Read the following passage and answer the items that follow. Your answers to these items should be based on the passage only.

Passage-1
When the biological species concept is difficult to apply, some investigators use phenotype, an organism’s observable characteristics, instead. Two groups that have evolved separately are likely to display measurable differences in many of their traits, such as skull size or width of teeth. If the distribution of measurements from one group does not overlap with those of another, the two groups might reasonably be considered distinct species.

The primary purpose of the passage is to:
(a) Critique the limitations and ambiguities inherent in the biological species concept.
(b) Advocate for the universal adoption of phenotype-based species classification in all biological investigations.
(c) Describe an alternative methodology used for species differentiation when the biological species concept proves challenging to implement.
(d) Detail the specific statistical techniques used to determine if distributions of measurements from two groups overlap.

Question

Read the following passage and answer the items that follow. Your answers to these items should be based on the passage only.

Passage-1
When the biological species concept is difficult to apply, some investigators use phenotype, an organism&rsquo;s observable characteristics, instead. Two groups that have evolved separately are likely to display measurable differences in many of their traits, such as skull size or width of teeth. If the distribution of measurements from one group does not overlap with those of another, the two groups might reasonably be considered distinct species.

The primary purpose of the passage is to:
(a) Critique the limitations and ambiguities inherent in the biological species concept.
(b) Advocate for the universal adoption of phenotype-based species classification in all biological investigations.
(c) Describe an alternative methodology used for species differentiation when the biological species concept proves challenging to implement.
(d) Detail the specific statistical techniques used to determine if distributions of measurements from two groups overlap.

ONLiNE UPSC · Accepted Answer

Statement (a) is not correct. While the passage mentions that the biological species concept can be "difficult to apply" (a limitation), the primary focus is on presenting the alternative (phenotypic approach), not on a detailed critique of the biological concept itself.

Statement (b) is not correct. The passage explains the phenotypic approach as an alternative used by "some investigators" when the biological concept is difficult, not advocating for its universal adoption in all cases.

Statement (c) is correct. This statement accurately describes the passage's content. It introduces an alternative (phenotypic analysis), explains when it is used (when biological concept is difficult), and its underlying logic (separate evolution leads to phenotypic differences).

Statement (d) is not correct. The passage mentions "distribution of measurements" and non-overlap but does not detail any specific "statistical techniques" used for this determination.

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M Question 1	⏱ 0
Read the following passage and answer the items that follow. Your answers to these items should be based on the passage only. Passage-1 When the biological species concept is difficult to apply, some investigators use phenotype, an organism’s observable characteristics, instead. Two groups that have evolved separately are likely to display measurable differences in many of their traits, such as skull size or width of teeth. If the distribution of measurements from one group does not overlap with those of another, the two groups might reasonably be considered distinct species. The primary purpose of the passage is to: (a) Critique the limitations and ambiguities inherent in the biological species concept. (b) Advocate for the universal adoption of phenotype-based species classification in all biological investigations. (c) Describe an alternative methodology used for species differentiation when the biological species concept proves challenging to implement. (d) Detail the specific statistical techniques used to determine if distributions of measurements from two groups overlap.