Biodiversity Part 2: Hotspot Concept, Global Distribution, and India Mega-Diversity

Background and Historical Context

The hotspot framework drives global conservation prioritisation, channels donor funding, and shapes national biodiversity-action plans including India's. Approximately USD 4 billion in international conservation finance has been directed at hotspot regions since 1990 through the Critical Ecosystem Partnership Fund and bilateral programmes. UPSC Prelims has tested the hotspot concept directly in 2009, 2010, and 2011; the framework also anchors GS-III Mains questions on biodiversity conservation policy and disaster geography in fragile ecosystems.

What is the significance of the hotspot framework for India? India's four hotspots together cover roughly 18 per cent of the country's land area but host the majority of India's endemic species: approximately 4,950 endemic plants and 1,500 endemic vertebrates. The Western Ghats alone harbour 325 endemic vertebrates and 3,049 endemic plants; the Eastern Himalaya supports 3,500 endemic plants. The framework also defines India's policy spotlight: the National Biodiversity Action Plan and the CAMPA-funded compensatory afforestation prioritise hotspot-region protection.

The Kunming-Montreal Global Biodiversity Framework adopted at CBD COP-15 in December 2022 sets the 30-by-30 target requiring 30 per cent of land and sea protected by 2030. India's hotspot regions are the natural priority zones for meeting this target. The Critical Ecosystem Partnership Fund (CEPF) coordinated by Conservation International disbursed approximately USD 280 million across 24 hotspot regions in the 2020-2030 phase, with Western Ghats and Indo-Burma both receiving allocations. The Forest Conservation (Amendment) Act 2023 debate centres on hotspot-region exemptions for strategic infrastructure within 100 kilometres of international borders, directly affecting the Himalaya and Indo-Burma hotspots.

Origin of the Hotspot Concept: Norman Myers 1988

The 1988 paper in The Environmentalist and its conceptual breakthrough

Norman Myers, a British biogeographer, published the foundational hotspot paper Threatened biotas: Hot-spots in tropical forests in the journal The Environmentalist in 1988. The paper identified 10 tropical-forest hotspots harbouring 27 per cent of endemic plant species on just 0.2 per cent of Earth's land surface. Its diagnosis was that thinly spread conservation finance would yield far greater returns if concentrated at these few exceptional regions.

Myers extended the framework in 1990 to 18 hotspots and worked with Conservation International from 1996 to formalise the criteria. The 2000 reassessment in Nature by Myers, Mittermeier and colleagues established the canonical 25-hotspot list, later expanded to 34 in 2005 and to 36 by 2022.

Each expansion reflected better species inventories. The 2005 review added the Mountains of Central Asia, the Eastern Afromontane region, and the Maputaland-Pondoland-Albany. The Forests of East Australia joined in 2011 and the North American Coastal Plain in 2016, bringing the total to 36. Every new designation requires evidence that both thresholds are met simultaneously through fresh inventories and remote-sensing habitat-loss measurements.

• 1988 paper: 10 tropical-forest hotspots identified; 27 per cent endemic plants on 0.2 per cent of land.
• 1990 expansion: 18 hotspots; broadened beyond tropical forests.
• 1999-2000: Myers and Mittermeier co-authored Nature paper formalising 25-hotspot list.
• 2005 reassessment: Conservation International expanded to 34 hotspots.

Conservation International Criteria: 1,500 Endemic Plants and 70 Per Cent Loss

Two strict criteria: endemism threshold and habitat-loss threshold

Conservation International operationalises the hotspot designation through two strict thresholds applied simultaneously. A candidate region must demonstrate sufficient endemic-species concentration AND sufficient habitat loss; failing either disqualifies the region. The design ensures funding reaches regions where both biodiversity stakes and immediate threat are highest.

• Endemism threshold: The region must host at least 1,500 species of vascular plants as endemics, representing approximately 0.5 per cent of the global vascular plant total. Endemism is calculated at the region level, not at sub-region level.
• Habitat loss threshold: The region must have lost at least 70 per cent of its original primary vegetation. The threshold uses primary vegetation extent, not total forest cover, to capture genuine ecological-state loss.
• Species richness vs endemism: Hotspots are designated by endemism not raw richness; a high-richness region with low endemism does not qualify because its species exist elsewhere globally.
• Threat perception: The 70 per cent loss requirement encodes threat directly; regions still intact do not qualify regardless of endemism level.

Prelims 2011 tested exactly which criteria contributed to the Western Ghats-Sri Lanka and Indo-Burma hotspot designations. The three correct criteria are species richness, endemism, and threat perception; vegetation density, ethno-botanical importance, and warm-humid adaptation are NOT designation criteria.

The dual-criteria design has practical consequences for conservation finance. Funding agencies including the Critical Ecosystem Partnership Fund, the Global Environment Facility, and bilateral donors prioritise designated hotspot regions for ecosystem-based adaptation grants, livelihood funds, and protected-area expansion.

Regions adjacent to hotspots that remain largely intact fail the habitat-loss threshold and receive less concentrated attention under separate wilderness-area programmes. The design creates a paradox: by codifying habitat loss as a criterion, the framework rewards regions where conservation is already failing, leaving intact biodiverse regions outside the funding spotlight.

Global Distribution: 36 Hotspots Across Tropical and Temperate Regions

The 36 hotspots and their geographic concentration

The 36 hotspots are distributed unevenly across the globe. Tropical regions dominate the list: tropical Africa, Asia, and the Americas together host roughly 24 of the 36. Temperate hotspots include the California Floristic Province, the Mediterranean Basin, the Mountains of Central Asia, the Caucasus, Japan, and the Forests of East Australia. The misconception that hotspots are tropical-only is incorrect, a point tested directly by Prelims 2010.

