Passage-1

Researchers studying genetic control of animal behavior face challenges, as most behaviors involve multiple genes, and identifying them was difficult until recently. Even when a single gene affects behavior, definitions of a “behavioral gene” vary across disciplines. Neuroscientists, focused on the nervous system, use a broad definition, while ethologists, concerned with evolution, adopt a narrower one. Ethologists require that a behavioral gene alters a specific, normal behavior without causing illness, thus contributing to evolutionary variation. For example, the fruit fly gene Shaker causes unhealthy shaking under anesthesia and is not considered a behavioral gene by ethologists. In contrast, the gene period (per), which controls circadian rhythms, qualifies as it alters a normal, healthy behavior. Such distinctions reflect differing research priorities—neuroscience focuses on mechanisms, while ethology emphasizes evolutionary relevance—highlighting the complexity in defining and studying behavioral genetics across disciplines.

Based on the above passage, the following assumptions have been made:
1. The primary value of a gene in evolutionary terms is determined by its contribution to an organism's fitness under natural, ecologically relevant conditions.
2. A universally applicable definition of "behavioral gene" is a prerequisite for any valid interdisciplinary research in behavioral genetics.

Which of the assumptions given above is/are valid?
(a) 1 only
(b) 2 only
(c) Both 1 and 2
(d) Neither 1 nor 2

Question

Passage-1

Researchers studying genetic control of animal behavior face challenges, as most behaviors involve multiple genes, and identifying them was difficult until recently. Even when a single gene affects behavior, definitions of a &ldquo;behavioral gene&rdquo; vary across disciplines. Neuroscientists, focused on the nervous system, use a broad definition, while ethologists, concerned with evolution, adopt a narrower one. Ethologists require that a behavioral gene alters a specific, normal behavior without causing illness, thus contributing to evolutionary variation. For example, the fruit fly gene Shaker causes unhealthy shaking under anesthesia and is not considered a behavioral gene by ethologists. In contrast, the gene period (per), which controls circadian rhythms, qualifies as it alters a normal, healthy behavior. Such distinctions reflect differing research priorities&mdash;neuroscience focuses on mechanisms, while ethology emphasizes evolutionary relevance&mdash;highlighting the complexity in defining and studying behavioral genetics across disciplines.

Based on the above passage, the following assumptions have been made:
1. The primary value of a gene in evolutionary terms is determined by its contribution to an organism's fitness under natural, ecologically relevant conditions.
2. A universally applicable definition of "behavioral gene" is a prerequisite for any valid interdisciplinary research in behavioral genetics.

Which of the assumptions given above is/are valid?
(a) 1 only
(b) 2 only
(c) Both 1 and 2
(d) Neither 1 nor 2

ONLiNE UPSC · Accepted Answer

Statement 1 is correct: Ethologists' focus on "evolution" and "normal behavior" contributing to "evolutionary variation"; it implies they prioritize effects relevant to natural selection. The passage implies it by stating that &ldquo;Ethologists require that a behavioral gene alters a specific, normal behavior without causing illness, thus contributing to evolutionary variation.&rdquo; Unhealthy shaking under artificial anesthesia would likely be seen as less relevant to this natural adaptive context.

Statement 2 is not correct: The passage highlights the existence of differing definitions and their roots in disciplinary priorities, implying that research proceeds despite these differences, not that a universal definition is a strict prerequisite for all valid work.

Genetic Control of Animal Behavior

Interdisciplinary Research in Behavioral Genetics

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Passage-1 Researchers studying genetic control of animal behavior face challenges, as most behaviors involve multiple genes, and identifying them was difficult until recently. Even when a single gene affects behavior, definitions of a “behavioral gene” vary across disciplines. Neuroscientists, focused on the nervous system, use a broad definition, while ethologists, concerned with evolution, adopt a narrower one. Ethologists require that a behavioral gene alters a specific, normal behavior without causing illness, thus contributing to evolutionary variation. For example, the fruit fly gene Shaker causes unhealthy shaking under anesthesia and is not considered a behavioral gene by ethologists. In contrast, the gene period (per), which controls circadian rhythms, qualifies as it alters a normal, healthy behavior. Such distinctions reflect differing research priorities—neuroscience focuses on mechanisms, while ethology emphasizes evolutionary relevance—highlighting the complexity in defining and studying behavioral genetics across disciplines. Based on the above passage, the following assumptions have been made: 1. The primary value of a gene in evolutionary terms is determined by its contribution to an organism's fitness under natural, ecologically relevant conditions. 2. A universally applicable definition of "behavioral gene" is a prerequisite for any valid interdisciplinary research in behavioral genetics. Which of the assumptions given above is/are valid? (a) 1 only (b) 2 only (c) Both 1 and 2 (d) Neither 1 nor 2