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 :
- A.1 only
- B.2 and 3 only
- C.1 and 3 only
- D.1, 2 and 3
Correct answer
Explanation
The correct answer is C, 1 and 3 only. Butterflies are pollinators and also food for many animals, so their decline would hurt pollination and their predators; it has no direct link with fungal diseases of crops.
Adult butterflies feed on nectar and carry pollen from flower to flower, so many wild plants and some crops depend partly on them for pollination. Their eggs, caterpillars and adults are eaten by birds, spiders, lizards and bats, and some wasps lay their eggs inside caterpillars; these parasitoid wasps cannot complete their life cycle without them. A sharp fall in butterflies would therefore ripple up the food web. Because they react quickly to changes in habitat and climate, butterflies are also used as indicator species of the health of an ecosystem.
Statement 2 is wrong: butterflies do not control plant fungi, so their loss would not cause a drastic rise in fungal infections.
So A, B and D are wrong.
Exam tip: butterflies = pollinators + prey + indicator species; the parasitoid wasp depends on caterpillars.
Practice Questions
View allConsider the following :
1. Battery storage
2. Biomass generators
3. Fuel cells
4. Rooftop solar photovoltaic units
How many of the above are considered "Distributed Energy Resources"?
- A.Only one
- B.Only two
- C.Only three
- D.All four
Show answer
Battery storage, biomass generators, fuel cells and rooftop solar units are all small, local sources that generate or store power close to where it is used, which is what Distributed Energy Resources are.
Read the full explanation →Consider the following statements :
1. Lions do not have a particular breeding season.
2. Unlike most other big cats, cheetahs do not roar.
3. Unlike male lions, male leopards do not proclaim their territory by scent marking.
Which of the statements given above are correct ?
- A.1 and 2 only
- B.2 and 3 only
- C.1 and 3 only
- D.1, 2 and 3
Show answer
Lions breed at any time of year and cheetahs cannot roar, but male leopards do mark their territory with scent.
Read the full explanation →Which one of the following National Parks lies completely in the temperate alpine zone?
- A.Manas National Park
- B.Namdapha National Park
- C.Neora Valley National Park
- D.Valley of Flowers National Park
Show answer
Set high in the Garhwal Himalaya of Uttarakhand, roughly between 3,200 and 6,600 metres, it lies wholly in the temperate alpine zone.
Read the full explanation →Consider the following kinds of organisms:
1. Copepods
2. Cyanobacteria
3. Diatoms
4. Foraminifera
Which of the above are primary producers in the food chains of oceans?
- A.1 and 2
- B.2 and 3
- C.3 and 4
- D.1 and 4
Show answer
Cyanobacteria and diatoms carry out photosynthesis, so they are phytoplankton, the primary producers at the base of ocean food chains.
Read the full explanation →Consider the following statements :
Statement-I : Carbon markets are likely to be one of the most widespread tools in the fight against climate change.
Statement-II : Carbon markets transfer resources from the private sector to the State.
Which one of the following is correct in respect of the above statements?
- A.Both Statement-I and Statement-II are correct and Statement-II is the correct explanation for Statement-I
- B.Both Statement-I and Statement-II are correct and Statement-II is not the correct explanation for Statement-I
- C.Statement-I is correct but Statement-II is incorrect
- D.Statement-I is incorrect but Statement-II is correct
Show answer
Carbon markets are a leading climate tool, but they work by moving money between emitters and those who cut emissions, not from the private sector to the State.
Read the full explanation →