Question map
Consider the following : 1. Bats 2. Bears 3. Rodents The phenomenon of hibernation can be observed in which of the above kinds of animals?
Explanation
The phenomenon of hibernation can be observed in all three kinds of animals mentioned.
Bats generally do not feed during hibernation and rely on pre-hibernation fattening and subsequent use of these reserves to fuel hibernation[1], confirming that bats do hibernate. Bear hibernation is different than most hibernating animals -[2] when a bear 'hibernates' it is really in a deep sleep with body temperature drops but not drastically and it does not wake up[2], indicating that bears exhibit a form of hibernation (though technically called torpor or winter sleep). True hibernation (like we see in ground squirrels) involves a drastic drop in body temperature but the hibernating animal will awaken occasionally to eat and defecate before resuming hibernation[3], which confirms that rodents like ground squirrels are classic hibernators.
Therefore, hibernation can be observed in bats, bears, and rodents, making option C (1, 2 and 3) the correct answer.
Sources- [1] https://www.nature.com/articles/s41598-024-52459-9
- [2] Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 11: Schedule Animals of WPA 1972 > Do you know? > p. 171
- [3] Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 11: Schedule Animals of WPA 1972 > Do you know? > p. 171
PROVENANCE & STUDY PATTERN
Full viewThis is a classic 'Science in Everyday Life' question. While standard texts (Shankar IAS) debate the technicality of 'true hibernation' vs. 'torpor' in bears, UPSC expects the broader functional definition. It rewards common sense about temperate climate survival over strict zoological taxonomy.
This question can be broken into the following sub-statements. Tap a statement sentence to jump into its detailed analysis.
- Explicitly describes pre-hibernation fattening and use of fat reserves to fuel hibernation.
- States bats generally do not feed during hibernation, indicating seasonal torpor behavior.
- Discusses torpor and energy expenditure specifically during hibernation.
- Refers to 'hibernating Indiana bats' and an optimal hibernation temperature, confirming hibernation as a behavior in bats.
- Refers to onset of hibernation and changes in body condition linked to overwinter survival.
- States 'the hibernating bats in our study area' indicating that these bats undergo hibernation.
Notes that fruit bats are important pollinators and seed dispersers, indicating that some bat species are active pollinators.
A student could combine this with the fact that many pollinators hibernate seasonally to ask whether pollinating bats (often tropical/fruit bats) follow the same seasonal dormancy patterns as other pollinators.
States a general pattern: 'pollinators come out of hibernation', establishing that hibernation is a known seasonal strategy among pollinating animals.
Use this rule plus knowing which bats act as pollinators to infer that some bat species might hibernate in climates with seasonal resource shortages.
Explains that mammals show different kinds of winter dormancy (true hibernation vs. lighter torpor/deep sleep), establishing that mammalian hibernation is variable.
Combine this pattern with the fact that bats are mammals to reason that if bats do enter dormancy, the form could vary by species and climate (torpor, true hibernation, or reduced activity).
Describes diel activity patterns in biomes, noting nocturnal animals and continuous activity in tropical rainforests.
A student could use this plus location data (tropical vs temperate ranges of bat species) to predict that tropical, continuously active ecosystems likely host non-hibernating bats, whereas temperate bats might hibernate.
Gives examples of seasonal hibernation behaviour in animals (snakes coming out of hibernation), illustrating that hibernation is a seasonal response among diverse taxa.
Extend this general seasonal-hibernation pattern to mammals and then ask whether bat species in seasonal climates exhibit analogous behaviour when resources decline.
- Explicitly addresses 'bear hibernation', stating it differs from true hibernation seen in species like ground squirrels.
- Describes physiological differences: body temperature drops but not drastically and bears remain in deep sleep; notes the maternal exception (waking to give birth).
- Describes metabolic slowdown in polar bears after fasting and contrasts black/brown bears' limited ability to slow metabolism.
- Provides species-level nuance that supports the idea of bear-specific winter adaptations rather than uniform 'true hibernation' across all bears.
- Explicitly names 'true hibernation' and gives ground squirrels as an example of true hibernation.
- Contrasts bear 'deep sleep' with 'true hibernation (like we see in ground squirrels)', implying a canonical example of hibernation behavior.
- Lists 'rodents, lemmings' among tundra fauna adapted to severe winters, indicating rodents occur in cold environments where hibernation-like strategies are relevant.
- Mentions insulating adaptations in tundra animals, supportive context for winter dormancy strategies in rodents.
- [THE VERDICT]: Sitter (with a technical trap). Standard Environment books (Shankar IAS, Ch 11) explicitly discuss Bear vs. Rodent hibernation. Bats are a logical extension based on 'Resource Logic' (no insects in winter).
- [THE CONCEPTUAL TRIGGER]: Adaptations in Organisms (Ecology). Specifically, physiological responses to abiotic stress: Migration (move), Suspension (hibernate/aestivate), or Regulation.
- [THE HORIZONTAL EXPANSION]: Memorize the 'Dormancy Matrix': 1. Hibernation (Winter): Bears, Bats, Ground Squirrels. 2. Aestivation (Summer): Lungfish, Snails, Earthworms. 3. Brumation (Reptiles): Snakes, Lizards. 4. Diapause: Insects/Zooplankton (suspended development). 5. Torpor: Daily energy drop (Hummingbirds).
