Biodiversity, plants & animals

Answer: (a) Ant

Ants are the well-known fungus farmers among these options. The fungus-gardening (attine) ants, including leafcutter ants of the American tropics, grow fungus in their nests as their food.

• ✓ (a) Attine ants, more than 250 species, cultivate fungi as their main food. Leafcutter ants cut leaves, carry them into underground nests and use them to feed the fungus.
• ✗ (b) Cockroaches are not known as fungus cultivators.
• ✗ (c) Crabs are not known as fungus cultivators.
• ✗ (d) Spiders are not known as fungus cultivators.

Remember · Fungus-growing (attine) ants, such as leafcutter ants, farm fungus in their nests as food. This is an example of mutualism between an insect and a fungus.

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Answer: (d) 2 and 3

DNA barcoding identifies which species a sample belongs to by reading a short, standard piece of DNA. So it can tell apart look-alike (cryptic) species and can spot unwanted or undeclared species in processed food, but it does not tell the age of an organism.

• ✗ 1. A DNA barcode is a short standardised DNA marker used for detection and identification of species. It says what the organism is, not how old it is.
• ✓ 2. Barcodes can separate cryptic species, which look alike outwardly; a DNA mini-barcode with next-generation sequencing has been used to detect such species even in mixed seafood.
• ✓ 3. Processed foods are more likely to be substituted or adulterated with undeclared species, and DNA barcoding is used to check meat, poultry and fish products for such species.

Remember · DNA barcoding = species identification from a short standard DNA sequence (COI in animals). Uses: telling look-alike (cryptic) species apart and checking foods for undeclared species. Not for age.

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Answer: (c) 2 and 3

Lichens and mosses are pioneer organisms: they cling to bare rock, walls and bark and are among the first to colonise weathered rock before any soil exists. Ferns arrive only after some soil and humus has built up, and mushrooms need dead organic matter to feed on.

• ✗ 1. Ferns are vascular plants with roots; in soil formation they appear later, once humus has accumulated.
• ✓ 2. A lichen is a partnership of a fungus and an alga that grows directly on rocks and tree bark.
• ✓ 3. Mosses have root-like rhizoids rather than true roots and form green mats on damp rocks and old walls.
• ✗ 4. Mushrooms are fungi that cannot make food; they absorb nutrients from dead and decaying matter, so they grow on soil, litter or wood.

Remember · Pioneers on bare rock: lichens and mosses. They start soil formation; ferns, grasses and trees follow.

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Answer: (c) Lemongrass

Lemongrass (Cymbopogon species) yields an aromatic essential oil rich in citral, and this oil is used in insect-repellent preparations and has been shown to repel mosquitoes. Congress grass (Parthenium) is a weed, and elephant grass is a fodder grass.

• ✓ (c) Lemongrass oil, distilled from the leaves, has a strong lemon-like smell from its citral and goes into insect-repellent preparations (National Horticulture Board); laboratory studies show it repels mosquitoes.
• ✗ (a) Congress grass is Parthenium hysterophorus (carrot grass), an invasive weed that causes pollen allergy; it is not used to repel insects.
• ✗ (b) Elephant grass (Napier grass, Pennisetum purpureum) is a tall tropical grass that gives good fodder for grazing animals when young; it is not a repellent.

Remember · Lemongrass (Cymbopogon) oil, rich in citral, is a plant-based mosquito repellent. Congress grass (Parthenium) is an invasive weed; elephant (Napier) grass is fodder.

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Answer: (d) 1 and 3

Both the hedgehog (covered in spines) and the pangolin (covered in hard scales) curl into a tight ball when threatened, so that only the armour faces the predator and the soft parts are hidden. The marmot, a burrowing rodent, instead whistles an alarm and runs into its burrow.

