Logical Reasoning

PT142 · S2 · Q15 Often a type of organ

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Often a type of organ or body structure is the only physically feasible means of accomplishing a given task, so it should be unsurprising if, like eyes or wings, that type of organ or body structure evolves at different times in a number of completely unrelated species.

Background

A lot of organs or body parts are the only feasible physical way to do what that thing does, so it's not shocking that lots of completely unrelated species will evolve similar organs or body parts at different times.

Setup

No matter their lineage or habitat, animals have fundamentally similar needs. So, ...

Evaluation

We need to connect these two threads. It's unsurprising that lots of different animals have evolved the same organs or body parts, since there's only one way to accomplish certain tasks and lots of animals have similar needs.

A logical completion might sound like, they have similar needs and so "they evolve similar parts", or (since successful mutations become "selected" by evolution)

Goal

Something safely worded that sounds like

15.

Which one of the following most logically completes the last sentence of the passage?

  1. will often live in the

    Not About Cohabitation

    This blank is supposed to be about sharing similar organs / body parts, not about sharing a habitat.

    1% picked this

  2. Correct

    will in many instances evolve

    Why this is right

    Yes, this loops back to connect with the first strand of the conversation, which is that very disparate animals end up with similar organs and body parts. Since there's only one way to accomplish task X, if lots of different animals need X, then evolution will favor mutations that allow the animal to accomplish X (and those adaptations will look very similar since there's only one way to get there)

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

    75% picked this

  3. will develop adaptations allowing them

    Missing "Common" Part

    This doesn't do as good a job of connecting back to the first sentence, since it doesn't emphasize that these adaptations will be strikingly similar to those of very different animals.

    22% picked this

  4. will resemble other species having

    Opposite: "different needs"

    The thrust here is that "same needs" leads to "similar organs / body parts (resemblance)". This is talking about the similarity coming from different needs.

    2% picked this

  5. will all develop eyes or

    Too Strong: "all"

    Whenever LSAT authors name an example or two, in an offhand "such as X or Y" kind of way, those examples are not in any way crucial to the argument or the answer. It's more common than not that LSAT uses these examples to create a trap answer that is overvaluing the importance they played in the author's conversation. The author was never saying that animals will all develop eyes or wings. Those were just two examples of similar organs / body parts that are shared by many different types of animals.

    0% picked this

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