UPSC CSE Prelims
Biodiversity and Conservation Previous Year Questions (PYQs)
Showing solved Previous Year Questions for Chapter: Biodiversity and Conservation
Topic Breakdown: Scroll →
In the nature, which of the following is/are most likely to be found surviving on a surface without soil?
- Fern
- Lichen
- Moss
- Mushroom
Select the correct answer using the code given below
Detailed Explanation:
Answer: Option 3 — 2 and 3
Lichens and mosses are uniquely adapted to survive on bare surfaces without soil. Lichens, being symbiotic associations of fungi and algae/cyanobacteria, can colonize rocks and tree bark by absorbing nutrients directly from air and rain. Mosses, though non-vascular plants, possess specialized structures that enable them to absorb water and nutrients from their immediate environment without requiring soil.
Analysis of Organisms:
1. Fern – Cannot survive without soil: Ferns are vascular plants requiring soil to anchor their roots and absorb water through their well-developed root systems.
2. Lichen – ✅ Can survive without soil: Lichens are symbiotic organisms (fungus + algae/cyanobacteria) that obtain nutrients directly from air and precipitation, thriving on rocks, bark, and other bare surfaces.
3. Moss – ✅ Can survive without soil: Mosses are bryophytes (non-vascular plants) with rhizoids that can attach to bare surfaces and absorb water and minerals directly from the environment.
4. Mushroom – Cannot survive without soil: Mushrooms are fungal fruiting bodies that require organic substrates (decaying matter, soil rich in nutrients) for the mycelium to grow and produce fruiting structures.
📝 Short Notes: Organisms Surviving Without Soil
| Organism | Type | Survival on Bare Surface | Key Characteristics |
|---|---|---|---|
| Fern | Vascular plant (Pteridophyte) | No | Requires soil for root anchorage; has true roots, stems, and leaves |
| Lichen | Symbiotic association | Yes | Fungus + algae/cyanobacteria; absorbs nutrients from air; indicator of air quality |
| Moss | Non-vascular plant (Bryophyte) | Yes | Has rhizoids (not true roots); absorbs water directly; can grow on rocks, bark |
| Mushroom | Fungal fruiting body | No | Requires organic substrate for mycelium; decomposes organic matter |
- Lichens are pioneer species in ecological succession, colonizing bare rocks and weathering them into soil over time.
- Lichens as bioindicators: Highly sensitive to air pollutants like SO₂, NOₓ, and heavy metals; absence indicates poor air quality.
- Mosses reproduce via spores and require moisture for fertilization but can survive desiccation in dry conditions.
- Bryophytes (mosses, liverworts, hornworts) lack vascular tissues (xylem and phloem) but can thrive in moist, shaded environments on various substrates.
- Ferns are more advanced than mosses, having vascular tissues, but still require moist conditions and soil for optimal growth.
With reference to Indian elephants, consider the following statements:
- The leader of an elephant group is a female.
- The maximum gestation period can be 22 months.
- An elephant can normally go on calving till the age of 40 years only.
- Among the States in India, the highest elephant population is in Kerala.
Which of the statements given above is/are correct?
Detailed Explanation:
Answer: Option 1 — 1 and 2 only
Indian elephants live in matriarchal societies where the oldest and most experienced female leads the herd, while males typically live solitary lives or form bachelor groups. The gestation period of elephants is the longest among land mammals, ranging from 18 to 22 months.
✅ Statement 1 – Correct: Elephant herds are matriarchal, led by the oldest and most experienced female (matriarch), while adult males usually live alone or in bachelor groups.
✅ Statement 2 – Correct: Elephants have the longest gestation period among mammals, ranging from 18 to 22 months, with an average of about 22 months.
❌ Statement 3 – Incorrect: Female elephants can continue to reproduce well beyond 40 years of age, often calving into their 50s and sometimes even early 60s, though fertility may decline with age.
❌ Statement 4 – Incorrect: Karnataka has the highest elephant population in India (around 6,000), followed by Assam and Kerala. Kerala ranks third, not first.