• ✓ 1. When frightened, a hedgehog rolls into a tight ball with its snout and limbs tucked under its body, which makes its spines erect and shields the soft parts.
• ✗ 2. Marmots are burrowing rodents; when danger is near, a sentinel marmot whistles sharply so that colony members can escape into the nearest burrow, rather than rolling up.
• ✓ 3. The Indian pangolin is armoured with overlapping horny scales and rolls into a ball when threatened.

Remember · Roll-up defence: hedgehog (spines) and pangolin (scales). Marmots whistle an alarm and flee to burrows.

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Answer: (c) Oyster

A filter feeder draws in water and strains out tiny food particles such as plankton and algae. The oyster, a bivalve mollusc fixed to one spot, feeds exactly this way, pumping water through its gills; the others actively hunt or scavenge.

• ✓ (c) Oysters feed by filtering algae out of the water; one oyster can filter up to about 50 gallons (roughly 190 litres) a day, which also cleans estuary water.
• ✗ (b) The octopus is an active predator that catches crabs, shellfish and fish with its arms.
• ✗ (d) Pelicans scoop up fish in their throat pouch and drain the water out; they are fish-eaters, not strainers of plankton.

Remember · Filter feeders strain food from water: oysters, mussels, clams, sponges, krill, baleen whales, whale sharks, flamingos. Oyster reefs clean estuary water.

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Answer: (d) 1, 2 and 3

All three groups contain species that live in close, often mutually beneficial, partnerships with other organisms. Reef-building corals (cnidarians) host photosynthetic zooxanthellae; fungi form lichens and mycorrhizae; and many protozoa live as symbionts, some carrying algae inside their own cells.

• ✓ 1. Corals, which are cnidarians, house zooxanthellae in their tissues; the algae supply sugars from photosynthesis and the coral gives them shelter and carbon dioxide.
• ✓ 2. Fungi team up with algae or cyanobacteria to form lichens, and with plant roots to form mycorrhizae that help plants absorb phosphorus.
• ✓ 3. Many protozoa live as symbionts; the ciliate Paramecium bursaria, for instance, carries symbiotic Chlorella algae in its cytoplasm. The two benefit each other: the ciliate gives the algae a protected habitat and the algae add to its nutrition through photosynthesis.

Remember · Mutualism examples: coral + zooxanthellae, fungus + alga (lichen), fungus + root (mycorrhiza), Paramecium bursaria + algae, legume + Rhizobium.

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Answer: (b) 3, 4 and 5

UPSC's key marks statements 3, 4 and 5 correct, while 1 and 2 are wrong: moringa is a deciduous tree of its own family, not a legume, and tamarind is not endemic to South Asia, having originated in Madagascar (Spices Board).

• ✗ 1. Moringa (Moringa oleifera) is a small deciduous tree of the family Moringaceae, so it is neither a legume nor evergreen.
• ✗ 2. The Spices Board says tamarind originated in Madagascar and is now cultivated widely in India and other countries, so it is not endemic to South Asia.
• ✓ 3. Tamarind, with seeds and de-seeded, is on the Ministry of Tribal Affairs' list of minor forest produce with a minimum support price, the gathering of which is a livelihood for tribal collectors.
• ✓ 4. UPSC's official key treats this statement as correct; we could not confirm the detail from an official source, so we do not explain it here.
• ✓ 5. UPSC's official key treats this statement as correct; we could not confirm the detail from an official source, so we do not explain it here.

Remember · Moringa is a deciduous Moringaceae tree, not a legume; tamarind originated in Madagascar and is a listed minor forest produce with an MSP.

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Answer: (a) 1 and 2 only

Statements 1 and 2 are correct: an elephant herd is led by the oldest female (the matriarch), and gestation lasts about 22 months. Statement 3 is wrong because females keep reproducing until their 60s, and statement 4 is wrong because Karnataka, not Kerala, has India's largest elephant population.

