
UPSC Essentials brings to you its initiative of subject-wise quizzes. These quizzes are designed to help you revise some of the most important topics from the static part of the syllabus. Attempt today’s subject quiz on Environment and Geography to check your progress.
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1. The species is found only in a narrow strip of coastal dunes stretching across parts of Namibia and South Africa.
2. It is listed as critically endangered on the IUCN Red List.
3. One of the reasons for its population decline is diamond mining.
4. The species spends most of its life burrowed beneath the sand.
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Which one of the following conclusions based on the above statements is correct?
(a) There are four correct statements.
(b) There are three correct statements, that include statements 1 and 4.
(c) There are two correct statements, that include statement 3.
(d) There is no correct statement.
Relevance: Species in the news are a recurring theme in Environment and Ecology. UPSC frequently asks questions on the habitat, geographic distribution, conservation status (IUCN Red List), endemic species, and threats to wildlife, especially those highlighted in recent scientific studies or conservation reports.
Explanation
— The desert rain frog (Breviceps macrops), whose high-pitched defensive squeak turned it into one of the internet’s most-loved amphibians, has now been listed as Vulnerable on the International Union for Conservation of Nature (IUCN) Red List. Hence, statement 2 is not correct.
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— The desert rain frog is found nowhere else on Earth except a narrow strip of coastal sand dunes stretching across parts of Namibia and South Africa. The species spends most of its life burrowed beneath the sand, emerging mainly to feed and breathe. Hence, statements 1 and 4 are correct.
— According to the latest IUCN Red List assessment, the frog’s population is projected to decline by around 20 per cent over the next two decades, largely because its fragile habitat is under increasing pressure.
— Diamond mining, along with proposed energy developments, is shrinking and degrading the sand dunes the frog depends on for survival. Because the species occupies such a specialised habitat, it has very little room to adapt if that environment is destroyed. Hence, statement 3 is correct.
— Illegal wildlife trade has already affected several rare amphibian species around the world, prompting conservationists to remain cautious whenever an animal suddenly becomes an online celebrity.
Therefore, option (b) is the correct answer.
QUESTION 2
Consider the following statements:
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1. Every avian generation makes choices about which songs to continue singing, which to improve upon and which to drop altogether.
2. During their critical song-learning phase of development, young songbirds imitate the adult males in their group who are successful in courtship or have elaborately ornamented plumage.
Which one of the following is correct in respect of the above statements?
(a) Both Statement 1 and Statement 2 are correct and Statement 2 is the correct explanation for Statement 1.
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(b) Both Statement 1 and Statement 2 are correct and Statement 2 is not the correct explanation for Statement 1.
(c) Statement 1 is correct but Statement 2 is incorrect.
(d) Statement 1 is incorrect but Statement 2 is correct.
Relevance: Birdsong and animal behaviour are important from the perspective of Ecology and Environment, especially concepts such as animal communication, behavioural ecology, learning, adaptation, sexual selection, and cultural transmission in animals.
Explanation
— Like human language, birdsong is dynamic. Every avian generation makes choices about which songs to continue singing, which to improve upon and which to drop altogether. A single Bachman’s sparrow might learn only 48 of the songs used by its community, and for decades researchers have been trying to figure out how baby sparrows choose which songs to adopt. Hence, statement 1 is correct.
— During their critical song-learning phase of development, young songbirds imitate the adult males in their group who are successful in courtship or have elaborately ornamented plumage. Hence, statement 2 is correct.
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Why Statement 2 explains Statement 1: The generational “choices” indicated in Statement 1 are not intentional decisions, but rather result from juveniles selectively copying the songs of successful males. Songs associated with reproductively successful males are passed down to the next generation, whilst less successful song variants gradually disappear. Thus, selective imitation is the process driving the cultural evolution of birdsong indicated in Statement 1.
Therefore, option (a) is the correct answer.
QUESTION 3
With reference to the waterfalls and the associated countries, consider the following pairs:
1. Tugela Falls – Peru
2. Angel Falls – Venezuela
3. Yumbilla Falls – South Africa
How many of the pairs given above are correctly matched?
(a) Only one pair
(b) Only two pairs
(c) All three pairs
(d) None of the above pairs
Relevance: Major waterfalls of the world are an important topic under World Geography. UPSC can ask map-based questions on the location of waterfalls, rivers, mountain ranges, and associated countries.
Explanation
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— Angel Falls (Venezuela): At an impressive height of 979 metres (3,212 feet) and 150 metres (500 feet), Angel Falls holds the title of the world’s highest uninterrupted waterfall. Located in the heart of Canaima National Park, the waterfall plunges from the summit of Auyán-tepui, one of Venezuela’s iconic table-top mountains. Hence, pair 2 is correct.
— Tugela Falls (South Africa): Often at the centre of debates over the world’s tallest waterfall, Tugela Falls has a total drop of approximately 411 metres (1,350 feet). Located within the Drakensberg Mountains, it consists of a series of falls that tumble down sheer basalt cliffs. The surrounding hiking trails offer pleasing views of the landscape. Hence, pair 1 is not correct.