📝 Short Notes: Indian Elephants
- Scientific Name: Elephas maximus indicus (subspecies of Asian elephant)
- Protection Status: Schedule I of Wildlife Protection Act, 1972; Appendix I of CITES; IUCN Red List - Endangered
- Social Structure: Matriarchal herds of 6-12 individuals led by the oldest female; adult males are solitary or form temporary bachelor groups
- Reproduction: Gestation period 18-22 months (longest among mammals); females reach sexual maturity at 10-12 years; can reproduce until 50-60 years of age; typically give birth to one calf every 4-5 years
- Distribution in India: Karnataka (highest population ~6,000), Assam (~5,700), Kerala (~3,000), Tamil Nadu, and northeastern states
- Project Elephant: Launched in 1992 to protect elephants, their habitats, and migration corridors; 33 elephant reserves established across 16 states
- Major Threats: Habitat loss and fragmentation, human-elephant conflict, poaching for ivory (though Indian elephants have smaller tusks than African elephants), railway and road accidents
With reference to India’s biodiversity, Ceylon frogmouth, Coppersmith barbet, Gray-chinned minivet and White-throated redstart are
Detailed Explanation:
Answer: Option 1 — Birds
All four species mentioned—Ceylon frogmouth, Coppersmith barbet, Gray-chinned minivet, and White-throated redstart—are birds found in India and neighboring regions. The Ceylon frogmouth is a nocturnal bird of the Western Ghats, the Coppersmith barbet is named for its metallic call, the Gray-chinned minivet is known for its colorful plumage, and the White-throated redstart is characterized by its distinctive red tail.
📝 Short Notes: Indian Bird Species
- Ceylon Frogmouth (Batrachostomus moniliger): A nocturnal bird native to the Western Ghats and Sri Lanka; resembles a frog due to its wide mouth and camouflaged plumage; inhabits dense tropical forests.
- Coppersmith Barbet (Psilopogon haemacephalus): A resident bird across the Indian subcontinent; named for its repetitive metallic 'tuk-tuk-tuk' call resembling a coppersmith's hammer; features crimson forehead and throat with green body.
- Gray-chinned Minivet (Pericrocotus solaris): Found in the Himalayas and Southeast Asia; exhibits sexual dimorphism with males displaying orange-red plumage and females showing yellow; inhabits subtropical and temperate forests.
- White-throated Redstart (Phoenicurus schisticeps): A small passerine bird found in the Himalayas, Nepal, Bhutan, and parts of China; males have black plumage with white throat and bright rufous-red tail; prefers high-altitude scrublands and rocky areas.
- Biodiversity Significance: These species represent India's rich avian diversity across different ecological zones—from tropical forests to high-altitude regions—highlighting the importance of habitat conservation.
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Consider the following pairs:
| Wildlife | Naturally found in |
|---|---|
| 1. Blue-finned Mahseer | Cauvery River |
| 2. Irrawaddy Dolphin | Chambal River |
| 3. Rusty-spotted Cat | Eastern Ghats |
Which of the pairs given above are correctly matched?
Detailed Explanation:
Answer: Option 3 — 1 and 3 only
This question tests knowledge of wildlife species and their natural habitats in India. Out of the three pairs given, only pairs 1 and 3 are correctly matched, while pair 2 incorrectly associates the Irrawaddy Dolphin with the Chambal River.
✅ Pair 1 – Correct: Blue-finned Mahseer is indeed naturally found in the Cauvery River and other rivers of the Deccan Plateau. It is an endangered freshwater fish species.
❌ Pair 2 – Incorrect: Irrawaddy Dolphin is NOT found in the Chambal River. The Chambal River is known for the Gangetic Dolphin. Irrawaddy Dolphins are found in coastal areas of South and Southeast Asia, and in India, they are found in Lake Chilika (Odisha).
✅ Pair 3 – Correct: Rusty-spotted Cat is naturally found in the Eastern Ghats. This small wild cat species is also found in the Western Ghats, central India, and Sri Lanka.
