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Biodiversity and 12 its conservation CHAPTER Nilgiri tahr is an endangered in the IUCN Red List of Threatened Species due to hunting and poaching Chapter outline

12.1 wide variety of living including 12.2 Importance of biodiversity – Global Aplants, and micro-organisms with and whom we share this planet makes the world 12.3 Biogeographical regions of India a beautiful place to live in. Living organisms exist 12.4 Threats to biodiversity almost everywhere from mountain peaks to the 12.5. Causes of Biodiversity Loss ocean depths; from deserts to the rainforests. 12.6 IUCN They vary in their and behaviour, shape, size and colour. The remarkable diversity of 12.7 Biodiversity and its conservation living organisms forms an inseparable and 12.8 Restoration of degraded significant part of our planet, however, the ever 12.9 Biodiversity Act (BDA) increasing is posing serious threats to bio-diversity. In this chapter, we shall discuss biodiversity – concepts, levels, magnitude Learning objectives and patterns, importance of biodiversity, biogeographical regions of India, threats to ➢ Acquire knowledge about concept, biodiversity, causes of biodiversity loss, , level and patterns of biodiversity. and biodiversity conservation. ➢ Appreciate the magnitude of India’s biodiversity. 12.1 Biodiversity ➢ Understand The 1992 UN Earth Summit defined biogeographical regions Biodiversity as the variability among living and resources of India. organisms from all sources, including ➢ Gain insight into the terrestrial, marine and other aquatic threats to biodiversity. ➢ Understand the reasons/ and the ecological complexes of which they are causes and effects of extinction. a part. This includes diversity within species, ➢ Create awareness to restore degraded between species and ecosystems of a region. habitats and environment. It reflects the number of different organisms ➢ To be aware of the Biodiversity Act and their relative frequencies in an ecological and its provisions. system and constitutes the most important functional component of a natural .

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TN_GOVT_XII_Zoology_chapter 12.indd 213 25-02-2019 18:45:09 It helps to maintain ecological processes, Genetic diversity create soil, recycle nutrients, influence climate, degrade waste and control diseases. It provides an index of health of an ecosystem.The survival of human race depends on the existence and wellbeing of all forms ( and animals) Genetic diversity in a whole population in the . Species diversity 12.1.1 Concept of biodiversity The term biodiversity was introduced by Walter Rosen (1986). Biodiversity is the assemblage of different life forms. Each species

is adapted to live in its specific environments. Species diversity in a coastal redwood ecosystem The changes in climatic conditions are

reflected in the distribution and pattern of Ecosystem diversity biodiversity on our planet. The number of species per unit area declines as we move from tropics towards the poles. The Tundra and Taiga of northern Canada, Alaska, northern and Russia possess less than

12 species of trees. The temperate forests of and ecosystem diversity the United states have 20-35 species of trees, across the landscape while the tropical forests of Panama have over of an entire region 110 species of trees in a relatively small area. Fig. 12.1 Three levels of biodiversity formation of different races, varieties and 12.1.2 Levels of biodiversity . Rouwolfia vomitaria, a medicinal Edward Wilson popularized the term growing in different ranges of the ‘Biodiversity’ to describe diversity at all levels Himalayas shows differences in the potency of biological organization from to and concentration of the active ingredient biomes. There are three levels of biodiversity reserpine due to genetic diversity. Genetic – Genetic diversity, Species diversity and diversity helps in developing to Community/Ecosystem diversity (Fig. 12.1). changing environmental conditions. Genetic diversity refers to the differences Species diversity refers to the variety in genetic make-up (number and types of ) in number and richness of the species in any between distinct species and to the genetic . The number of species per unit area at variation within a single species; also covers a specific time is called species richness, which genetic variation between distinct populations denotes the measure of species diversity. The of the same species. Genetic diversity can Western Ghats have greater species be measured using a variety of molecular diversity than the Eastern Ghats. The more techniques. India has more than 50,000 genetic the number of species in an area the more is variants of Paddy and 1000 variants of Mango. the species richness (Fig. 12.1a). The three Variation of genes of a species increases with indices of diversity are - Alpha, Beta and diversity in size and habitat. It results in the Gamma diversity

