauromorph fins were quite long and thin, like the wings of birds specialized for long-distance flight.

Conclusion

However, Plesiosauromorphs probably hunted by chasing their prey over long distances.

Evaluate

The argument assumes that the comparison between plesiosauromorph fins and the wings of birds specialized for long-distance flight applies to their function as well as their form.

12.

Which one of the following is an assumption on which the paleontologist's argument depends?

  1. Birds and reptiles share many

    Out of Scope / Weaken

    Any physical features other than fins and wings are not relevant. Furthermore, this provides an alternative explanation for the similarity between fins and wings that may not involve similar hunting patterns.

    1% picked this

  2. During the age of dinosaurs,

    Too Strong

    The argument states that plesiosauromorphs had long, thin fins, but the argument does not need to assume that they were the only marine animals that had such fins.

    1% picked this

  3. A gigantic marine animal would

    Unsupported / Too Strong

    This does not connect the premise (shape of fins) with the conclusion (hunting strategy). Furthermore, while it would prove that plesiosauromorphs hunted by chasing prey over long distances, it applies broadly to all gigantic marine animals, which the argument does not need to assume.

    9% picked this

  4. Most marine animals that chase

    Reversal

    This reverses the assumption that marine animals specialized for long-distance swimming are likely to chase their prey over long distances.

    7% picked this

  5. Correct

    The shape of a marine

    Why this is right

    This connects the common form between the fins and wings to function those fins and wings perform.

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

    82% picked this

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