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Biodiversity
Amazing Diversity of Life
- Earth supports an extraordinary variety of organisms, such as:
- More than 20,000 species of ants
- Around 300,000 species of beetles
- About 28,000 species of fishes
- Nearly 20,000 species of orchids
- This diversity raises fundamental biological questions:
- Why are there so many species?
- Did such diversity always exist?
- How did it evolve?
- How important is biodiversity for biosphere stability?
- How do humans benefit from it?
15.1 Biodiversity – Concept
- Definition
- Biodiversity (biological diversity) refers to the variety of life forms at different levels of biological organization — from genes to ecosystems — along with their interactions.
Historical Note
- Term first coined by Walter G. Rosen (1985)
- Popularised by Edward O. Wilson
Biodiversity varies regionally depending on environmental conditions and species tolerance limits.
Levels of Biodiversity
Biodiversity exists at three hierarchical levels:
1. Genetic Diversity
- Variation in genes within a species.
- Examples
- Over 50,000 genetically distinct rice strains in India.
- Around 1,000 mango varieties in India.
- Rauwolfia vomitoria shows variation in reserpine content across Himalayan regions.
- Significance
- Enhances adaptability
- Increases survival under environmental change
2. Species Diversity
- Variety and richness of species in a given region.
- Key Concepts
- Species richness → Number of species per unit area
- Species evenness → Relative abundance of species
- Example
- Western Ghats have greater amphibian diversity than Eastern Ghats.
3. Ecological Diversity
- Variation at ecosystem and habitat levels.
- Example: India contains diverse ecosystems such as:
- Deserts
- Rainforests
- Mangroves
- Coral reefs
- Wetlands
- Estuaries
- Alpine meadows
- Components
- Alpha diversity → Within a habitat
- Beta diversity → Between habitats
- Gamma diversity → Across large geographical regions
How Many Species Exist on Earth?
- Recorded Species
- About 1.5 million species described globally
- Estimated Total
- Estimates range from 20–50 million
- Robert May estimated approximately 7 million species
- Taxonomic Distribution
- >70% of recorded species are animals
- >70% of animals are insects
- About 7 out of every 10 animals are insects
- Plants: Plants (including algae, fungi, bryophytes, gymnosperms, angiosperms) → ≤22%
- Fungi: Fungi species exceed the combined total of fishes, amphibians, reptiles, and mammals
Microbial Diversity
- Exact number unknown due to:
- Identification difficulty
- Morphological similarity
- If molecular methods are used, microbial diversity may reach millions.
Biodiversity in India
- Land Area Contribution
- India occupies only 2.4% of the world’s land area
- Species Contribution
- Accounts for 8.1% of global biodiversity
- Recorded Species
- ~45,000 plant species
- ~90,000 animal species
- Estimated Undiscovered Species
- >100,000 plant species
- >300,000 animal species
India is recognised as one of the 12 mega-diverse countries of the world.
Biogeographical Regions of India (not mentioned in NCERT)
- Trans-Himalayas
- Himalayas
- Desert
- Semi-arid
- Western Ghats
- Deccan Peninsula
- Gangetic Plain
- North-East India
- Marine Coasts
- Indian Islands
Endemic Species
- Species restricted to a specific region.
- Example: Western Ghats are rich in endemic amphibians.
Importance of Biodiversity
- Result of millions of years of evolution
- Provides ecosystem stability
- Supports food webs and nutrient cycles
- Maintains ecological balance
- Current concern:
- Present extinction rates may erase significant biodiversity within two centuries.
Challenges in Biodiversity Assessment
- Shortage of trained taxonomists
- Time-consuming identification process
- Many species may go extinct before discovery
Summary Points
- Biodiversity exists at genetic, species, and ecosystem levels
- >70% of species are animals; insects dominate
- India: 2.4% land but 8.1% global biodiversity
- Estimated global species ≈ 7 million (Robert May)
- India is a mega-diverse nation
- Conservation is urgent due to rapid species loss
Patterns of Biodiversity
- Biodiversity is not uniformly distributed across the globe.
- It follows certain predictable ecological patterns.
1. Latitudinal Gradients
- General Pattern
- Species diversity decreases from the equator toward the poles.
- Tropics (23.5°N to 23.5°S) harbour more species than temperate and polar regions.
