UPSC Previous Year Question | Prelims GS | 2017

Due to some reasons, if there is a huge fall in the population of species of butterflies, what could be its likely consequence/consequences? 1. Pollination of some plants could be adversely affected. 2. There could be a drastic increase in the fungal infections of some cultivated plants. 3. It could lead to a fall in the population of some species of wasps, spiders and birds. Select the correct answer using the code given below:

  1. 1 only
  2. 2 and 3 only
  3. 1 and 3 only
  4. 1, 2 and 3

Answer

Correct Answer

1 and 3 only

Explanation

Butterflies act as pollinators, so their decline would adversely affect pollination (statement 1 correct). They are prey for wasps, spiders, and birds, so a fall in butterfly population would reduce these predator populations too (statement 3 correct). There's no established causal link between butterfly decline and fungal infections in plants (statement 2 incorrect).

Topics: butterfly population decline, ecosystem and food chains, environment and ecology, geography