📝 Short Notes: Indian Wildlife Species and Habitats
| Species | Natural Habitat/Distribution | Conservation Status |
|---|---|---|
| Blue-finned Mahseer | Cauvery River, rivers of Deccan Plateau | Endangered (freshwater fish) |
| Irrawaddy Dolphin | Coastal areas of South and Southeast Asia; Lake Chilika (Odisha) in India; Ayeyarwady, Mahakam, and Mekong rivers | Endangered |
| Gangetic Dolphin | Ganges-Brahmaputra-Meghna river system, Chambal River | Endangered; National Aquatic Animal |
| Rusty-spotted Cat | Eastern Ghats, Western Ghats, Central India, Sri Lanka | Near Threatened; one of world's smallest wild cats |
Recently, there was a growing awareness in our country about the importance of Himalayan nettle (Girardinia diversifolia) because it is found to be a sustainable source of
Detailed Explanation:
Answer: Option 4 — textile fibre
The Himalayan nettle (Girardinia diversifolia) is a wild plant native to the Himalayan region that produces some of the longest natural fibres in the plant world, extracted from its stem. These fibres are strong, durable, and biodegradable, making them an excellent sustainable alternative to synthetic textiles and even comparable to flax or hemp fibres. The plant has gained attention in recent years as a source of eco-friendly textile material for the fashion and fabric industry.
📝 Short Notes: Himalayan Nettle (Girardinia diversifolia)
- Habitat: Found in the Himalayan regions of India, Nepal, Bhutan, and parts of China at altitudes of 1200-3000 meters.
- Fibre Characteristics: Produces fibres up to 2.5 meters long, which are among the longest natural plant fibres; they are strong, glossy, and have good moisture absorption properties.
- Textile Applications: Used for making eco-friendly fabrics, ropes, and traditional garments; can be blended with other natural fibres like cotton or wool.
- Sustainability: Requires minimal water, no pesticides, and grows wild; harvesting is done manually without harming the plant's root system, allowing regrowth.
- Economic Potential: Provides livelihood opportunities for Himalayan communities; being promoted as a sustainable alternative to synthetic fibres and cotton.
Consider the following statements:
- As per law, the Compensatory Afforestation Fund Management and Planning Authority exists at both National and State levels.
- People’s participation is mandatory in the compensatory afforestation programmes carried out under the Compensatory Afforestation Fund Act, 2016.
Which of the statements given above is/are correct?
Detailed Explanation:
Answer: Option 1 — 1 only
The Compensatory Afforestation Fund Management and Planning Authority (CAMPA) was established under the Compensatory Afforestation Fund Act, 2016, to manage funds collected for compensatory afforestation activities. The Act mandates the creation of both National CAMPA and State CAMPAs to ensure proper administration and utilization of these funds at respective levels. However, the Act does not explicitly mandate people's participation in compensatory afforestation programmes.
✅ Statement 1 – Correct: The Compensatory Afforestation Fund Act, 2016, establishes CAMPA at both National and State levels. National CAMPA oversees fund management at the national level, while State CAMPAs manage funds within their respective jurisdictions for compensatory afforestation activities.
❌ Statement 2 – Incorrect: The Compensatory Afforestation Fund Act, 2016, does not contain any explicit provision mandating people's participation in compensatory afforestation programmes. The Act primarily focuses on fund management, utilization mechanisms, and institutional structures rather than public participation requirements.
📝 Short Notes: Compensatory Afforestation Fund Management and Planning Authority (CAMPA)
- Legal Framework: Established under the Compensatory Afforestation Fund Act, 2016, to manage funds collected from forest land diverted for non-forest purposes.
- Two-Tier Structure: National CAMPA at the central level and State CAMPAs in each state/union territory for decentralized fund management.
- Fund Sources: Money collected from user agencies as Net Present Value (NPV) and compensatory afforestation charges when forest land is diverted.
- Fund Utilization: Used for compensatory afforestation, assisted natural regeneration, forest management, wildlife protection, and infrastructure development in forests.
- National CAMPA Composition: Chaired by the Union Minister of Environment, Forest and Climate Change, with members from various ministries and experts.
- State CAMPA Composition: Chaired by the Chief Minister of the state, with state forest officials and other relevant stakeholders.
- Key Objective: Ensure transparent and efficient utilization of funds for ecological restoration and conservation of forest resources.
