Which of the following examples represents species diversity?

The correct answer is Option (3) → Greater amphibian species diversity in the Western Ghats compared to the Eastern Ghats

NCERT describes biodiversity at three important levels. Genetic diversity is variation within one species. Species diversity is the variety of species in an area. Ecological diversity is the variety of ecosystems in a region. NCERT gives one example for each.

Option (1) Different concentrations of reserpine in Rauwolfia vomitoria — Incorrect. Variation in the potency and concentration of reserpine in Rauwolfia vomitoria from different Himalayan ranges is variation within a single species, that is, genetic diversity.

Option (2) 50,000 genetically different strains of rice in India — Incorrect. The many genetically different strains of rice in India are also variation within one species, so this is genetic diversity.

Option (3) Greater amphibian species diversity in the Western Ghats compared to the Eastern Ghats — Correct. The Western Ghats have more amphibian species than the Eastern Ghats. This compares the number of species in two regions, which is species diversity.

Option (4) The presence of deserts, rain forests, and coral reefs in India — Incorrect. Deserts, rain forests and coral reefs are different ecosystems, so their presence in India shows ecological diversity.

NCERT Extract:
Biodiversity – “… (i) Genetic diversity : A single species might show high diversity at the genetic level over its distributional range. The genetic variation shown by the medicinal plant Rauwolfia vomitoria growing in different Himalayan ranges might be in terms of the potency and concentration of the active chemical (reserpine) that the plant produces. India has more than 50,000 genetically different strains of rice, and 1,000 varieties of mango. (ii) Species diversity : The diversity at the species level, for example, the Western Ghats have a greater amphibian species diversity than the Eastern Ghats. (iii) Ecological diversity : At the ecosystem level, India, for instance, with its deserts, rain forests, mangroves, coral reefs, wetlands, estuaries, and alpine meadows has a greater ecosystem diversity than a Scandinavian country like Norway.”