Prelims GS I · 245 questions · 2011–2026
Environment & ecology: every Prelims question, by topic
UPSC syllabus: “General issues on Environmental ecology, Bio-diversity and Climate Change - that do not require subject specialization.” Below, the topics inside it — most asked first — and how often each came up year by year.
Environment & ecology in Prelims 2024: 14 questions
All years →- Q16 · Ecology & ecosystemsOne of the following regions has the world's largest tropical peatland, which holds about three years worth of global carbon emissions from fossil fuels; and the possible destruction of which can exer…
- Q17 · Pollution & wasteWith reference to perfluoroalkyl and polyfluoroalkyl substances (PFAS) that are used in making many consumer products, consider the following statements: PFAS are found to be widespread in drinking wa…
- Q18 · Biodiversity, plants & animalsConsider the following: Carabid beetles Centipedes Flies Termites Wasps…
- Q20 · Environmental laws, bodies & conventionsConsider the following statements: The Indian Flying Fox is placed under the "vermin" category in the Wild Life (Protection) Act, 1972. The Indian Flying Fox feeds on the blood of other animals.…
- Q21 · Biodiversity, plants & animalsThe organisms "Cicada, Froghopper and Pond skater" are:…
- Q22 · Pollution & wasteConsider the following statements: Many chewing gums found in the market are considered a source of environmental pollution. Many chewing gums contain plastic as gum base.…
- Q23 · Biodiversity, plants & animalsConsider the following pairs: Brazil — Indri Indonesia — Elk Madagascar — Bonobo…
- Q25 · Biodiversity, plants & animalsConsider the following statements: Lions do not have a particular breeding season. Unlike most other big cats, cheetahs do not roar. Unlike male lions, male leopards do not proclaim their territory by…
- Q28 · Ecology & ecosystemsWhich one of the following shows a unique relationship with an insect that has coevolved with it and that is the only insect that can pollinate this tree?…
- Q29 · Biodiversity, plants & animalsConsider the following: Butterflies Fish Frogs…
- Q30 · Biodiversity, plants & animalsConsider the following: Cashew Papaya Red sanders…
- Q39 · Pollution & waste"Membrane Bioreactors" are often discussed in the context of:…
- Q90 · Pollution & wasteAccording to the Environmental Protection Agency (EPA), which one of the following is the largest source of sulphur dioxide emissions?…
- Q96 · Climate change & agreementsConsider the following statements: The European Parliament approved The Net-Zero Industry Act recently. The European Union intends to achieve carbon neutrality by 2040 and therefore aims to develop al…
Environment & ecology in UPSC Prelims at a glance
UPSC has asked 245 questions on Environment & ecology in GS Paper I from 2011 to 2026 — about 15 a year, the most in 2014 (23). The most-asked topic is Biodiversity, plants & animals (62 questions).
| Year | 2011 | 2012 | 2013 | 2014 | 2015 | 2016 | 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 | 2026 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Questions | 16 | 18 | 17 | 23 | 15 | 17 | 13 | 11 | 18 | 12 | 20 | 16 | 13 | 14 | 13 | 9 |
Counted from UPSC's own papers in the Vault, each question under its main subject · updated 8 Nov 2026.
- Biodiversity, plants & animals62 questions · asked in 15 of 16 years
- Pollution & waste43 questions · asked in 15 of 16 years
- Climate change & agreements40 questions · asked in 14 of 16 years
- Environmental laws, bodies & conventions40 questions · asked in 15 of 16 years
- Ecology & ecosystems33 questions · asked in 11 of 16 years
- Protected areas & conservation27 questions · asked in 13 of 16 years
Latest questions
- 2026 · Q21 · Climate change & agreementsConsider the following statements with reference to India's response to climate change: I. India's Long-Term Low Emission Development Strategy (LT-LEDS) is a crucial tool…
- 2026 · Q22 · Biodiversity, plants & animalsWith respect to the Western Hoolock Gibbons, which of the following statements is/are correct?…
- 2026 · Q23 · Ecology & ecosystemsWhich of the following best explain(s) the rationale for protecting mangrove ecosystems in the context of climate resilience?…
- 2026 · Q27 · Biodiversity, plants & animalsWhich of the following statements with regard to the arrival of Amur Falcons at Doyang Lake in Nagaland each year from Mongolia is/are correct?…
- 2026 · Q32 · Protected areas & conservationWith reference to Madhav National Park, which of the following statements is/are correct?…
The same ground in Mains
These official Mains syllabus lines cover Environment & ecology. Prelims facts become Mains arguments.
Environment & ecology PYQs as a PDF — free
All 48 PDFs →Every Environment & ecology question from 2011 to 2026, topic-wise, with answers and explanations — 120 pages. Free; sign up once.
Environment & ecology PYQs: quick answers
How many Environment & ecology questions has UPSC asked in Prelims from 2011 to 2026?
245 questions in GS Paper I — about 15 a year, the most in 2014 (23). Every one is on this page, under its topic, with UPSC's answer and an explanation.
Which Environment & ecology topic does UPSC ask most in Prelims?
Biodiversity, plants & animals: 62 questions between 2011 and 2026, asked in 15 of 16 years. The topics are listed above, most asked first, each with its year-by-year trend.
Are the answers UPSC's official answer keys?
From 2016, yes: every answer is from UPSC's final answer key (2016–2025); for 2011–2015, where UPSC published no key online, each answer is worked out from official sources and reviewed independently; for 2026 UPSC has so far published a provisional key, and those answers are labelled. Explanations cite official sources — NCERT and government pages first.
Can I download the Environment & ecology PYQs as a PDF?
Yes — a print-ready PDF of every Environment & ecology question with answers and explanations (120 pages, 2.4 MB), free after a one-time sign-up, from the Vault's downloads page.
Counted from UPSC's own papers in the Vault; answers are UPSC's keys.
