Minimalist IAS
Environment & ecology

Prelims · Environment & ecology · 27 questions

Ecology & ecosystems

Every UPSC Prelims question on this topic, 2016–2026, newest first. Tap an option to check yourself; the answer and explanation open below it.

Ecology & ecosystems questions per year: 2016: 0, 2017: 1, 2018: 0, 2019: 0, 2020: 0, 2021: 7, 2022: 3, 2023: 0, 2024: 2, 2025: 1, 2026: 1 Asked in 6 of 11 years · most in 2021 (7)

UPSC syllabus: “General issues on Environmental ecology, Bio-diversity and Climate Change - that do not require subject specialization.” See the full syllabus →

Consider the following statements:

  1. 1.Some species of turtles are herbivores.
  2. 2.Some species of fish are herbivores.
  3. 3.Some species of marine mammals are herbivores.
  4. 4.Some species of snakes are viviparous.

Which of the statements given above are correct?

Answer & explanation

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.

Sources

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 ·

The same topic in Mains