Reading comp PrepTest 157 · Section 4 · Question 20
Passage
Political arguments about biodiversity and the preservation of endangered species generally assume we know what a species is. Yet answering
Remaining source text redacted.
Passage walkthrough
Passage Summary Topic:
Science
Paragraph 1
Main Point:
There's a debate in how to classify bird species between "lumpers," who use the "biological species concept" to guide their decisionmaking, and "splitters" like Charles G. Sibley, who use an increasingly popular "phylogenetic approach," and this debate is likely to have political and economic implications.
Key Lines?
Paragraph 1, Sentences 4-5 (P1, S4-S5) - Def. of one side of debate ("lumpers")
P1, S6-S7 - Def. of other side of debate ("splitters")
P2, S2 - Important ex. of "splitter" (Sibley)
P3, S2 - Criticism of ex.
P4, S1 - Author's conclusion
Meta-Structure?
Describing a Debate: There's clearly a debate in this passage. On the one side, we have the until-recently dominant "lumpers," who use their biological species concept to group similar bird populations into one species. On the other side, we have the ascendant "splitters," who may include the controversial Charles G. Sibley among their ranks. They divide bird populations into separate species using the phylogenetic approach. A passage featuring a debate could either utilize a Describe a Debate or a Resolve a Debate Meta-Structure — it all depends on whether the author is passive or active in the passage. A passive author will generally describe the debate without taking a side or attempting to reconcile the two sides. An active author will argue that one side is preferable or that both sides can get along. The author spends nearly the entire passage describing both sides of this ornithological debate, which means this passage is better understood as a Describe a Debate passage. Accordingly, the main point will represent the two sides of the debate (or simply assert that there is a debate). However, there is an important wrinkle: the author's conclusion asserts that this debate "undoubtedly has political and economic stakes." This will need to be part of the main point as well.
List: This passage is also organized around a list: the two sides of the debate. This list is mostly confined to the first paragraph, although the "splitter" side gets fleshed out with the discussion of Charles G. Sibley in the second and third paragraphs. When the author organizes a passage around items on a list, it's a good idea to note or remember where each item was discussed. We're likely to get several Minor Detail questions about each side, so be prepared to refer back to your notes and passage as needed.
Examples: The author also makes good use of examples in this passage. The primary example is Charles G. Sibley, who is described in the second and third paragraphs. We also learned about a few examples of controversial reclassifications Sibley supported at the end of the second paragraph. We get an example of a criticism of Sibley's work in the third paragraph. Finally, we get an example of one of the political and economical implications of the species question at the end of the passage. When a passage has this many examples, we are bound to get a question about at least one of them. The question could be about the specific example itself or the general idea the example illustrates. So, let's list both:
First, let's note that many test-takers tend to overestimate the importance of people in passages. Such test-takers tend to think any person mentioned is likely to be the main subject. Call it the anthropocentric fallacy, if you'd like. Such test-takers will probably think Charles G. Sibley (who, in fairness, did take up a lot of real estate in this passage) is the main subject. Many wrong answer choices to the Main Point and other big-picture questions will try to entice such test-takers by emphasizing Sibley's centrality to the passage. We should start by noting that Sibley was just an example of one side of the central debate in this passage (notice how he was introduced — "The late Charles G. Sibley ... could be called a splitter" (P2, S1)). Second, this is an exceptionally detail-centric passage, defined by lists and numerous examples. Expect many minor-detail questions to follow. We'll probably have to look back at the passage more than we'd like to, but we won't have time to look back for every question, much less every answer choice in every question. If possible, try to remember the main point and memorize some basic facts about each side of the central debate. To the latter point, try to remember the following: "Lumpers" use the biological species concept, which focuses on whether populations interbreed in the wild. In contrast, "splitters" use the phylogenetic approach, which focuses on whether members of a population share a genetically traceable feature. Remembering those basic facts will help us avoid some unnecessary fact-finding missions in the passage.