- Examples
- Colombia (near equator) → ~1,400 bird species
- India (tropical region) → >1,200 bird species
- New York (41°N) → 105 bird species
- Greenland (71°N) → 56 bird species
- Amazon Rainforest – Highest Biodiversity on Earth
- ~40,000 plant species
- 3,000 fish species
- 1,300 bird species
- 427 mammal species
- 427 amphibian species
- 378 reptile species
- >125,000 invertebrates
- ~2 million insect species yet to be discovered
Why Are Tropics More Diverse?
- Evolutionary Time
- Tropical regions remained relatively undisturbed for millions of years (no repeated glaciations).
- Long evolutionary time allowed extensive speciation.
- Stable Environment
- Less seasonal variation
- Predictable climate
- Promotes niche specialization
- Higher Solar Energy
- Greater sunlight availability
- Higher primary productivity
- Supports complex food webs
- Leads to greater species diversity
Species-Area Relationships
- Observation
- Proposed by Alexander von Humboldt.
- Species richness increases with increasing explored area — but only up to a limit.
- Graph Pattern
- Rectangular hyperbola (normal scale)
- Straight line on logarithmic scale
- Mathematical Equation
- log S = log C + Z log A
- Where:
- S → Species richness
- A → Area
- Z → Slope (regression coefficient)
- C → Y-intercept
- Value of Z
- For small areas → 0.1 to 0.2
- For very large areas (continents) → 0.6 to 1.2
- Example: Frugivorous birds and mammals in tropical forests → Z ≈ 1.15
Key Concept
- Larger geographical areas show steeper slopes because:
- Habitat diversity increases
- Evolutionary processes operate at broader scales
- Greater environmental heterogeneity supports more species
Quick Revision Points
- Biodiversity highest in tropics, lowest near poles
- Amazon rainforest = global biodiversity hotspot
- Species richness increases with area
- Z value higher for large continental scales
- Latitudinal gradient + species–area relationship explain global diversity patterns
Importance of Species Diversity
Does Species Number Matter?
- Yes. Species diversity strongly influences ecosystem functioning and long-term stability.
Ecosystem Stability
- A Stable Ecosystem Shows
- Consistent productivity year after year
- Resistance or resilience to disturbances
- Resistance to invasion by alien species
David Tilman’s Experimental Findings
- David Tilman demonstrated experimentally that:
- Higher species diversity → Lower year-to-year variation in biomass
- More diverse ecosystems → Higher productivity
- Conclusion
- Greater biodiversity enhances ecosystem stability, resilience, and overall performance.
Rivet Popper Hypothesis
- Proposed By
- Paul Ehrlich
- Analogy
- Ecosystem = Airplane
- Species = Rivets
- If a few rivets are removed → Plane continues to fly.
- If many rivets are removed → Plane becomes unstable.
- Critical Species
- Loss of keystone species (like rivets on wings) is far more dangerous than loss of less critical species.
- Key Idea
- Each species contributes to ecosystem integrity.
- Cumulative loss increases the risk of collapse.
Loss of Biodiversity
- Human activities are the major drivers of biodiversity decline.
Recorded Extinctions
- IUCN Red List (2004)
- 784 species extinct in last 500 years
– 338 vertebrates
– 359 invertebrates
– 87 plants
- 784 species extinct in last 500 years
- Examples of Recent Extinctions
- Dodo (Mauritius)
- Quagga (Africa)
- Thylacine (Australia)
- Steller’s Sea Cow (Russia)
- Three tiger subspecies (Bali, Javan, Caspian)
- Colonization Impact
- >2,000 native bird species extinct in Pacific Islands due to human colonization
Current Extinction Scenario
- Threatened Species Worldwide
- >15,500 species at risk
- Percent Threatened
- 12% of birds
- 23% of mammals
- 32% of amphibians
- 31% of gymnosperms
- Most vulnerable group → Amphibians
- Current Extinction Rate
- 100–1000 times faster than pre-human rates
- Prediction
- Nearly half of existing species may disappear within the next 100 years if current trends continue.
Historical Extinctions
- Five mass extinctions occurred before humans.
- Examples
- Permian extinction (~225 million years ago) → 90% marine invertebrates vanished
- K–T boundary extinction (~65 million years ago) → Dinosaurs disappeared
- Pleistocene extinction → Woolly mammoth and mastodon vanished
- Present Phase
- Often referred to as the Sixth Mass Extinction — largely anthropogenic.
Consequences of Biodiversity Loss
- Decline in plant productivity
- Reduced resistance to drought and stress
- Greater variability in ecosystem processes
- Increased pest and disease outbreaks
Biodiversity loss weakens ecological networks and threatens long-term human survival.
Causes of Biodiversity Loss (The Evil Quartet)
- The present accelerated extinction rate is largely due to human activities.