- [THE STRATEGIC METACOGNITION]: Apply 'Resource Logic' rather than rote memorization. If a mammal (Bat) eats insects, and insects vanish in winter, the mammal has only two choices: Migrate or Hibernate. If it's small and fragile, hibernation is the likely evolutionary path.
Reference [1] contrasts true hibernation (drastic drop in body temperature, intermittent arousals) with the bear's milder metabolic slowdown described as a deep sleep.
Understanding precise definitions and examples (true hibernation vs. milder dormancy) is high-yield for ecology questions testing animal adaptations and physiological responses to seasons. It helps answer comparison questions and link to metabolism, reproduction timing, and species-specific strategies; learn by comparing species-specific cases (ground squirrels, bears, polar bears).
- Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 11: Schedule Animals of WPA 1972 > Do you know? > p. 171
- Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 8: Biodiversity > Bo y,utr kno*'?:-', rr.' .:=:.==., > p. 149
References [5] and [9] note animals (e.g., snakes) coming out of hibernation and other behavioural changes being used as indicators before earthquakes.
This concept is useful in disaster-management and environment sections where animal behavioural cues are linked to hazard prediction. UPSC may frame questions on bio-indicators or case studies (Haicheng earthquake); prepare by memorising key examples and mechanisms.
- Geography of India ,Majid Husain, (McGrawHill 9th ed.) > Chapter 17: Contemporary Issues > Earthquake Forecasting > p. 14
- Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 8: Natural Hazards and Disaster Management > Prediction > p. 30
Reference [3] documents fruit bats' role in pollination and seed dispersal and their cultural protection in sacred groves; reference [2] lists bats among regional fauna.
Bats appear frequently in biodiversity and conservation topics due to ecosystem services and human–wildlife interactions. Mastering their ecological functions helps answer questions on pollination networks, forest regeneration, and conservation policy; revise species roles, examples, and socio-cultural links.
- Exploring Society:India and Beyond ,Social Science-Class VII . NCERT(Revised ed 2025) > Chapter 8: How the Land Becomes Sacred > THINK ABOUT IT > p. 181
- Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 4: BIODIVERSITY > Biogeographic zones of India > p. 27
Reference [1] directly contrasts 'true hibernation' (drastic temperature drop, periodic waking) with the bear's deeper sleep that involves only modest temperature decline.
High-yield for ecology/animal physiology questions: distinguishes dormancy types (hibernation, torpor, aestivation) and helps answer comparative adaptation questions. Master by memorizing definitions, species examples, and physiological markers to eliminate distractors in MCQs and explain adaptation mechanisms in mains answers.
- Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 11: Schedule Animals of WPA 1972 > Do you know? > p. 171
Reference [3] discusses polar bears' ability to slow metabolism after fasting and contrasts with black/brown bears' responses to food scarcity.
Useful for questions on survival strategies, energy budgets, and climate-change impacts on species. Links to biomes, conservation, and species-specific adaptations. Prepare by comparing species responses, causes (food scarcity vs seasonal cues), and implications for conservation policy answers.
- Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 8: Biodiversity > Bo y,utr kno*'?:-', rr.' .:=:.==., > p. 149
- Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 11: Schedule Animals of WPA 1972 > Do you know? > p. 171
Reference [1] notes an exception where a mother bear wakes during the deep sleep to give birth, highlighting reproductive ecology during dormancy.
Important for questions on life-history strategies and species survival—shows how reproduction can alter typical behavioural patterns. Study by linking reproductive cycles with seasonal behaviours and citing species-specific examples in answers.
- Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 11: Schedule Animals of WPA 1972 > Do you know? > p. 171
Reference [3] explicitly contrasts 'true hibernation' (ground squirrels) with bear 'deep sleep', highlighting distinct physiological types of winter dormancy.
Understanding the difference between true hibernation and other forms of winter dormancy is high-yield for ecology/animal physiology questions; it clarifies exam traps that treat all 'hibernation' as identical. Master by comparing examples (ground squirrels vs bears) and noting differences in body temperature and periodic arousal.
- Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 11: Schedule Animals of WPA 1972 > Do you know? > p. 171
The 'Summer Sibling' is Aestivation. Since hibernation is tested, expect a question on animals that sleep through drought/heat. Prime candidates: West African Lungfish (forms a mucus cocoon), Desert Tortoises, and Snails.
Use the 'Famous Example' filter against Extreme Options. Option D says 'cannot be observed in ANY'. If you recall even one cartoon of a bear sleeping in a cave, D is eliminated. Between the rest, knowing that Rodents (Ground Squirrels) are the *textbook* definition of hibernation in NCERTs forces you to include 3. This leaves only C (1, 2, and 3) as the viable broad-spectrum answer.
Link Phenology to Climate Change (Mains GS3). Warmer winters cause 'Phenological Mismatch'—pollinators (Bats/Bees) emerge from hibernation before flowers bloom, or Bears wake up early leading to increased Human-Wildlife Conflict. This connects Ecology to Disaster Management.