• ✓ 1. An elephant herd is led by its oldest female, the matriarch, and consists of her calves and grand-calves; young bulls leave at puberty.
• ✓ 2. MoEFCC puts the gestation period of elephants at about 22 months, so 22 months is the maximum.
• ✗ 3. Female elephants begin reproducing at about 15 years of age and continue until they are in their 60s, so a cut-off at 40 years is not the norm. UPSC's key treats this statement as wrong.
• ✗ 4. Among Indian States, Karnataka has the largest elephant population in the 2017 synchronized census (6,049, against 5,706 for Kerala and 5,719 for Assam, per MoEFCC's Project Elephant table); Kerala is not the leader.

Remember · Elephants: matriarch-led herds; gestation about 22 months; females reproduce till their 60s; Karnataka has the most elephants among Indian States.

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Answer: (a) Birds

All four are birds: a nocturnal frogmouth, a barbet (a small fruit-eating bird), a minivet (a small insect-eating songbird) and a redstart (a chat-like songbird).

• ✓ (a) The Ceylon frogmouth (Batrachostomus moniliger) is a Western Ghats bird, the coppersmith barbet is listed among the birds of Keoladeo, the White-throated redstart (Phoenicurus schisticeps) is a Himalayan bird, and the Gray-chinned minivet (Pericrocotus solaris) is a forest bird of the eastern Himalaya.
• ✗ (d) The word 'frogmouth' misleads: it names the wide, frog-like beak of this night bird, not a frog. None of the four is an amphibian, reptile or primate.

Remember · Frogmouths, barbets, minivets and redstarts are all birds; a bird's common name can mislead, so check the scientific name (Batrachostomus is a bird genus).

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Answer: (a) Kanha National Park

Kanha National Park (Madhya Pradesh) is the home of the hard-ground barasingha, Rucervus duvaucelii branderi, the swamp-deer sub-species that lives on firm ground and feeds only on grass. It is Madhya Pradesh's State animal.

• ✓ (a) The Madhya Pradesh Forest Department calls the hard-ground barasingha the State animal and says it is found exclusively in Kanha; until recently Kanha held the only world population of this sub-species.
• ✗ (b) Manas (Assam) also shelters swamp deer, so it tempts, but it is known for the rhino, tiger, pygmy hog and Bengal florican; the hard-ground form is Kanha's.
• ✗ (c) Mudumalai (Tamil Nadu, Nilgiris) is known for elephant, gaur and tiger; its official fauna list has no swamp deer.
• ✗ (d) Tal Chhapar (Churu, Rajasthan) is known as a haven for blackbuck and birds, not for barasingha.

Remember · Hard-ground barasingha (Rucervus duvaucelii branderi) is Kanha's flagship deer and Madhya Pradesh's State animal.

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Answer: (a) 1 and 2 only

Musk deer (Moschus chrysogaster) is a high-Himalayan animal, so the Uttarakhand mountain areas, Askot Wildlife Sanctuary and Gangotri National Park, are its likely homes, not the plains and foothill areas of Kishanpur and Manas.

• ✓ 1. Askot Wildlife Sanctuary in Pithoragarh district, Uttarakhand, is listed as a home of musk deer, alongside snow leopard, bharal and tahr.
• ✓ 2. The Wildlife Institute of India lists Musk deer (Moschus chrysogaster) among the mammals documented in Gangotri National Park, Uttarakhand.
• ✗ 3. Kishanpur is a lowland sanctuary in Uttar Pradesh, part of Dudhwa Tiger Reserve on the Gangetic alluvial plain; its deer are swamp deer, hog deer, spotted deer and the like, not musk deer.
• ✗ 4. Manas (Assam) is known for tiger, greater one-horned rhino, swamp deer, pygmy hog and Bengal florican; musk deer is not among its species.

Remember · Musk deer lives in high, cold Himalayan forests (Uttarakhand, Kashmir, Sikkim); look for Askot and Gangotri, not the Terai or Assam plains.

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Answer: (a) A licence is required to cultivate that plant.