- Four major causes are collectively called the Evil Quartet:
- Habitat loss and fragmentation
- Over-exploitation
- Alien species invasion
- Co-extinctions
1. Habitat Loss and Fragmentation
Main Cause
- Destruction of natural habitats is the primary driver of species extinction.
- Forms of Habitat Destruction
- Deforestation
- Filling wetlands
- Ploughing grasslands
- Construction of dams, reservoirs, roads
- Urban expansion
- Why Habitat Loss is Dangerous
- Eliminates shelter and breeding grounds
- Increases predation risk
- Destroys endemic species
- Forces migration to unsuitable habitats
- Tropical Rainforests – A Dramatic Example
- Earlier coverage → 14% of Earth’s land surface
- Present coverage → ~6%
- Amazon Rainforest
- Known as “lungs of the planet”
- Cleared for soybean cultivation and cattle grazing
- Harbours millions of species
Fragmentation
- Definition
- Large continuous habitats are broken into smaller isolated patches.
- Consequences
- Disruption of ecological interactions
- Species restricted to deep forest areas are lost
- Reduced genetic exchange
- Migratory species lose routes
- Animals requiring large territories (e.g., mammals, birds) are severely affected
- Even when some habitat remains, fragmentation drastically reduces biodiversity.
2. Over-Exploitation
- Definition
- Excessive use of biological resources beyond sustainable limits.
- Causes
- Hunting
- Poaching
- Overfishing
- Commercial harvesting
- Human greed
- Historical Extinctions
- Dodo
- Passenger pigeon
- Steller’s Sea Cow
- Three tiger subspecies
- Current Concern
- Decline of global marine fish populations
- Many commercially important fish species nearing endangerment
When population size falls below a critical threshold, recovery becomes difficult → extinction risk rises.
3. Alien Species Invasion
- Definition
- Introduction of non-native species into new ecosystems (intentional or accidental).
- Why Dangerous?
- Absence of natural predators
- Rapid reproduction
- Outcompete native species
- Disrupt food webs
Major Examples
- Nile Perch – Lake Victoria
- Introduced predator fish
- Caused extinction of >200 native cichlid species
- Water Hyacinth (Eichhornia crassipes)
- Introduced to reduce pollution
- Clogged wetlands and rivers
- Destroyed aquatic ecosystems
- Other Invasive Species
- Lantana camara → Replaced native forest plants
- Parthenium hysterophorus (Carrot grass) → Displaced local herbs
- African catfish (Clarias gariepinus) → Threatens native Indian catfish
Island ecosystems are particularly vulnerable due to limited species diversity.
4. Co-Extinctions
- Definition
- Extinction of one species leading to extinction of another species dependent on it.
- Occurs In
- Obligate mutualism
- Host–parasite relationships
- Plant–pollinator interactions
- Examples
- If host fish becomes extinct → Its parasites also disappear
- Co-evolved plant–pollinator pairs may vanish together
Extinction rarely occurs in isolation due to ecological interdependence.
Additional Human-Induced Factors (not mentioned in NCERT)
Disturbance and Degradation
- Natural
- Jungle fires
- Pest outbreaks
- Tree fall
- Human-Induced
- Deforestation
- Repeated burning
- Resource extraction
- Pollution
- Pesticides → Biomagnification
- Heavy metals → Aquatic mortality
- Oil spills → Marine life death
- Air pollutants → Plant damage
- Radiation → Genetic harm
- Intensive Agriculture
- Replacement of diverse habitats with monocultures
- Loss of genetic diversity
- Forestry Practices
- Pure stands (only sal or teak)
- Increased vulnerability to pests and diseases
IUCN Red List Categories
- Extinct (EX) → Completely eliminated
- Extinct in the Wild (EW) → Survives only in captivity
- Critically Endangered (CR) → Extremely high risk
- Endangered (EN) → High risk
- Vulnerable (VU) → Likely to become endangered
- Lower Risk → Needs monitoring
- Data Deficient (DD) → Insufficient information
- Rare species → Naturally small populations
- Not Evaluated → Yet to be assessed
Biodiversity Conservation
- Definition
- Biodiversity conservation means protection, scientific management and sustainable use of biological diversity so that it benefits present and future generations.
- Conservation aims to:
- Maintain species at optimum levels
- Prevent extinction
- Ensure long-term ecological balance
- Provide sustainable benefits
Why Should We Conserve Biodiversity?