— Tres Hermanas Falls (Peru): Known as the “Three Sisters Falls,” this spectacular waterfall plunges from a height of around 914 metres (2,999 feet) through the dense cloud forests of Peru. Hidden deep within a remote national park, it remains one of the least-visited yet most impressive waterfalls in the world.
— Olo’upena Falls (United States): Dropping approximately 900 metres (2,953 feet), Olo’upena Falls cascades down one of the world’s tallest sea cliffs on the Hawaiian island of Molokai. Because of its inaccessible location, the waterfall is best viewed from the air or by boat.
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— Yumbilla Falls (Peru): With a height of about 896 metres (2,940 feet), Yumbilla Falls is among Peru’s greatest natural treasures. The waterfall descends through multiple tiers, surrounded by lush vegetation and is increasingly gaining recognition among adventure travellers. Hence, pair 3 is not correct.
Therefore, option (a) is the correct answer.
QUESTION 4
Which of the following factors triggers landslides?
1. Rock stability
2. Deforestation
3. Rainfall
4. Latitude
5. Drainage pattern
Select the correct answer using the codes given below:
(a) 1, 2 and 3
(b) 1 and 3 only
(c) 1, 2, 3, 4 and 5
(d) 2, 3 and 5 only
Relevance: Landslides are an important topic under Geography, Disaster Management, and Environment. UPSC can ask questions on the causes, triggering factors, vulnerability of the Himalayan and Western Ghats regions, and early warning systems, especially in the context of recent extreme rainfall events and landslide disasters.
Explanation
— The landslides in recent days in the Western Ghats and other parts of India have reignited discussions on the need for an early warning system for such events. Such systems already work effectively in many countries. Two well-publicised successful cases come from Switzerland, where separate instances from 2023 and 2025 saw hundreds of people evacuated from a hazardous area a few days before disaster struck.
— About 13% of India’s total landmass, covering about 0.42 million square km, is known to be prone to landslides, according to the National Disaster Management Authority. The risk is highest in the Himalayan region and along the Western Ghats.
— Recently, Professor Dericks Praise Shukla and his team at IIT Mandi have unveiled their own landslide early warning system, which is in the process of getting validated with ongoing events in the Himalayan region. Over the last year, their models were validated against about 80 actual landslides in the region. Since rainfall is one of the most common triggers, the team uses highly localised rainfall forecasts to model the probability of a landslide at these sites. Several other relevant factors like soil conditions, rock stability, extent of slope, and population density have to be fed into the model.
— Factors that trigger landslides include rainfall, rock stability, soil type and condition, seismic activity, erosion, and deforestation.
— Latitude and drainage patterns do not trigger landslides.
Therefore, option (a) is the correct answer.
QUESTION 5
Consider the following statements:
1. Hydrogen is a high-energy-density fuel in comparison to diesel.
2. Hydrogen trains require high maintenance in comparison to diesel trains.
3. India does not have a hydrogen storage and refuelling facility.
Which one of the following conclusions based on the above statements is correct?
(a) All three statements are correct.
(b) There are two correct statements, that include statement 1.
(c) There is only one correct statement.
(d) There is no correct statement.
Relevance: Hydrogen fuel-cell technology is an important topic under Science and Technology, Energy, and Environment. UPSC may ask conceptual questions on hydrogen production, storage, fuel-cell technology, energy density, and the National Green Hydrogen Mission.
Explanation
— The Jind-Sonipat hydrogen train will be powered by hydrogen fuel. The train will use a 1,200 KW hydrogen fuel cell propulsion system, which will generate power to operate the train. This hydrogen train is a converted version of a Diesel Electric Multiple Unit (DEMU) rake.
— Hydrogen is a high-energy-density fuel (120 MJ/Kg) in comparison to diesel (43 MJ/Kg), with low maintenance and a manageable Carbon footprint. In the proposed hybrid power system, the primary energy source is a Proton Exchange Membrane Fuel Cell (PEMFC) and the secondary energy source will be a battery bank to meet the average and peak power requirements. Hence, statement 1 is correct and statement 2 is not correct.
— According to the Ministry of Railways, hydrogen fuel cell technology generates electricity through a chemical reaction involving hydrogen. The process produces only water vapour as an emission, making it a cleaner alternative to conventional fossil fuel-based traction systems.
— To refuel India’s first hydrogen trainset, a hydrogen storage and refuelling facility has been set up at Haryana’s Jind. The facility has received the license from the Petroleum and Explosives Safety Organisation (PESO) for the storage and dispensing of compressed hydrogen gas. Hence, statement 3 is not correct.
Therefore, option (c) is the correct answer.
Previous Daily Subject-Wise-Quiz
Daily Subject-wise quiz — History, Culture, and Social Issues (Week 159)
Daily subject-wise quiz — Polity and Governance (Week 171)
Daily subject-wise quiz — Science and Technology (Week 171)
Daily subject-wise quiz — Economy (Week 171)
Daily subject-wise quiz — Environment and Geography (Week 170)
Daily subject-wise quiz – International Relations (Week 170)
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