Consider the following statements
- Asiatic lion is naturally found in India only.
- Double-humped camel is naturally found in India only.
- One-horned rhinoceros is naturally found in India only.
Which of the statements given above is/are correct?
Detailed Explanation:
Answer: Option 1 — 1 only
Among the three statements, only the statement about the Asiatic lion is correct as it is naturally found exclusively in India. The double-humped camel and one-horned rhinoceros have natural ranges extending beyond India's borders.
✅ Statement 1 – Correct: The Asiatic lion (Panthera leo persica) is naturally found only in India, with its entire wild population restricted to Gir National Park and surrounding areas in Gujarat, listed as Endangered on the IUCN Red List.
❌ Statement 2 – Incorrect: The double-humped camel (Bactrian camel) is naturally found across Central Asia, particularly in Mongolia and China; while a population exists in Ladakh's Nubra Valley, its natural range is not exclusive to India.
❌ Statement 3 – Incorrect: The one-horned rhinoceros (Indian rhinoceros) is naturally found in both India (Assam, West Bengal, and Uttar Pradesh) and Nepal, making it a shared natural heritage of both countries.
📝 Short Notes: Endemic and Native Species of India
| Species | Natural Range | Conservation Status (IUCN) | Key Facts |
|---|---|---|---|
| Asiatic Lion | India only (Gir, Gujarat) | Endangered | Last wild population globally; successful conservation has increased numbers from ~20 (1913) to over 600 (2020) |
| One-horned Rhinoceros | India and Nepal | Vulnerable | Found in Kaziranga, Manas, Pobitora (Assam), Jaldapara (West Bengal), Dudhwa (UP), and Chitwan (Nepal) |
| Double-humped Camel (Bactrian) | Central Asia (Mongolia, China) | Critically Endangered (Wild), Domesticated (India) | Nubra Valley population in Ladakh is domesticated; wild populations exist only in Mongolia and China |
| Hangul (Kashmir Stag) | India only (Kashmir) | Critically Endangered | Found only in Dachigam National Park; population critically low (~200) |
| Nilgiri Tahr | India only (Western Ghats) | Endangered | Endemic to Western Ghats, state animal of Tamil Nadu |
| Lion-tailed Macaque | India only (Western Ghats) | Endangered | Endemic to rainforests of Western Ghats in Karnataka, Kerala, Tamil Nadu |
Consider the following statements:
- Some species of turtles are herbivores.
- Some species of fish are herbivores.
- Some species of marine mammals are herbivores.
- Some species of snakes are viviparous.
Which of the statements given above are correct?
Detailed Explanation:
Answer: Option 4 — 1, 2, 3 and 4
All four statements are factually correct as they accurately describe the dietary habits and reproductive characteristics of various animal species. Each statement can be verified through well-documented examples from the animal kingdom.
✅ Statement 1 – Correct: Many turtle species like green sea turtles and Galapagos tortoises are herbivores, feeding primarily on plants, leaves, and fruits.
✅ Statement 2 – Correct: Numerous fish species such as surgeonfish, parrotfish, and tangs are herbivorous, feeding on algae and seaweed in marine ecosystems.
✅ Statement 3 – Correct: Some marine mammals like manatees and dugongs (sea cows) are herbivores, feeding exclusively on seagrasses and aquatic vegetation.
✅ Statement 4 – Correct: Several snake species including boas, vipers, and sea snakes are viviparous, giving birth to live young instead of laying eggs.
📝 Short Notes: Biodiversity - Feeding Types and Reproductive Modes
| Category | Examples | Key Characteristics |
|---|---|---|
| Herbivorous Reptiles | Green sea turtle, Galapagos tortoise, Marine iguana | Feed on plants, algae, seagrass; adapted digestive systems |
| Herbivorous Fish | Parrotfish, Surgeonfish, Tangs, Rabbitfish | Graze on algae and seaweed; crucial for coral reef health |
| Herbivorous Marine Mammals | Manatees, Dugongs (Order Sirenia) | Feed on seagrass; gentle, slow-moving aquatic herbivores |
| Viviparous Snakes | Boas, Vipers, Sea snakes, Garter snakes | Give birth to live young; embryos develop inside mother |
- Herbivory in Marine Ecosystems: Herbivorous species play crucial roles in maintaining ecosystem balance by controlling algal growth and vegetation.