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TN_GOVT_XII_Zoology_chapter 12.indd 214 25-02-2019 18:45:09 i. Alpha diversity: It is measured by counting described. Each year about 10-15 thousand the number of taxa (usually species) within new species are identified and published a particular area, community or ecosystem. worldwide, of which 75% are invertebrates. The ii. Beta diversity: It is species diversity number of undescribed species is undoubtedly between two adjacent ecosystems and is much higher. obtaining by comparing the number of India is very rich in terms of biological species unique to each of the ecosystem. diversity due to its unique bio-geographical iii. Gamma diversity refers to the diversity location, diversified climatic conditions and of the habitats over the total landscape or enormous eco-diversity and geo-diversity. geographical area. According to world biogeographic classification, iii. Gamma diversity: It refers to the diversity India represents two of the major realms of the habitats over the total landscape or (The Palearctic and Indo-Malayan) and three geographical area. biomes (Tropical humid forests, Tropical Dry/ Deciduous forests and Warm Deserts/Semi deserts). With only about 2.4% of the world’s total land surface, India is known to have over 8 % of the species of animals that the world holds and this percentage accounts for about 92,000 known species. India is the seventh largest country in the world in terms of area. India has a variety of ecosystems, biomes with its varied habitats like, hills, valleys, plateaus, sea shores, Fig. 12.1a Species biodiversity mangroves, estuaries, glaciers, grasslands Community/Ecosystem diversity is the and river basins. It also reflects different variety of habitats, biotic communities, and kinds of climates, precipitation, temperature ecological processes in the biosphere. It is the distribution, river flow and soil. India is one diversity at ecosystem level due to diversity of of the 17 mega biodiversity countries of the niches, trophic levels and ecological processes world and has ten biogeographic zones with like nutrient cycles, food webs, flow characteristic habitat and biota. and several biotic interactions. India with its alpine meadows, rain forests, mangroves, "The world is currently undergoing a very coral reefs, grass lands and deserts has one of rapid loss of biodiversity comparable the greatest ecosystem diversity on earth. with the great mass extinction events 12.1.3 Magnitude of biodiversity that have previously occurred only five or six times in the earth's history." Biodiversity is often quantified as the - World Fund number of species in a region at a given time. The current estimate of different species on earth is around 8-9 million. However, we really 12.1.4 Patterns of biodiversity don’t know the exact magnitude of our natural distribution wealth. This is called the ‘The Taxonomic The distribution of plants and animals impediment’. So far about 1.5 million species of is not uniform around the world. Organisms , animals and plants have been require different sets of conditions for their

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TN_GOVT_XII_Zoology_chapter 12.indd 215 25-02-2019 18:45:10 optimum and growth. Within this optimal range (habitat) a large number and of organisms are likely to occur, grow and multiply. The habitat conditions are determined by their latitudes and altitudes. MSL.171.91m Latitudinal and altitudinal gradients: Temperature, precipitation, distance from the equator (latitudinal gradient), altitude from sea level (altitudinal gradient) are some of the factors that determine biodiversity distribution patterns. The most important pattern of biodiversity is Mean Sea Level (MSL) is an average latitudinal gradient in diversity. This means level of the surface of one or more of that there is an increasing diversity from the Earth’s oceans (or seas) from which poles to equator. Diversity increases as one heights such as elevations may be moves towards the temperate zones and reaches measured. the maximum at the tropics. Thus, tropics As we travel by train we notice names harbour more biodiversity than temperate or of stations on big yellow signboards polar regions, especially between the latitudes on which is usually written how much of 23.5⁰N and 23.5⁰S (Tropic of Cancer to the elevated that place is compared to MSL. Tropic of Capricorn). Harsh conditions exist in temperate areas during the cold seasons while For example, Erode junction is about very harsh conditions prevail for most of the year 171 meters above MSL. in polar regions. Columbia located near the equator (0⁰) has but also for supporting both variety and nearly 1400 species of while New York at number of organisms. 41⁰N has 105 species and Greenland at 71⁰N has 56 species. India, with much of its land area • The temperatures vary between 25⁰C to in the tropical latitudes, is home for more than 35⁰C, a range in which most metabolic 1200 species of birds. Thus it is evident that the activities of living organisms occur with latitude increases the species diversity. ease and efficiency. Decrease in species diversity occurs as • The average rainfall is often more than one ascends a high mountain due to drop in 200 mm per year. temperature (temperature decreases @ 6.5⁰ C • Climate, seasons, temperature, humidity, per Km above mean sea level) photoperiods are more or less stable and The reasons for the richness of encourage both variety and numbers. biodiversity in the Tropics are: • Rich and nutrient availability. • Warm tropical regions between the tropic of Cancer and Capricorn on either side Species - Area relationships of equator possess congenial habitats for German Naturalist and Geographer living organisms. explored the • Environmental conditions of the tropics wilderness of south American jungles and are favourable not only for found that within a region the species richness increased with increasing area but upto a