A plant placed in Schedule VI, the list of 'specified plants', can be cultivated only with a licence. The Wildlife (Protection) Act, 1972 does not ban its cultivation outright, and the listing has nothing to do with genetic modification or invasiveness.

• ✓ (a) Section 17C says no person shall cultivate a specified plant except under a licence granted by the Chief Wild Life Warden or an officer authorised by the State Government.
• ✗ (b) Cultivation is allowed, but only with that licence; the Act regulates it rather than forbidding it in all circumstances.
• ✗ (c) Schedule VI is a conservation list of protected wild plants; it says nothing about genetic modification.
• ✗ (d) Plants are listed to protect them, not because they are invasive or harmful to the ecosystem.
• • Since then The Wild Life (Protection) Amendment Act, 2022 (in force from 1 April 2023) cut the schedules to four; 'specified plant' now means a plant in Schedule III instead of Schedule VI, and the licence rule of Section 17C continues.

Remember · Schedule VI plants (now Schedule III) are 'specified plants': cultivation needs a licence from the Chief Wild Life Warden, and picking or uprooting them in forests is prohibited.

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Answer: (c) 1 and 3 only

Desert National Park in Rajasthan lies in two districts, Jaisalmer and Barmer, and shelters the Great Indian Bustard, but it is not free of people. Dozens of villages and hamlets exist inside its boundary, so statement 2 fails.

• ✓ 1. The Park covers 3,162 sq km, of which 1,900 sq km is in Jaisalmer district and 1,262 sq km in Barmer district of Rajasthan.
• ✗ 2. People live inside the Park. The official nomination lists 73 villages and other settlements (dhanis) within it, though the population density is low, about 4-5 persons per sq km.
• ✓ 3. The Park has a good population of the Great Indian Bustard, called Godawan locally, and it is one of the bird's natural habitats.

Remember · Desert National Park (Rajasthan, gazetted 1980): Jaisalmer and Barmer districts, villages inside it, and a stronghold of the Great Indian Bustard.

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Answer: (c) Nagarjunsagar-Srisailam

Nagarjunsagar-Srisailam has the largest Critical Tiger Habitat of the four, at 2,595.72 sq km. The other three are far smaller: Sunderban 1,699.62, Ranthambore 1,113.36 and Corbett 821.99 sq km.

• ✓ (c) The National Tiger Conservation Authority lists a core area of 2,595.72 sq km for Nagarjunsagar-Srisailam; the core is the notified Critical Tiger Habitat. It is the largest core area among India's tiger reserves.
• ✗ (d) Sunderban has a core of 1,699.62 sq km. Its total area (2,584.89 sq km) is close to the winner's core figure, which makes it a tempting choice, but the question asks about the critical habitat only.
• ✗ (a) Corbett is the oldest tiger reserve in the group but its core is only 821.99 sq km.
• ✗ (b) Ranthambore has a core of 1,113.36 sq km.

Remember · A tiger reserve = core or Critical Tiger Habitat (inviolate) + buffer. Nagarjunsagar-Srisailam has the largest core, 2,595.72 sq km.

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Answer: (a) 1 only

Only the Asiatic lion is confined to India today, surviving in and around Gir in Gujarat. The double-humped (Bactrian) camel is a Central Asian animal that survives in India only in Ladakh's Nubra valley, and the one-horned rhinoceros also lives in Nepal's Terai, for example in Chitwan.

• ✓ 1. The Asiatic lion once ranged from West Asia to central India, but since the early 20th century its wild range has shrunk to the Gir National Park and surrounding areas of Gujarat.
• ✗ 2. The Bactrian or two-humped camel belongs to Central Asia; India's small herd in the Nubra valley of Ladakh is a remnant of the old Central Asian trade routes, so the species is not found only in India.
• ✗ 3. The greater one-horned rhinoceros lives in northern India (Kaziranga, Manas, Jaldapara and others) and in southern Nepal, where Chitwan holds one of its last populations.