Science
Paragraph 1
- Paragraph note
- Two approaches to classifying bird species: Lumpers (biological species concept) vs. splitters (phylogenetic approach)
- Views, minor Meta-Structures, and the author's attitude
- List of approaches, item 1: Lumper/Biological Species
- Group similar species together
- Interbreed in wild → single species
- Until recently dominant approach
- List of approaches, item 2: Splitter/Phylogenetic
- Divide similar species
- "Diagnosable" ancestry (distinctive, genetically traceable features) → single species
- Increasingly popular
- Author's attitude: "confusing and controversial exercise" (second sentence)
- List of approaches, item 1: Lumper/Biological Species
- Paragraph note
- of "splitter": Sibley's DNA-DNA hybridization and revisions to species classifications
- Views, minor Meta-Structures, and the author's attitude
- of Sibley's revision: North/South American vultures more similar to storks than European vultures (last sentence)
- of Sibley's revision: Loons and grebes not related (last sentence)
- Author's attitude: "controversial revolution" (first sentence)
- Paragraph note
- Criticism and defense of Sibley
- Views, minor Meta-Structures, and the author's attitude
- of criticism: Sibley making arbitrary interpretations of DNA evidence
- Sibley defense: For practical reasons must limit the number of differences we accept in the same species, even if this is "slippery"
- Paragraph note
- Author's conclusion: Political and economic implications of the species question
- Views, minor Meta-Structures, and the author's attitude
- Ex of implication: Increasing number of species increases the number of species needing protection (last sentence)
Main Point:
There's a debate in how to classify bird species between "lumpers," who use the "biological species concept" to guide their decisionmaking, and "splitters" like Charles G. Sibley, who use an increasingly popular "phylogenetic approach," and this debate is likely to have political and economic implications.
Key Lines?
Paragraph 1, Sentences 4-5 (P1, S4-S5) - Def. of one side of debate ("lumpers")
P1, S6-S7 - Def. of other side of debate ("splitters")
P2, S2 - Important ex. of "splitter" (Sibley)
P3, S2 - Criticism of ex.
P4, S1 - Author's conclusion
Meta-Structure?
Describing a Debate: There's clearly a debate in this passage. On the one side, we have the until-recently dominant "lumpers," who use their biological species concept to group similar bird populations into one species. On the other side, we have the ascendant "splitters," who may include the controversial Charles G. Sibley among their ranks. They divide bird populations into separate species using the phylogenetic approach. A passage featuring a debate could either utilize a Describe a Debate or a Resolve a Debate Meta-Structure — it all depends on whether the author is passive or active in the passage. A passive author will generally describe the debate without taking a side or attempting to reconcile the two sides. An active author will argue that one side is preferable or that both sides can get along. The author spends nearly the entire passage describing both sides of this ornithological debate, which means this passage is better understood as a Describe a Debate passage. Accordingly, the main point will represent the two sides of the debate (or simply assert that there is a debate). However, there is an important wrinkle: the author's conclusion asserts that this debate "undoubtedly has political and economic stakes." This will need to be part of the main point as well.
List: This passage is also organized around a list: the two sides of the debate. This list is mostly confined to the first paragraph, although the "splitter" side gets fleshed out with the discussion of Charles G. Sibley in the second and third paragraphs. When the author organizes a passage around items on a list, it's a good idea to note or remember where each item was discussed. We're likely to get several Minor Detail questions about each side, so be prepared to refer back to your notes and passage as needed.
