Reading Comprehension

PT127 · S4 · P2 · Q8 Inclusive Fitness Theory

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Mechanisms for recognizing kin are found throughout the plant and animal kingdoms, regardless of an organism's social or mental complexity.

Topic

Why kin recognition exists among animals and how it can be explained by different evolutionary theories.

Framework

Answer / Explain

Main Point

Scientists have several explanations for why animals recognize their kin: inclusive fitness theory proposes it’s to protect their own genetic legacy by helping relatives, but in some cases (like with tiger salamanders), avoiding kin may purely be for self-preservation to reduce risk of disease. *The Most Valuable Sentence is probably the last sentence of P2: and the last sentence of P3: *

P1: Introduction to Inclusive Fitness Theory

All kinds of organisms can recognize their kin, and one important theory (inclusive fitness) says this happens so creatures can increase the survival of their own genes—not just through offspring, but through relatives, too. This theory helps explain behaviors that don’t seem to benefit an individual directly, like sterile worker bees helping their family.

P2: Applying Inclusive Fitness Theory to Cannibalism

This theory is supported by studies of cannibal tadpoles: they usually avoid eating their relatives, which makes sense if they’re trying to protect their own genetic legacy. Occasionally, ultra-hungry tadpoles will eat siblings anyway—implying that self-preservation can sometimes override this behavior.

P3: Alternative Explanation—Disease Avoidance

But inclusive fitness isn’t the only answer! For tiger salamander cannibals, avoiding kin may actually just be about not catching deadly diseases, since they’re more likely to get sick from eating relatives. For them, kin recognition may not be about helping family, just avoiding illness and preserving their own life.

8.

Which one of the following most accurately expresses the main point of the passage?

  1. Correct

    Some findings support the hypothesis

    Why this is right

    Paragraph 2 gives us the findings that support the inclusive fitness explanation for kin recognition (helping relatives "increases your own total genetic representation"), whereas inclusive fitness does not explain all instances of kin recognition. Paragraph 3 talks about a case (tiger salamanders) where kin recognition is not being done in order to help relatives, but rather to help oneself survive. This answer is being cheeky by avoiding using the term inclusive fitness theory, but it has our central topic, Kin recognition, and it's providing the passage's answers to the central purpose of, "Why does kin recognition occur? How did it emerge evolutionarily?"

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

    78% picked this

  2. Current research supports the view

    Unsupported Comparison: as various

    This answer is saying that the number of ways that species have to recognize kin matches the number of reasons that species have to want to recognize kin. What a weird sentiment! The main point of the passage was definitely not a cool mathematical observation: "Check it out everyone --- there are 13 different reasons why species would want to recognize kin, and there are 13 different mechanisms that species can use to recognize kin." Within this passage we learned of two general purposes served by kin recognition, "protecting relatives vs. protecting oneself", and we learned of one mechanism for kin recognition, "nipping at other tadpoles". We have no idea how tiger salamanders recognize kin. We only talked about why they do.

    14% picked this

  3. Recent research involving tiger salamanders

    Wrong Emphasis Opposite: undermines

    We don't need to keep reading beyond the first five words. There's no way the central topic of the passage was "recent research involving tiger salamanders", so that should not be the Naming Part of our main point answer. Tiger salamanders were brought in as a qualifying subsidiary point at the end. "Yes, inclusive fitness offers a partial answer to why kin recognition develops, but there are other reasons why kin recognition develops. For example, tiger salamanders." Also, because the tiger salamander example showed how kin recognition benefited the individual, it was supporting, not undermining traditional evolutionary theory.

    2% picked this

  4. New research involving tiger salamanders

    Wrong Emphasis

    Again, it would seem very weird to start a main point sentence with "tiger salamanders", when they were just a subsidiary part of the passage. The main event is "kin recognition", which this answer doesn't even mention once. This answer makes it sound like the passage was a Challenge Position passage, trying to debunk a group of theorists who argued that the traditional theory of natural selection is not strongly supported by evidence, given the case of the spadefoot toad tadpoles.

    1% picked this

  5. While traditional evolutionary theory was

    Strong / Contradicted: fully explained

    The author says at the end of the 2nd paragraph that inclusive fitness "offers at least a partial answer", and then at the beginning of the 3rd paragraph says, "but there may be other reasons why organisms recognize kin". So the author explicitly suggests that inclusive fitness theory does not fully explain kin recognition.

    5% picked this

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