Remember · India-only: Asiatic lion (Gir). Shared: one-horned rhino (India + Nepal), Bactrian camel (Central Asia; in India only Nubra, Ladakh).

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Answer: (a) Neyyar, Peppara and Shendurney Wildlife Sanctuaries; and Kalakad Mundanthurai Tiger Reserve

Agasthyamala Biosphere Reserve, at the southern end of the Western Ghats, takes in three Kerala wildlife sanctuaries (Shendurney, Peppara and Neyyar) and the Kalakad Mundanthurai Tiger Reserve of Tamil Nadu.

• ✓ (a) UNESCO's description of the reserve names exactly these: the Shendurney, Peppara and Neyyar wildlife sanctuaries and the Kalakad Mundanthurai Tiger Reserve. The reserve spans districts of Tamil Nadu and Kerala.
• ✗ (b) This mixes sites from the Nilgiri and Wayanad hills further north in the Western Ghats; none is part of Agasthyamala.
• ✗ (c) Kaundinya, Gundla Brahmeswaram and Papikonda are sanctuaries of Andhra Pradesh, and Mukurthi is in the Nilgiris of Tamil Nadu, so the set cannot belong to Agasthyamala.
• ✗ (d) Kawal, Sri Venkateswara and Nagarjunasagar-Srisailam are in Telangana and Andhra Pradesh, far from Agasthyamala.

Remember · Agasthyamala BR (Tamil Nadu and Kerala): Shendurney, Peppara, Neyyar sanctuaries plus Kalakad Mundanthurai Tiger Reserve.

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Answer: (d) 1, 2, 3 and 4

All four statements are correct. The word 'some' in each only requires that at least one species fits, and each has a well-known example: the green turtle, the grass carp, the dugong and the sea snakes.

• ✓ 1. The green turtle is a herbivore, eating mostly seaweed, seagrasses and algae.
• ✓ 2. Many fish are plant eaters; the grass carp, for example, is a basically herbivorous fish that feeds on aquatic weeds.
• ✓ 3. The dugong (sea cow) is a marine mammal that depends largely on seagrass for food.
• ✓ 4. Viviparous means the young develop inside the mother and are born alive. Sea snakes such as the dusky sea snake do this, and so do boas and many vipers.

Remember · 'Some species' statements are usually true: herbivorous green turtle, grass carp and dugong; viviparous sea snakes.

Question and answer: UPSC's official GS Paper I (2019, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink · Report an error

Answer: (c) 1 and 3 only

Why not the tempting option · UPSC's key is (c). Pair 1 holds on the reading 'lives wild in the Cauvery': the blue-finned mahseer is now the river's dominant mahseer and breeds there. Strictly it is not native to the Cauvery, since peer-reviewed work shows it was stocked from a Maharashtra hatchery from the 1970s–80s and the river's own mahseer is the hump-backed Tor remadevii; but no option offers '3 only', and with pair 2 clearly wrong, (c) is the only answer the options allow. In the exam, when one pair is contestable on fine taxonomy, let the options decide.

UPSC's key accepts pairs 1 and 3 and rejects pair 2. The blue-finned mahseer is the mahseer most often found in the Cauvery today, where it breeds in the wild; the Irrawaddy dolphin's Indian stronghold is Chilika Lagoon, not the Chambal; and the Rusty-spotted Cat does occur in the Eastern Ghats.

• ✓ 1. The blue-finned mahseer (Tor khudree, the Deccan mahseer) is now the common mahseer of the Cauvery: a self-sustaining wild population, which a 2015 study of the river's angler catches found to be recruiting strongly, after decades of stocking by Karnataka's fisheries department and angling bodies.
• ✗ 2. Chilika Lagoon on the east coast is the largest habitat of the endangered Irrawaddy dolphin in India. The Chambal is known for the gharial and the Ganges river dolphin, not this species.
• ✓ 3. The Rusty-spotted Cat lives in forests of peninsular India, including the Eastern Ghats; it has been recorded on camera in Papikonda National Park in the northern Eastern Ghats of Andhra Pradesh.

