Reading ComprehensionDifficulty: Medium

PT127 S4 P2 Q11 Explanation

Inclusive Fitness Theory

A free, expert breakdown of this official LSAT Reading Comprehension question.

TopicsLocal PurposeScience

Keep going in LSAT Lab

  • Save & drill this skill — build targeted practice sets from questions like this one

  • Video walkthroughs — watch every question solved step by step

  • 81 official LSATs — as questions, timed sections & full-length tests

Start practicing free

Free to start

Full official LSAT questions are available through LawHub. This page provides LSAT Lab's explanation, strategy, and review tools without republishing the full official question.

Passage

Mechanisms for recognizing kin are found throughout the plant and animal kingdoms, regardless of an organism's social or mental complexity. Improvements in the general understanding of these mechanisms have turned some biologists' attention to the question of why kin recognition occurs at all. One response to this question is offered by the the honeybee, most of whose members do not produce offspring and exist only to nurture relatives.

Inclusive fitness theory has also been applied usefully to new findings concerning cannibalism within animal species. Based on the theory, cannibals should have evolved to avoid eating their own kin because of the obvious genetic costs of such a practice. Spadefoot toad tadpoles provide an illustration. Biologists have found that all tadpoles when it becomes very hungry, apparently putting its own unique genetic makeup ahead of its siblings'.

But there may be other reasons why organisms recognize kin. For example, it has recently been found that tiger salamander larvae, also either omnivorous or cannibalistic, are plagued in nature by a deadly bacterium. Furthermore, it was determined that cannibal larvae are especially likely to be infected by eating diseased species members. which an organism preserves its own life, not as a means to aid in relatives' survival.

What this question is testing

Local Purpose

Your task

Identify why the author included the referenced detail at that point in the passage — its function, not its content.

Common trap

Answers that merely repeat or summarize the topic of the detail instead of describing the role it plays.

Winning move

Ask what job the detail does for the paragraph, then for the passage's broader point.

Reading along? Open the full official question in LawHub — we show a fragment here and keep the reasoning in our own words.

The question
11.

Which one of the following most accurately describes the function of the last sentence of

Answer choices

  1. Correct74% picked this

    to draw attention to behavior that further complicates the set of facts to be explained by any theory of natural selection

    Why this is right

    Gross. This is definitely not language most of us would predict, but it resonates with the idea that the final sentence of the 2nd paragraph is an exception to the general trend described in the rest of that paragraph. For the most part, the case of the cannibal tadpoles aligns with the inclusive fitness theory of "thou shalt protect thy relatives". But the final sentence shows that this is a general rule of thumb, not an absolute. This answer choice is reinforced by the 2nd to last sentence of the 2nd paragraph. And in general, when we're asked about the purpose / function of a detail, the correct answer most commonly reinforces the language of the preceding sentence. The preceding sentence is saying that "inclusive fitness theory offers at least a partial answer to why kin recognition develops". This answer is basically saying that an adequate theory of kin recognition will need to account for the exceptional cases in which an individual puts its own survival ahead of that of its kin.

    Skill tested: Local Purpose · how this choice captures the passage's function is the move to repeat next time.

  2. Out of Scope: most species1% picked this

    to explain why cannibals in most species eat their kin less often than do cannibal

    We have no idea what is true or false about cannibals in most species. The passage only discusses cannibalism within this one species of tadpoles.

  3. Opposite18% picked this

    to describe behavior that lends support to the account of kin recognition presented in

    This behavior in the final sentence is an exception to the account of kin recognition presented in the 2nd paragraph. It's not lending support; it's adding a caveat / a qualification.

  4. Too Strong: unexplainable2% picked this

    to offer evidence that the behavior of cannibal spadefoot toad tadpoles

    The author is never supporting the desperate claim that spadefoot tadpole behavior is unexplainable. In fact, that final sentence surmises a potential explanation when it says, "apparently, (in choosing to eat their kin rather than starve), the cannibal is putting its own unique genetic makeup ahead of its siblings'."

  5. Opposite5% picked this

    to imply that the described behavior is more relevant to the issue at hand than is

    The thrust of the 2nd paragraph is that cannibal tadpoles avoid eating their kin. That's why the author is even talking about them. This last sentence is just acknowledging an exception, a complication, a caveat. It's not trying to put THIS behavior center-stage.

Continue the review in LSAT Lab

Save this question, watch the video walkthrough, and drill similar questions in your LSAT Lab account.

Save and practice this skill
LSAT Lab

Turn this review into a targeted study plan.

Save this question, drill more like it, watch the video walkthrough, and track your progress in your LSAT Lab account.

Start practicing free