- The reasons are grouped into three major categories:
- Narrowly utilitarian (direct economic benefits)
- Broadly utilitarian (ecosystem services)
- Ethical / intrinsic value
1. Narrowly Utilitarian Argument
Direct Economic Benefits
- Humans derive numerous products from biodiversity:
- Food: Cereals, Pulses, Fruits
- Fuel and Materials: Firewood, Fibre, Construction materials
- Industrial Products: Tannins, Dyes, Lubricants, Resins, Perfumes
Medicinal Importance
- More than 25% of modern drugs are plant-derived
- Around 25,000 plant species are used in traditional medicine systems
Bioprospecting
- Definition
- Exploration of biodiversity for economically valuable genes, molecules or species.
- Importance
- Countries rich in biodiversity can gain major economic advantages through research and sustainable use.
2. Broadly Utilitarian Argument
Ecosystem Services
- Biodiversity maintains essential life-support systems.
- Major ecosystem services include:
- Oxygen Production
- Tropical forests such as the Amazon contribute significantly to atmospheric oxygen through photosynthesis.
- Pollination
- Bees, birds and bats pollinate crops. Artificial pollination would be extremely costly and inefficient.
- Climate Regulation
- Forests store carbon and help regulate global climate.
- Soil Formation and Nutrient Cycling
- Microorganisms maintain soil fertility and productivity.
- Water Purification
- Wetlands naturally filter pollutants.
- Aesthetic and Recreational Value
- Walking in forests
- Watching flowering landscapes
- Listening to birds
- Oxygen Production
- These improve psychological and emotional well-being.
3. Ethical / Intrinsic Value Argument
- Core Principle
- Every species has inherent value, irrespective of its economic utility.
- Moral Responsibility
- Humans share Earth with millions of species
- We have an ethical duty to protect them
- Conservation ensures resources for future generations
- This argument emphasizes respect for life and intergenerational responsibility.
Red List – Purpose and Importance (not mentioned in NCERT)
Purpose of IUCN Red List
- Create awareness about extinction risks
- Provide global biodiversity status index
- Identify threatened species
- Help set conservation priorities
- Support international agreements such as CITES and CBD
Major Categories
- Extinct (EX)
- Extinct in the Wild (EW)
- Critically Endangered (CR)
- Endangered (EN)
- Vulnerable (VU)
- Data Deficient (DD)
- Not Evaluated
How Do We Conserve Biodiversity?
- Two major strategies:
- In-situ conservation
- Ex-situ conservation
In Situ Conservation (Conservation in natural habitat)
- Definition
- Protection of entire ecosystems so species survive in their original environment.
Core idea: “Save the whole forest to save the tiger.”
A. Biodiversity Hotspots
- Definition
- Regions with high species richness and high endemism under severe threat.
- Identified by Norman Myers.
- Criteria
- High species diversity
- High endemism
- Severe habitat loss
- High exploitation pressure
- Global Hotspots
- 34 recognized worldwide
- India’s Hotspots
- Western Ghats–Sri Lanka
- Indo-Burma
- Himalaya
Hotspots cover less than 2% of Earth’s land but support a large share of global biodiversity.
B. Protected Areas
- Definition
- Legally designated regions for biodiversity protection.
- Types
- National Parks
- Wildlife Sanctuaries
- Biosphere Reserves
1. National Parks
- Strict protection
- No grazing or cultivation
- Managed by government
- Examples: Kaziranga, Bandipur
2. Wildlife Sanctuaries
- Protection mainly of fauna
- Limited human activities permitted
- Grazing and resource use may be allowed
3. Biosphere Reserves
- Initiated under UNESCO’s Man and Biosphere (MAB) Programme.
- Zonation
- Core Zone
- Completely protected
- No human interference
- Buffer Zone
- Research and limited resource use allowed
- Transition Zone
- Human settlements and sustainable activities allowed
- Core Zone
Sacred Groves – Traditional Conservation
- Community-protected forest patches based on religious beliefs.
- Found in:
- Khasi and Jaintia Hills (Meghalaya)
- Aravalli Hills (Rajasthan)
- Western Ghats (Karnataka, Maharashtra)
- Sarguja, Chanda, Bastar (Madhya Pradesh)
- Importance:
- Protect endemic and rare species
- Preserve genetic diversity
Ex Situ Conservation (Conservation Outside Natural Habitat)
- Definition
- Ex-situ conservation is the protection of endangered species outside their natural habitats in specially designed settings.
- Purpose
- Rescue critically endangered species
- Preserve genetic material
- Support reintroduction into the wild
- Provide genetic resources for breeders and scientists
Core idea: When the natural habitat cannot protect a species, the species is protected separately.