Remember · Irrawaddy dolphin: Chilika Lagoon (Odisha). Rusty-spotted Cat: peninsular forests including the Eastern Ghats. Blue-finned mahseer: the common mahseer of the Cauvery today.

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Answer: (d) textile fibre

Himalayan nettle (Girardinia diversifolia) is prized for the strong bast fibre in its stems, which is spun and woven into cloth, so it is a sustainable source of textile fibre.

• ✓ (d) The bast fibre of its bark is used for clothing, ropes, mats and sacks, and the Ministry of Textiles has supported research on products from Himalayan nettle among natural fibres.
• ✗ (a) Anti-malarial drugs come from plants like cinchona (quinine) and Artemisia (artemisinin), not from Himalayan nettle.
• ✗ (b) Biodiesel comes from oil-bearing seeds such as jatropha and pongamia; nettle is valued for its fibre, not for oil.

Remember · Himalayan nettle (Girardinia diversifolia, 'bichhu buti') yields bast fibre for textiles; Uttarakhand and the Ministry of Textiles have promoted it.

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Answer: (d) 1, 2 and 3

All three are ways in which dry-area plants cut water loss through transpiration. A waxy coat seals the surface, small leaves expose less evaporating surface, and thorns or spines replace leaves almost entirely.

• ✓ 1. A thick, waxy cuticle on hard leaves slows the escape of water vapour; plants of very dry habitats often have such a coat.
• ✓ 2. Small leaves have less surface from which water can evaporate and heat up less in the sun.
• ✓ 3. In plants such as cacti the leaves are reduced to thorns or spines, so the plant loses very little water through leaves at all.

Remember · Desert (xerophytic) plants save water with waxy coats, small leaves, thorns/spines, deep roots and fleshy water-storing stems.

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Answer: (d) Mankind's over-exploitation/misuse of natural resources, fragmentation/loss of natural habitats, destruction of ecosystems, pollution and global climate change.

The "sixth extinction" is the loss of species happening now, at a pace far above the natural rate, and it is driven by human activity: habitat loss and fragmentation, over-exploitation, invasive species and the like. Option (d) names these human pressures. Earlier mass extinctions were natural events, and the current one is what makes this episode different.

• ✓ (d) Species are now disappearing an estimated 100 to 1,000 times faster than before humans, and human activities are responsible. Habitat loss and fragmentation, over-exploitation, alien species and co-extinctions are the main causes.
• ✗ (b) This describes a feared natural event, a meteorite impact. The sixth extinction is not a fear about the future but an ongoing loss caused by people.
• ✗ (a) Monoculture and chemical use damage ecosystems, but they are only some of the pressures. They do not define the term, which covers the whole human-driven loss of species.
• ✗ (c) Loss of native crop varieties is a narrower concern, agricultural biodiversity. The sixth extinction is about species loss across all ecosystems.

Remember · Five natural mass extinctions came before; the sixth is human-driven, at 100 to 1,000 times the pre-human rate. The four main causes are the 'Evil Quartet'.

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Answer: (b) It tends to reduce the biodiversity in the area in which it grows.

Prosopis juliflora (vilayati babul or vilayati kikar) is an invasive alien tree from South America. It spreads fast and pushes out native plants and the animals that depend on them, so it is in the news for removal drives.

• ✓ (b) The Wildlife Institute of India calls it one of the worst invaders affecting ecosystems and local biodiversity in Tamil Nadu. NCERT explains that alien species that turn invasive cause decline or extinction of native species.
• ✗ (a) The plant is not in the news for any cosmetics extract; in India it was introduced for fuelwood and to green degraded land.
• ✗ (c) It is not in the news as a source of pesticide raw material; it is in the news for the harm it does as an invader.

