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Which of the following statements about biodiversity hotspots are CORRECT?
A. Hotspots are areas with extremely high species richness and endemism.
B. They cover about 2.5% of Earth's land but contain more than 50% of all endemic plant species.
C. India has no biodiversity hotspot.
D. The Western Ghats is an example of a biodiversity hotspot in India.
Options
1
A and B only
2
A, B and D only
3
C and D only
4
B and C only
Correct Answer
A, B and D only
Solution
1

A: High species richness + endemism = TRUE

B: ~2.5% land, >50% endemic plants = TRUE

C: India has no hotspot = FALSE (India has 4!)

2

D: Western Ghats is a hotspot = TRUE

Answer: A, B and D only

India has 4 hotspots: Western Ghats, E. Himalayas, Indo-Burma, Sundaland
C is FALSE
Theory: Biodiversity
1. Biodiversity Hotspots

Norman Myers introduced hotspot concept (1988, updated 2000). Criteria: (1) At least 1500 endemic vascular plant species (>0.5% world total). (2) Lost >70% original habitat. Currently 36 hotspots globally. Cover only ~2.5% of Earth land but contain >50% endemic plant species and >77% endemic vertebrates. India's 4 hotspots: Western Ghats + Sri Lanka, Eastern Himalayas, Indo-Burma, Sundaland (includes Nicobar Islands).

2. Levels of Biodiversity

Genetic diversity: variation within species (e.g., Rauwolfia vomitoria populations vary in reserpine potency). Species diversity: richness (number) + evenness (relative abundance). Shannon index H = -sum(pi ln pi). Ecosystem diversity: variety of habitats, biomes. Alpha diversity: within habitat. Beta diversity: between habitats. Gamma diversity: regional scale (alpha + beta). Tropical forests highest species richness per unit area.

3. Species-Area Relationship

S = CA^z (log S = log C + z log A). S = species richness, A = area, z = slope (0.1-0.2 for small areas on same continent; 0.6-1.2 for islands). Larger area = more species. Predicts species loss from habitat reduction. Example: 90% habitat loss with z=0.3 loses ~50% species. Basis for why large reserves are better than small fragmented ones.

4. Causes of Biodiversity Loss (HIPPCO)

Habitat destruction (number 1 cause), Invasive species (cane toad in Australia, Nile perch in Lake Victoria, water hyacinth), Pollution (DDT biomagnification, plastics), Population/overexploitation (poaching, overfishing), Climate change (coral bleaching, range shifts), Over-exploitation. Current extinction rate 1000-10,000x background rate = 6th mass extinction. Recent extinctions: Dodo (1681), passenger pigeon (1914), thylacine.

5. In-Situ Conservation

Conservation in natural habitat = best approach. Protected areas: National Parks (no human activity), Wildlife Sanctuaries (limited human use), Biosphere Reserves (core + buffer + transition). India: 106 National Parks, 567 Wildlife Sanctuaries, 18 Biosphere Reserves. Project Tiger (1973): tiger numbers 1800 (1973) to 3167 (2022). Project Elephant (1992). Sacred groves: community-protected forest patches (Orans in Rajasthan, Dev vans in HP).

6. Ex-Situ Conservation

Conservation outside natural habitat. Zoos, botanical gardens, gene banks, seed banks, cryopreservation. Svalbard Global Seed Vault (Norway): 1.3 million samples. National Bureau of Plant Genetic Resources (NBPGR), New Delhi: Indian seed bank. Cryopreservation: -196 degrees C liquid nitrogen. DNA banks. Limitation: cannot maintain ecological interactions, expensive, selective.

7. Ecosystem Services

Provisioning: food, medicine, timber, water. Regulating: climate, flood control, pollination (1/3 of human food depends on pollinators), pest control. Cultural: recreation, ecotourism, spiritual. Supporting: nutrient cycling, soil formation, photosynthesis. Value: ~$33-125 trillion/year (more than global GDP). 25% pharmaceuticals from plants. 80% developing world people use traditional plant medicine.

8. International Conservation Conventions

CBD (1992, Rio): 3 goals: conservation, sustainable use, benefit-sharing. Nagoya Protocol (2010): access and benefit-sharing. CITES (1975): controls wildlife trade. Appendix I: banned trade (tigers, rhinos). Appendix II: regulated. Ramsar (1971): wetlands. India has 75 Ramsar sites. UNESCO World Heritage: India has 40 sites. IUCN Red List categories: EX, EW, CR, EN, VU, NT, LC, DD.

Frequently Asked Questions
1. What are India's 4 biodiversity hotspots? ⌄
(1) Western Ghats + Sri Lanka: ~5000 endemic flowering plants, 139 endemic amphibians, lion-tailed macaque, Nilgiri tahr. (2) Eastern Himalayas: NE India + Bhutan + Nepal. Rich in orchids, red panda, snow leopard. (3) Indo-Burma: NE India (Mizoram, Manipur). Freshwater biodiversity rich. (4) Sundaland: Nicobar Islands of India. Each faces severe habitat loss from agriculture, urbanisation, infrastructure.
2. Why do hotspots cover only 2.5% of land but have over 50% of endemic plants? ⌄
Hotspots are biologically exceptional areas: diverse climate (many tropical/subtropical), complex terrain (mountains, coastlines), long evolutionary history without glaciation, high habitat heterogeneity creating many niches. These conditions drive speciation and allow many species to evolve in isolation, creating high endemism. They also happen to be in human-accessible, developable regions, so they face high threat - which is why they qualify as 'hotspots' (high diversity + high threat).
3. What is the difference between endemic and native species? ⌄
Native species: occurs naturally in a region (but may also occur elsewhere). Endemic species: ONLY found in that specific region - nowhere else in the world. Example: Indian tiger is native to India but not endemic (found in other Asian countries too). Purple frog (Nasikabatrachus sahyadrensis) is endemic to Western Ghats - found ONLY there. Endemism is caused by: geographic isolation (islands, mountains), specialised habitat requirements, limited dispersal ability. High endemism = high extinction risk if that region is destroyed.
4. What is in-situ vs ex-situ conservation? ⌄
In-situ: protecting species in their natural habitat. National Parks, Wildlife Sanctuaries, Biosphere Reserves. Advantages: maintains ecological interactions, evolutionary processes continue, cost-effective for many species. Ex-situ: conservation outside natural habitat. Zoos, botanical gardens, seed banks, cryopreservation. Advantages: can save critically endangered species, accessible for research, insurance against habitat loss. Limitations: cannot maintain all ecological interactions, expensive, space-limited. Best strategy: in-situ first, ex-situ as backup.
5. What is the IUCN Red List? ⌄
IUCN (International Union for Conservation of Nature) Red List: global database of conservation status of species. >150,000 species assessed; >42,000 threatened (as of 2023). Categories from most to least threatened: Extinct (EX), Extinct in Wild (EW), Critically Endangered (CR), Endangered (EN), Vulnerable (VU), Near Threatened (NT), Least Concern (LC), Data Deficient (DD), Not Evaluated (NE). India examples: CR = great Indian bustard, Gangetic dolphin. EN = tiger, Asian elephant. VU = lion, snow leopard.
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