Major Methods of Ex-situ Conservation
- Off-site collections
- Gene banks
- Advanced biotechnological methods
I. Off-site Collections
- Definition
- Live collections of species maintained outside their natural habitats.
- Examples
- Zoological parks
- Botanical gardens
- Wildlife safari parks
- Arboreta
- Functions
- Maintain living specimens
- Conduct captive breeding programmes
- Create public awareness and education
Captive Breeding
- Enables survival of species extinct in the wild
- Population increased under protection
- Individuals may be selectively released into natural habitats
II. Gene Banks
- Definition
- Facilities that preserve genetic material of plants and animals for long-term conservation.
- Materials Preserved
- Viable seeds
- Live plants
- Tissue cultures
- Frozen germplasm
- Gametes and embryos
- Purpose:
- Preserve maximum genetic variability for future use.
Seed Banks
- Seeds stored under controlled conditions.
- Orthodox Seeds
- Tolerate low moisture (~5%)
- Survive low temperature (-10°C to -20°C)
- Long-term storage possible
- Examples: cereals, legumes
- Recalcitrant Seeds
- Cannot tolerate drying
- Cannot tolerate low temperature
- Short storage duration
- Examples: litchi, oil palm
- Such species require alternative methods like cryopreservation or tissue culture.
III. Advanced Techniques
Cryopreservation
- Definition
- Preservation of biological material at -196°C using liquid nitrogen.
- Material Preserved
- Embryos
- Gametes
- Animal cells
- Plant tissues
- Advantages
- Indefinite storage
- Maintains genetic stability
- Useful for species with recalcitrant seeds
- Examples: cocoa, coconut, jackfruit
Tissue Culture
- Definition
- In vitro growth of plant tissues under sterile conditions.
- Techniques
- Callus culture
- Embryoid formation
- Shoot tip culture
- Pollen grain culture
- Advantages
- Rapid multiplication
- Hybrid rescue
- Maintains large genotypes in small space
- Examples: banana, potato
In Vitro Fertilization (IVF)
- Fertilization outside the body
- Used for endangered animals
- Supports population recovery
Gamete Preservation
- Storage of sperm and ova
- Maintains future breeding potential
In-situ vs Ex-situ (Quick Contrast)
- In-situ
- Protection in natural habitat
- Conserves ecosystem + species
- Ex-situ
- Artificial/special settings
- Conserves individual species + genes
Global Efforts for Biodiversity Conservation
1992 – Convention on Biological Diversity (CBD)
- Location: Rio de Janeiro (Earth Summit)
- Signed by 152 nations
- Came into force on 29 December 1993
- India joined in May 1994
- Major commitments:
- Conserve biodiversity
- Promote sustainable use
- Ensure equitable sharing of genetic resource benefits
Produced Agenda 21 – blueprint for sustainable development.
2002 – World Summit on Sustainable Development
- Location: Johannesburg
- 190 countries pledged to reduce biodiversity loss by 2010
2012 – Rio+20 Summit
- Held again in Rio de Janeiro
- Revised global sustainable development strategies
Important International Organisations
- International Union for Conservation of Nature – Global conservation leadership
- World Wide Fund for Nature – Wildlife conservation initiatives
- Convention on International Trade in Endangered Species of Wild Fauna and Flora – Controls trade of endangered species
- United Nations Educational, Scientific and Cultural Organization – Supports Biosphere Reserves under MAB Programme
Trade restrictions (e.g., ivory ban) have helped reduce elephant poaching.
Biodiversity Conservation in India
- India holds 8.1% of global biodiversity with only 2.4% of land area.
- Thus, conservation efforts are globally significant.
In-situ Measures
- Conducted by Ministry of Environment and Forests.
- Joint Forest Management (JFM)
- Covers ~10.25 million hectares
- 36,000+ village forest protection committees
- Involves local and tribal communities
- Protects non-wood forest products
- Tribal & Traditional Conservation
- Conservation of land races
- Preservation of medicinal plants
- Community-based conservation practices
Ex-situ Measures in India
- Managed by:
- National Bureau of Plant Genetic Resources
- National Bureau of Animal Genetic Resources
- National Bureau of Fish Genetic Resources
- ICRISAT – Hyderabad
- International Crops Research Institute for the Semi-Arid Tropics
- Conserves germplasm of:
- Groundnut
- Pigeon pea
- Chickpea
- Pearl millet
- Sorghum
Numerous centres across India preserve present and historical crop varieties.
