Biodiversity is the variety of living organisms on the earth. It includes diversity within species or between species and of eco-systems. The earth’s biological resources are vital to humanity’s economic and social development. Globally, so far 1.75 million species have been identifi ed against the estimates ranging from 3 to 100 million. There is growing recognition that biodiversity is a global asset of tremendous values to present
and future generations. At the same time, the threat to species and ecosystems has never been as great as it is today, as a result of which species extinction caused by human activities continues at an alarming rate. This calls for global and national actions towards conservation of biodiversity.
India: A Treasure of Biodiversity
India is known for its rich heritage of biodiversity. In biological diversity parlance,India is one of the 17 mega-diverse countries in the world. With only 2.4% of theworld’s area, India accounts for 7-8% of the world’s recorded plant (about 45,000, of which approximately 15,000 are of known medicinal value) and animal species (about 91,000). India’s ten biogeographic zones possess an exemplary diversity of ecological
habitats like alpine forests, grasslands, wetlands, coastal and marine ecosystems, and desert ecosystems. India has four out of thirty four global biodiversity hotspots, which is an indicator of high degree of endemism (of species) in India. About 5,150 plant species and 1,837 animal species are endemic to India. India’s biodiversity includes wild relatives of agricultural crops and domesticated animals. India has 16 major types and 251 subtypes of forests. The large mosaic of distinct agro-ecosystems has contributed to
diverse cropping pattern and systems across the country.
Conservation of India’s Biodiversity:
A Progressive Framework Environment protection is enshrined in the Constitution of India [Article 48A and Article 51A (g)]. Wide-ranging policies,programmes and projects are in place, which directly or indirectly
serve to protect, conserve and sustainably use the country’s biological resources. These include the Forest (Conservation)Act, Wildlife (Protection) Act, Biological Diversity Act, National Green Tribunal Act, National Biodiversity Action Plan, National Forest Policy, National Wildlife Action Plan, National Forestry
Action Programme, National Environment Policy and National Action Plan on Climate Change.
India is committed to conservation of biodiversity. This is not only because of India’s international obligations as a signatory to the Convention on Biological Diversity, but because India believes that protecting our biodiversity is a critical national priority as it is linked to local livelihoods of millions of people
in the country. Sustainable use of our biodiversity, therefore,has both ecological and economic value. It is with this objective that India has enacted Biological Diversity Act, 2002 and set up a National Biodiversity Authority (NBA) in 2003 with an explicit mandate of promoting conservation of biological resources and associated knowledge as well as facilitating access
to them in a sustainable manner.
Fauna of India India has some of the world's most biodiverse regions. The political boundaries of India encompass a wide range of ecozones—desert, high mountains, highlands, tropical and temperate forests, swamplands, plains, grasslands, areas surrounding rivers, as well as island archipelago. It hosts 3 biodiversity hotspots: the Western Ghats, the Himalayas and the Indo-Burma region. These hotspots have numerous endemic species.
India, for the most part, lies within the Indomalaya ecozone, with the upper reaches of the Himalayas forming part of the Palearctic ecozone; the contours of 2000 to 2500m are considered to be the altitudinal boundary between the Indo-Malayan and Palearctic zones. India displays significant biodiversity. One of eighteen megadiverse countries, it is home to 7.6% of all mammalian, 12.6% of all avian, 6.2% of all reptilian, 4.4% of all amphibian, 11.7% of all fish, and 6.0% of all flowering plant species.
The region is also heavily influenced by summer monsoons that cause major seasonal changes in vegetation and habitat. India forms a large part of the Indomalayan biogeographical zone and many of the floral and faunal forms show Malayan affinities with only a few taxa being unique to the Indian region. The unique forms includes the snake family Uropeltidae found only in the Western Ghats and Sri Lanka. Fossil taxa from the Cretaceous show links to the Seychelles and Madagascar chain of islands.The Cretaceous fauna include reptiles, amphibians and fishes and an extant species demonstrating this phylogeographical link is the purple frog. The separation of India and Madagascar is traditionally estimated to have taken place about 88 million years ago. However, there are suggestions that the links to Madagascar and Africa were present even at the time when the Indian subcontinent met Eurasia. India has been suggested as a ship for the movement of several African taxa into Asia. These taxa include five frog families (including the Myobatrachidae), three caecilian families, a lacertid lizard and freshwater snails of the family Potamiopsidae. A fossil tooth of what is believed to be of from a lemur-like primate from the Bugti Hills of central Pakistan however has led to suggestions that the lemurs may have originated in Asia. These fossils are however from the Oligocene (30 million years ago) and have led to controversy. Lemur fossils from India in the past led to theories of a lost continent called Lemuria. This theory however was dismissed when continental drift and plate tectonics became well established.
India is home to several well-known large mammals, including the Asian elephant, Bengal tiger, Asiatic lion, leopard and Indian rhinoceros. Some of these animals are engrained in culture, often being associated with deities. These large mammals are important for wildlife tourism in India, and several national parks and wildlife sanctuaries cater to these needs. The popularity of these charismatic animals have helped greatly in conservation efforts in India. The tiger has been particularly important, and Project Tiger, started in 1972, was a major effort to conserve the tiger and its habitats. Project Elephant, though less known, started in 1992 and works for elephant protection. Most of India's rhinos today survive in the Kaziranga National Park. Some other well-known large Indian mammals are: ungulates such as the water buffalo, nilgai, gaur and several species of deer and antelope. Some members of the dog family such as the Indian wolf, Bengal fox, golden jackal and the dhole or wild dogs are also widely distributed. It is also home to the striped hyaena. Many smaller animals such as macaques, langurs and mongoose species are especially well known due to their ability to live close to or inside urban areas.
Biodiversity hotspots
The Western Ghats
The Western Ghats are a chain of hills that run along the western edge of peninsular India. Their proximity to the ocean and through orographic effect, they receive high rainfall. These regions have moist deciduous forest and rain forest. The region shows high species diversity as well as high levels of endemism. Nearly 77% of the amphibians and 62% of the reptile species found here are found nowhere else. The region shows biogeographical affinities to the Malayan region, and the Satpura hypothesis proposed by Sunder Lal Hora suggests that the hill chains of Central India may have once formed a connection with the forests of northeastern India and into the Indo-Malayan region. Hora used torrent stream fishes to support the theory, but it was also suggested to hold for birds. Later studies have suggested that Hora's original model species were a demonstration of convergent evolution rather than speciation by isolation.More recent phylogeographic studies have attempted to study the problem using molecular approaches.There are also differences in taxa which are dependent on time of divergence and geological history. Along with Sri Lanka this region also shows some fauna similarities with the Madagascan region especially in the reptiles and amphibians. Examples include the Sinophis snakes, the purple frog and Sri Lankan lizard genus Nessia which appears similar to the Madagascan genus Acontias. Numerous floral links to the Madagascan region also exist. An alternate hypothesis that these taxa may have originally evolved out-of-India has also been suggested.
Rhinoceros unicornis, Kaziranga
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