Remember · Prosopis juliflora (vilayati babul) is an invasive alien tree that displaces native species and lowers biodiversity.

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Answer: (d) 1, 2 and 3

All three statements are taken as correct. NCERT places coral reefs in the tropical oceans; half of all reef area is in just five countries, and Australia, Indonesia and the Philippines alone hold about 42% of it; and reefs host 32 of the 34 recognised animal phyla (UN).

• ✓ 1. NCERT describes atolls as low islands of coral reefs found in the tropical oceans, so most reefs lie in tropical waters.
• ✓ 2. Half of the world's reef surface lies in only five countries: Australia, Indonesia, the Philippines, France and Papua New Guinea. The GCRMN ranking gives Australia 16.88%, Indonesia 15.26% and the Philippines 9.74% of reef surface, a cumulative 41.88% for the three, which is more than one-third.
• ✓ 3. The UN's World Ocean Assessment says reefs host 32 of the 34 recognised phyla, nearly all of them. UPSC's official key treats this statement as correct; we could not confirm the comparison with rainforests from an official source, so we do not explain it here.

Remember · Reefs: mostly tropical, concentrated in a few countries (Australia, Indonesia, Philippines hold about 42%), and home to 32 of 34 animal phyla.

📘 Read it in NCERT: Class 11 Fundamentals of Physical Geography, Ch 12 (practise this chapter)

Question and answer: UPSC's official GS Paper I (2018, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 1 Oct 2026 (how we verify). Permalink · Report an error

Answer: (b) 2 only

TRAFFIC is a non-governmental wildlife trade monitoring network founded by IUCN and WWF, not a UN body. Its whole purpose is to keep the trade in wild species from harming their survival, so only statement 2 is right.

• ✗ 1. TRAFFIC was set up in 1976 by IUCN and WWF, which remain its founders and partners. It describes itself as a non-governmental organisation and has no place in the UNEP structure.
• ✓ 2. TRAFFIC's own 2017 website stated this as its mission, word for word. It now phrases the same aim as keeping trade in wild species legal and sustainable.

Remember · TRAFFIC = NGO wildlife-trade monitoring network, founded 1976 by IUCN and WWF; works closely with CITES but is not a UN or UNEP body.

Question and answer: UPSC's official GS Paper I (2017, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink · Report an error

Answer: (c) 1 and 3 only

Butterflies are pollinators and also food for many predators, so their decline would hurt pollination and the animals that eat them. They play no role in keeping fungal diseases of crops in check, so statement 2 does not follow.

• ✓ 1. Butterflies are among the common animal pollinators of flowering plants, so plants that depend on them could set fewer seeds.
• ✗ 2. Butterflies and their caterpillars feed on nectar and leaves; they do not control plant-infecting fungi, so their loss gives no reason for fungal infections to rise.
• ✓ 3. Birds, spiders, wasps and dragonflies prey on butterflies or their caterpillars; when a prey species crashes, predators that rely on it can decline too.

Remember · Removing one species ripples through the web: butterflies = pollinators + prey. Their crash hits pollination and predator populations, not fungal disease.

📘 Read it in NCERT: Class 12 Biology, Ch 1 (practise this chapter) · Class 12 Biology, Ch 11 (practise this chapter) · Class 8 Curiosity, Ch 12 (practise this chapter)

Question and answer: UPSC's official GS Paper I (2017, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink · Report an error

Answer: (d) 1, 2 and 3

All three are listed in Schedule I of the Wildlife (Protection) Act, 1972, which gives the highest protection. Hunting them is banned except in the two cases the Act itself allows: a Chief Wild Life Warden's order under Section 11, or a special permit under Section 12.