India's Four Biodiversity Hotspots: Overview

Himalaya, Indo-Burma, Western Ghats and Sri Lanka, Sundaland

India hosts portions of four global hotspots. The terminology matters: Conservation International's 36-hotspot list uses these exact names, and Prelims 2010 tested directly whether the listing "Eastern Himalayas, Western Himalayas, Western Ghats, and Andaman and Nicobar Islands" is correct. It is NOT; the correct enumeration uses the four region names below.

• Himalaya hotspot: Includes the Eastern Himalaya (Sikkim, Arunachal Pradesh, north Bhutan, north Myanmar, south Tibet) and the Western Himalaya. Not split as two separate hotspots in the Conservation International list. Approximately 3,500 endemic plants and 1,500 endemic vertebrates.
• Indo-Burma hotspot: Covers north-east India (Assam, Manipur, Mizoram, Tripura, Nagaland, parts of Meghalaya), Myanmar, Bhutan east, southern China, Thailand, Vietnam, Cambodia, Laos. Approximately 7,000 endemic plants overall.
• Western Ghats and Sri Lanka hotspot: Combined unit covering the Indian Western Ghats and Sri Lankan wet zone. Approximately 3,049 endemic plants and 325 endemic vertebrates in the Indian Western Ghats alone.
• Sundaland hotspot: Covers western Indonesia, Malaysian Peninsula, Borneo, Sumatra, Java, and the Nicobar Islands as the Indian component. Approximately 15,000 endemic plants overall; Nicobar contributes approximately 200 endemic species.

These four units are not equal in extent or threat. The Himalaya and Indo-Burma hotspots are vast trans-national belts; the Western Ghats and Sri Lanka unit is a narrow but exceptionally endemic strip; the Indian share of Sundaland is confined to the Nicobar Islands. Each combines distinct climatic and topographic drivers of endemism with distinct conservation pressures.

India as a Mega-Diverse Country: 17-Country Club Membership

Mega-diverse country criteria and India's qualification

Mega-diverse country status is distinct from hotspot designation. The classification, identified by Conservation International, recognises 17 countries that collectively host most of Earth's species. The criteria require at least 5,000 endemic plant species and marine ecosystems within national borders. India qualifies on both counts: roughly 4,950 endemic plants (included by scientific consensus) plus marine ecosystems along its 7,500-kilometre coastline and the Andaman and Nicobar Islands.

Distinguishing features of mega-diverse versus hotspot designation: mega-diverse status applies at the country level and rewards total biological diversity; hotspot designation applies at the region level and rewards endemism combined with imminent threat. A mega-diverse country need not contain any hotspots, and a hotspot region need not lie within a mega-diverse country. India is unusual in being both, reflecting its exceptional climatic and topographic range.

India's specific qualifying features: marine ecosystems and endemic-plant near-threshold

India's mega-diverse qualification rests on three concrete features. The endemic-plant count of roughly 4,950 sits just below the 5,000 threshold; India's inclusion reflects scientific consensus, since the count understates true endemism while many cryptic species and recent taxonomic revisions remain unpublished.

The marine criterion is met through a 7,500-kilometre coastline and the Andaman and Nicobar archipelago, which hosts coral reef ecosystems rich in endemic fauna. The third feature is biogeographic breadth: India spans cold-desert Trans-Himalaya through tropical-rainforest Western Ghats to coral-reef islands, a range no other mega-diverse country except Indonesia matches.

The mega-diverse club shapes India's diplomatic position in global biodiversity negotiations. India co-chaired the Like-Minded Megadiverse Countries (LMMC) group from its 2002 Cancun founding; the group includes Brazil, China, Colombia, Indonesia, and 13 other countries that together negotiate as a bloc on access-and-benefit-sharing rules. India's leadership of the LMMC was central to the Nagoya Protocol negotiations in 2010 and continues to shape the implementation guidelines for the Kunming-Montreal framework's benefit-sharing provisions.

Kunming-Montreal Framework, CEPF, and the Indian Policy Horizon

30-by-30 target, CEPF funding, and India's hotspot policy stance

The Kunming-Montreal Global Biodiversity Framework adopted at CBD COP-15 in December 2022 sets four long-term Goals and 23 Targets. Target 3, the headline 30-by-30 commitment, requires that 30 per cent of terrestrial, inland water, coastal, and marine areas come under effective conservation by 2030. India's hotspot regions are the natural priority zones for delivering this target because they combine high endemism with existing institutional infrastructure (national parks, wildlife sanctuaries, biosphere reserves).

The Critical Ecosystem Partnership Fund (CEPF), coordinated by Conservation International with the Global Environment Facility, the European Union, the World Bank, and other partners, has disbursed roughly USD 280 million across 24 hotspots in its 2020-2030 phase. Western Ghats and Indo-Burma both receive Indian-relevant allocations through partner organisations such as the Centre for Wildlife Studies and Aaranyak.

Sources and Further Reading

• NCERT Class 11 India: Physical Environment, Chapter 5 – Natural Vegetation
• Wikipedia – Biodiversity hotspot
• Wikipedia – Norman Myers
• Wikipedia – Conservation International
• Wikipedia – Critical Ecosystem Partnership Fund
• Wikipedia – Biodiversity of India
• Wikipedia – Megadiverse countries
• Wikipedia – Endemism
• Wikipedia – Western Ghats
• Wikipedia – Indo-Burma
• Wikipedia – Convention on Biological Diversity