- Viviparity vs Oviparity: While most reptiles are oviparous (egg-laying), viviparity has evolved in several snake families as an adaptation to specific environmental conditions.
- Green Sea Turtle: Adults are almost exclusively herbivorous, feeding on seagrasses and algae, though juveniles may be omnivorous.
- Ecological Importance: Herbivorous fish are essential for coral reef health as they prevent algal overgrowth that can smother corals.
Why is a plant called Prosopis juliflora often mentioned in the news?
Detailed Explanation:
Answer: Option 2 — It tends to reduce the biodiversity in the area in which it grows.
Prosopis juliflora, commonly known as mesquite, is frequently mentioned in news due to its invasive nature and negative impact on native ecosystems. Originally introduced for afforestation and erosion control, it rapidly spreads and forms dense thickets that outcompete native vegetation, thereby reducing biodiversity. Its aggressive growth pattern disrupts ecological balance and has led to efforts in states like Tamil Nadu to remove it and restore native habitats.
📝 Short Notes: Prosopis juliflora (Mesquite)
- Origin: Native to Central and South America; introduced to Africa, Asia, and Australia for afforestation, erosion control, and fuelwood.
- Common names: Mesquite, Thorn Mimosa, Vilayati Babul, Seemai Karuvelam (Tamil Nadu).
- Invasive characteristics: Rapid growth rate, drought tolerance, prolific seed production, and deep root system allowing survival in harsh conditions.
- Ecological impact: Forms dense thickets that prevent growth of native plants; reduces biodiversity; depletes soil moisture and nutrients; alters habitat structure.
- Current status in India: Declared invasive species in several states; particularly problematic in Tamil Nadu, Gujarat, and Rajasthan; removal and restoration programs underway.
- Uses: Despite invasive nature, used for fuelwood, charcoal, fodder (pods), and timber; pods contain high protein content.
The term "sixth mass extinction/sixth extinction" is often mentioned in the news in the context of the discussion of
Detailed Explanation:
Answer: Option 4 — Mankind's over-exploitation/misuse of natural resources, fragmentation/loss of natural habitats, destruction of ecosystems, pollution and global climate change.
The term "sixth mass extinction" refers to the ongoing biodiversity crisis driven primarily by anthropogenic (human-caused) factors. Unlike previous mass extinctions caused by natural phenomena, the current extinction event is characterized by unprecedented rates of species loss due to human activities including habitat destruction, overexploitation of species, pollution, introduction of invasive species, and climate change. Scientists estimate that species are currently going extinct at rates 100 to 1,000 times higher than the natural background rate, making this a human-driven ecological catastrophe comparable to the five previous mass extinctions in Earth's 4.5-billion-year history.
📝 Short Notes: Mass Extinctions
| Extinction Event | Time Period | Species Lost | Cause |
|---|---|---|---|
| Ordovician-Silurian | ~445 million years ago | ~85% | Climate change, glaciation |
| Late Devonian | ~375 million years ago | ~75% | Ocean anoxia, climate change |
| Permian-Triassic ("Great Dying") | ~252 million years ago | ~96% | Volcanic eruptions, climate change |
| Triassic-Jurassic | ~201 million years ago | ~80% | Volcanic activity, climate change |
| Cretaceous-Paleogene | ~66 million years ago | ~76% (including dinosaurs) | Asteroid impact, volcanic activity |
| Sixth Extinction (Holocene) | Ongoing (present) | Unknown (in progress) | Human activities |
- Current extinction rate: 100-1,000 times higher than natural background rate
- Primary drivers: Habitat loss (deforestation, urbanization), overexploitation (hunting, fishing), pollution, invasive species, climate change
- Most affected groups: Amphibians, marine mammals, large predators, island species
- IUCN Red List: Over 40,000 species currently threatened with extinction
- Holocene extinction: Another name for the sixth extinction, referring to the current geological epoch
Recently there was a proposal to translocate some of the lions from their natural habitat in Gujarat to which one of the following sites?