Examples: The author also makes good use of examples in this passage. The primary example is Charles G. Sibley, who is described in the second and third paragraphs. We also learned about a few examples of controversial reclassifications Sibley supported at the end of the second paragraph. We get an example of a criticism of Sibley's work in the third paragraph. Finally, we get an example of one of the political and economical implications of the species question at the end of the passage. When a passage has this many examples, we are bound to get a question about at least one of them. The question could be about the specific example itself or the general idea the example illustrates. So, let's list both:
- Second and third paragraph: Charles G. Sibley, a controversial example of the "splitter" approach to species classification
- End of the second paragraph: North/South Am. vultures more closely related to storks than European vultures, an example of Sibley's controversial findings
- End of the second paragraph: Loons and grebes not related, an example of Sibley's controversial findings
- Third paragraph: Criticism of "arbitrary" nature of Sibley's approach, an example of the controversy surrounding Sibley's approach
- Fourth paragraph: Increasing number of species would increase the number of species needing protection, an example of the political/economic stakes surrounding species classification
First, let's note that many test-takers tend to overestimate the importance of people in passages. Such test-takers tend to think any person mentioned is likely to be the main subject. Call it the anthropocentric fallacy, if you'd like. Such test-takers will probably think Charles G. Sibley (who, in fairness, did take up a lot of real estate in this passage) is the main subject. Many wrong answer choices to the Main Point and other big-picture questions will try to entice such test-takers by emphasizing Sibley's centrality to the passage. We should start by noting that Sibley was just an example of one side of the central debate in this passage (notice how he was introduced — "The late Charles G. Sibley ... could be called a splitter" (P2, S1)). Second, this is an exceptionally detail-centric passage, defined by lists and numerous examples. Expect many minor-detail questions to follow. We'll probably have to look back at the passage more than we'd like to, but we won't have time to look back for every question, much less every answer choice in every question. If possible, try to remember the main point and memorize some basic facts about each side of the central debate. To the latter point, try to remember the following: "Lumpers" use the biological species concept, which focuses on whether populations interbreed in the wild. In contrast, "splitters" use the phylogenetic approach, which focuses on whether members of a population share a genetically traceable feature. Remembering those basic facts will help us avoid some unnecessary fact-finding missions in the passage.
Question prompt
The passage provides information
Remaining source text redacted.
Why the credited answer is right
Credited answer: D
The notes below walk through why it fits the stem and how to eliminate the rest.
Question Type
Science
Answer choices
-
AWhen did Charles G. Remaining source text redacted.
Why choice A is not credited
Dates tend to stick out in passages. A quick glance at the second paragraph would confirm no dates mentioned were there. So the passage does not provide the information needed to answer this question. We can eliminate this. -
BWhat are two continents Remaining source text redacted.
Why choice B is not credited
We just answered Question 19, which required us to review the reference to storks in the second paragraph. Although we learned that vultures are found in the Americas and Europe, we never were told which continents storks can be found. So the passage does not provide the information needed to answer this question. We can eliminate this. -
CWhat common traits led Remaining source text redacted.
Why choice C is not credited
We just answered Question 19, which required us to review the reference to the commonly held belief that loons and grebes are related. But in our review, we never learned why loons and grebes are thought to be related. So the passage does not provide the information needed to answer this question. We can eliminate this. -
DWhat is one objection Remaining source text redacted.
Why choice D matches the stem
Question Type:
Minor Point/Must Be True
Strategy Overview:
Remind ourselves of the main point of the passage, then head to the answers, focusing on those that line up with the main point and then using our notes/the passage to find the correct answer
Answer Anticipation:
This question stem provides no indication as to the topic of the correct answer or where it'll show up in the passage. As such, we'll need to rely on our big-picture understanding of the passage to answer this question. We should start by reminding ourselves of the main point (either by reviewing what we said after reading the passage or by rereading our answer to the main point question). From there, we can head to the answers, deferring on those that don't line up with the main point. For those that do, we'll use our notes and the passage to see if it's correct.
Answer Choice Explanation:
The existence of at least "one objection" to Sibley's work is certainly consistent with the main point of this passage. If there's a debate between "lumpers" and "splitters" like Sibley, then there will be a few objections among the parties. Reviewing our notes, if necessary, we can see the beginning of the third paragraph describes one objection to Sibley's approach — that it's "arbitrary" (P3, S2). So the passage provides enough information to answer this question, making this the correct answer.
Key Takeaway:
We expected the passage's numerous examples to be tested in these questions, and this was the second consecutive question about one of those examples. -
EWhat is one non-avian Remaining source text redacted.
Why choice E is not credited
Do you recall reading anything about non-avian (non-bird) species? Probably not. Assuming they hadn't already selected (D) and moved on, an expedient test-taker would defer on this choice and look for support for (D) (which is consistent with the main point) in the passage. And any search for references to non-avain species would be in vain, as no such references were made in this passage.
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