What biodiversity means, and why India is called mega-diverse

Biodiversity is the variety of life at three levels: genes within a species, species themselves, and ecosystems such as forests, grasslands, wetlands and coral reefs. A forest with many tree species, varied soil life and a range of pollinators is more biodiverse than a single-species plantation, even if both look green from a distance. Genetic diversity matters too, because it gives crops, livestock and wild species a better chance of coping with disease, drought and changing temperatures.

India is counted among the world's megadiverse countries. It covers about 2.4 per cent of the world's land area but, according to standard textbook and government summaries, accounts for roughly 7 to 8 per cent of recorded species. Its range of climates helps explain this: the Himalayas, the Western Ghats, the Thar desert, the Deccan plateau, the north-eastern hills and a long coastline create very different habitats within one country.

Four biodiversity hotspots are usually listed for India: the Himalayas, the Indo-Burma region, the Western Ghats and Sundaland, the last represented by the Nicobar Islands. A hotspot, in the sense used by Conservation International, is a region with exceptional numbers of species found nowhere else that has also lost much of its original habitat. Hotspot status is therefore a warning as well as a distinction.

For civil studies, the point is practical, not only scientific. Biodiversity supports pollination, soil fertility, fisheries, timber, medicines and water regulation. Losing it can raise food and health costs and make farming and coastal life more fragile. Conservation policy therefore sits between environment, agriculture, health, livelihoods and industry, and every choice involves trade-offs that must be argued in public, not assumed away. A useful habit is to ask, for any project or policy, which species and which people gain, which lose, and over what time period the loss becomes irreversible.