Detailed Explanation:
Answer: Option 4 — Kuno Palpur Wildlife Sanctuary
The Ministry of Environment approved Kuno Palpur Wildlife Sanctuary (now Kuno National Park) in Madhya Pradesh as the second home for translocating Asiatic lions from Gir National Park in Gujarat. This translocation was proposed to create a second viable population of Asiatic lions to ensure their long-term survival and reduce the risk of extinction from disease outbreaks or natural disasters at a single location. However, the translocation has faced delays due to various administrative and conservation concerns.
The term 'M-STRIPES’ is sometimes seen in the news in the context of
Detailed Explanation:
Answer: Option 2 — Maintenance of Tiger Reserves
M-STRIPES stands for Monitoring System for Tigers - Intensive Protection and Ecological Status. It is a software-based monitoring system launched by the National Tiger Conservation Authority (NTCA) to strengthen tiger protection and enhance patrolling activities in tiger reserves across India. The system enables real-time monitoring of patrol efforts, wildlife sightings, and ecological parameters by forest guards and staff in tiger reserves.
In India, if a species of tortoise is declared protected under Schedule I of the Wildlife (Protection) Act, 1972, what does it imply?
Detailed Explanation:
Answer: Option 1 — It enjoys the same level of protection as the tiger.
Schedule I of the Wildlife (Protection) Act, 1972, provides the highest level of legal protection to endangered species in India. Any species listed under Schedule I, whether a tiger, elephant, or tortoise, receives identical legal safeguards including absolute protection from hunting, trade, and habitat destruction, with the most stringent penalties for violations.
❌ Option 2 – Incorrect: This describes the IUCN Red List category 'Extinct in the Wild', which is a biological conservation status, not a legal designation under the Wildlife (Protection) Act.
❌ Option 3 – Incorrect: Endemism (being restricted to a particular geographic region) is not a criterion for Schedule I listing; species are listed based on the degree of threat and need for protection, regardless of their geographic range.
❌ Option 4 – Incorrect: Since both statements B and C are incorrect, this option is also incorrect.
Note: The Wildlife (Protection) Amendment Act, 2022, has rationalized the original six schedules into four schedules, but Schedule I continues to provide the highest level of protection.
If you want to see gharials in their natural habitat, which one of the following is the best place to visit?
Detailed Explanation:
Answer: Option 2 — Chambal River
The National Chambal Gharial Sanctuary, located along the Chambal River spanning Madhya Pradesh, Rajasthan, and Uttar Pradesh, is the best place to see gharials in their natural habitat. This tri-state protected area is one of the most important sanctuaries dedicated to the conservation of the critically endangered gharial, a fish-eating crocodilian species. The sanctuary provides ideal riverine conditions for gharial breeding and survival, making it the premier destination for observing these unique reptiles in the wild.
With reference to an initiative called ‘The Economics of Ecosystems and Biodiversity (TEEB)’, which of the following statements is/are correct?
- It is an initiative hosted by UNEP, IMF and World Economic Forum.
- It is a global initiative that focuses on drawing attention to the economic benefits of biodiversity.
- It presents an approach that can help decision-makers recognize, demonstrate and capture the value of ecosystems and biodiversity.
Select the correct answer using the code given below
Detailed Explanation:
Answer: Option 3 — 2 and 3 only
❌ Statement 1 – Incorrect: TEEB was launched in 2007 by Germany and the European Commission following a proposal by the G8+5 Environment Ministers. The TEEB office is hosted by the United Nations Environment Programme (UNEP) only, not by the IMF or the World Economic Forum.
✅ Statement 2 – Correct: TEEB is a global initiative that focuses on drawing attention to the economic benefits of biodiversity. It highlights the growing cost of biodiversity loss and ecosystem degradation by bringing together expertise from science, economics, and policy.
✅ Statement 3 – Correct: TEEB presents a tiered approach that helps decision-makers recognize, demonstrate, and capture the value of ecosystems and biodiversity. This approach facilitates the integration of ecosystem values into policy-making and economic accounting.