• ✓ 1. The Gharial (Gavialis gangeticus) is a crocodilian listed in Schedule I, Part C (Reptiles).
• ✓ 2. The Indian wild ass (Equus hemionus) is listed in Schedule I, Part A (Mammals), under wild asses.
• ✓ 3. The wild water buffalo (Bubalus arnee) is listed in Schedule I, Part A (Mammals), under wild cattle.
• • Since then The Wildlife (Protection) Amendment Act, 2022 cut the schedules from six to four and rewrote Section 9 to ban hunting of Schedule I and II animals. All three animals remain in Schedule I, so the answer is unchanged.

Remember · Schedule I species get absolute protection: hunting is allowed only under Section 11 (animal dangerous or beyond recovery) or Section 12 (special permits, such as research). Gharial, wild buffalo and wild ass are all Schedule I.

Question and answer: UPSC's official GS Paper I (2017, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink · Report an error

Answer: (b) Chambal River

The Chambal River is the best place to see gharials in the wild. A 600 km stretch of it is the National Chambal Sanctuary, set up in 1978 mainly to protect the gharial, and it has the world's largest population of the species.

• ✓ (b) The National Chambal Sanctuary, on the Chambal, was created in 1978 under the Wildlife (Protection) Act, 1972 for the conservation and management of the gharial (Gavialis gangeticus).
• ✗ (a) Bhitarkanika is a coastal mangrove area of Odisha, not a river stretch protected for gharials.
• ✗ (c) Pulicat is a brackish-water lagoon shared by Andhra Pradesh and Tamil Nadu, better known as a bird-watching site than for gharials.

Remember · Gharial (Gavialis gangeticus): the National Chambal Sanctuary, a 600 km stretch of the Chambal River protected since 1978, has the world's largest wild population.

Question and answer: UPSC's official GS Paper I (2017, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink · Report an error

Answer: (b) Maintenance of Tiger Reserves

M-STrIPES is the Monitoring System for Tigers: Intensive Protection and Ecological Status, a technology platform of the National Tiger Conservation Authority. It is used to assist patrolling, assess ecological status and reduce human-wildlife conflict in and around tiger reserves.

• ✓ (b) NTCA describes it as a platform that helps manage tiger reserves through effective patrolling, ecological assessment and conflict mitigation. That is the maintenance of Tiger Reserves.
• ✗ (a) M-STrIPES monitors tigers in their reserves. It is not a captive-breeding programme.
• ✗ (c) India's indigenous satellite navigation system is the ISRO-run Indian Regional Navigation Satellite System (IRNSS), also called NavIC.
• ✗ (d) It has nothing to do with highway security; it works in and around tiger reserves.

Remember · M-STrIPES = Monitoring System for Tigers: Intensive Protection and Ecological Status, NTCA's technology platform for patrolling and monitoring in tiger reserves.

Question and answer: UPSC's official GS Paper I (2017, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink · Report an error

Answer: (a) It enjoys the same level of protection as the tiger.

Schedule I of the Wild Life (Protection) Act, 1972 gives a species the highest degree of protection, the same level as the tiger. Listing says nothing about the species being extinct in the wild or being confined to one region.

• ✓ (a) Tiger and other rare and endangered species are in Schedule I, which gives the highest degree of protection. A tortoise placed in the same Schedule gets that same top-level protection.
• ✗ (b) Schedule I is a legal category of protection for rare and endangered species that still live in the wild. It is not a statement that a species has disappeared from the wild or that extinction cannot be stopped.
• ✗ (c) Being endemic to one region is not the test for Schedule I. The Schedule lists rare and endangered species from many parts of the country, and the protection is the same wherever they live.
• ✗ (d) Both (b) and (c) are wrong, so (d) fails.

Remember · Schedule I of the Wild Life (Protection) Act, 1972 = highest legal protection, the same tier as the tiger. It does not mean 'extinct in the wild' or 'endemic'.

Question and answer: UPSC's official GS Paper I (2017, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). Permalink · Report an error