Chapter Summary
ORIGIN AND SCALE OF LIFE
- Life on Earth began approximately 3.8 billion years ago.
- Over millions of years, evolution generated enormous biological diversity.
- Currently:
- More than 1.5 million species have been described.
- Estimated total species ≈ 6–7 million (many undiscovered, especially in tropics).
- Taxonomic Distribution
- >70% recorded species are animals.
- Insects constitute >70% of animal species.
- Fungi have more species than all vertebrates combined.
LEVELS OF BIODIVERSITY
- Biodiversity exists at three hierarchical levels:
- Genetic Diversity: Variation within a species (genes, alleles, strains).
- Species Diversity: Variety and richness of species in a region.
- Ecosystem Diversity: Variety of ecosystems, habitats, and ecological processes.
INDIA’S BIODIVERSITY STATUS
- India has only 2.4% of the world’s land area.
- Supports about 8.1% of global species diversity.
- ~45,000 plant species recorded.
- ~90,000 animal species recorded.
- Classified among the 12 mega-diverse countries.
PATTERNS OF BIODIVERSITY
- Latitudinal Gradient
- Species diversity:
- Highest → Tropics
- Decreases → Toward poles
- Reasons for High Tropical Diversity:
- Longer evolutionary time (no glaciation disturbances).
- Stable and less seasonal climate.
- Greater solar energy → higher primary productivity.
- Species diversity:
- Species–Area Relationship
- Species richness increases with area.
- Expressed as: log S = log C + Z log A
- Larger regions show steeper slopes (higher Z value).
IMPORTANCE OF BIODIVERSITY
- Ecological Importance
- Greater stability
- Higher productivity
- Resistance to invasive species
- Better resilience to environmental stress
- Experimental Evidence
- Communities with higher species richness:
- Show less year-to-year variation in biomass.
- Maintain ecosystem functioning more efficiently.
- Communities with higher species richness:
- Conceptual Model
- Rivet Popper Hypothesis:
- Each species contributes to ecosystem stability like rivets in an airplane.
- Loss of key species can destabilize the entire system.
- Rivet Popper Hypothesis:
LOSS OF BIODIVERSITY
- Current extinction rates:
- 100–1000 times higher than pre-human background rates.
- Recent Data:
- >700 species extinct in recent centuries.
- >15,500 species currently threatened.
- Threatened Groups
- 12% birds
- 23% mammals
- 32% amphibians
- 31% gymnosperms
- If trends continue, nearly half of species may disappear within 100 years.
CAUSES OF BIODIVERSITY LOSS (Evil Quartet)
- Habitat Loss and Fragmentation
- Primary cause of extinctions.
- Tropical rainforest cover reduced from 14% to ~6%.
- Overexploitation
- Unsustainable hunting, fishing, logging.
- Examples: Passenger pigeon, Steller’s sea cow.
- Alien Species Invasion
- Introduced species outcompete natives.
- Example: Nile perch in Lake Victoria.
- Co-extinction
- Loss of one species leads to extinction of dependent species.
WHY BIODIVERSITY IS CRUCIAL
- Narrowly Utilitarian Value
- Food
- Fuel
- Fibre
- Medicines (25% modern drugs plant-derived)
- Bioprospecting potential
- Broadly Utilitarian (Ecosystem Services)
- Oxygen production
- Pollination
- Climate regulation
- Nutrient cycling
- Soil formation
- Ethical Value
- Every species has intrinsic worth.
- Moral responsibility to preserve biodiversity for future generations.
CONSERVATION STRATEGIES
- Two Major Approaches:
1. In Situ Conservation
- Protection within natural habitats.
- Includes:
- 34 global biodiversity hotspots
- 3 hotspots covering India (Himalaya, Indo-Burma, Western Ghats–Sri Lanka)
- Biosphere reserves
- National parks
- Wildlife sanctuaries
- Sacred groves
- India:
- 14 Biosphere Reserves
- 90 National Parks
- 450+ Wildlife Sanctuaries
2. Ex Situ Conservation
- Protection outside natural habitats.
- Methods:
- Zoological parks
- Botanical gardens
- Seed banks
- Tissue culture
- In vitro fertilization
- Cryopreservation of gametes
CORE POINTS
- Biodiversity:
- Result of billions of years of evolution.
- Unevenly distributed (highest in tropics).
- Essential for ecosystem stability and human survival.
- Currently declining at alarming rates due to human activities.
Conservation is not optional — it is essential for sustaining life on Earth.