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TN_GOVT_XII_Zoology_chapter 12.indd 216 25-02-2019 18:45:10 certain limit. The relationship between species of flora and including microorganisms. richness and area for a wide variety of taxa These organisms can inhabit different (angiosperm plants, birds, bats, freshwater ecosystems with varying conditions like the ) turned out to be the rectangular Rainforests, Coral reefs, Grasslands, Deserts, hyperbola. On a logarithmic scale, the Tundra and the Polar ice caps. This variety relationship is a straight line described by the (Biodiversity) is essential for the wellbeing of equation. our planet and sustenance of life as a whole. log S = log C + Z log A The importance of biodiversity can be viewed and measured as where a) Ecosystem services b) Biological S = Species richness resources c) Social benefits of biodiversity A = Area Z = Slope of the line (regression The organization and functioning coefficient) of ecosystems world over is effected and C = Y-intercept dependent on biodiversity and its richness. The major functional attributes are: • continuity of nutrient cycles or S=CAz biogeochemical cycles (N2, C, H2O, P, S cycles)

s • soil formation, conditioning or maintenance of soil health (fertility) by soil microbial diversity along with the log S = log C + Z log A log-log scale different trophic members

Species richnes • increases ecosystem and

(S) provide food resources (A) Area (S) • act as water traps, filters, water flow Fig. 12.2 Species - Area relationship on regulators and water purifiers (forest log scale cover and vegetation) • climate stability (forests are essential for Regression coefficient Z generally has a rainfall, temperature regulation, CO2 value of 0.1-0.2 regardless of taxonomic group absorption, which in turn regulate the or region. However, in case of the species – density and type of vegetation) area relationship in very large areas like entire • forest resource management and continents, the slope of the line appears to be sustainable development much steeper (Z-value in the range of 0.6- 1.2). For example, in case of the fruit eating • maintaining balance between biotic (frugivorous) birds and in the tropical components forests of different continents, the slope is found • cleaning up of pollutants – microbes to be a steeper line of 1.15 (Fig. 12.2) are the biggest degraders of including many anthropogenic ones 12.2 Importance of biodiversity – which are present in effluents, sewage, Global and India garbage and agro-chemicals Biodiversity is the variety of life on earth. • ecological stability – the varieties and That is, it is the number of different species richness of species contribute to ecological

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TN_GOVT_XII_Zoology_chapter 12.indd 217 25-02-2019 18:45:10 stability and survival of species. Biodiverse fauna include Chiru and Black-rocked regions are reservoirs of biological Crane. resources like food resources, pool, 2. Himalayas: The entire mountain chain genetic resource, medicinal resources, running from north-western to north- bio-prospecting eastern India, comprising a diverse range • to provide unique aesthetic value and hot of biotic provinces and biomes and covers spots for Ecotourism. Along with forest 7.2% of the country’s landmass. The resources and wildlife it has commercial common fauna of the Himalayan ranges, significance are the wild sheep, mountain goats, shrew, • an indicator of the health of the ecosystem. snow leopard and panda, many of which Endemism is a crucial indicator of are endangered. richness. 3. Indian Desert: The extremely arid area west of the Aravalli hill range, comprising The interrelationship both the salty desert of Gujarat and the and interdependence of sand desert of Rajasthan. It comprises all living components 6.9% of the country’s land-mass. Wild in a system can be seen ass is endemic to this region. It is also from the example of the the habitat for the Indian Bustard, camel, fruit bats of Guam (South East Asia). The foxes and , many of which are fruit bats are a delicacy here, and hence endangered. their population has dwindled which is 4. Semi – Arid Zones: This zone is between not surprising. What is surprising is that the desert and the Deccan plateau, local fruit production has got affected including the Aravalli hill range covering as it was identified that the bats served 15.6% of the country’s landmass. Fauna as pollinators. Hence there is a need for found here are nilghai, blackbuck, four conservation of diversity as that could horned antelopes, sambar, chital and avert such situations. spotted deer which are herbivores along with predators like Asiatic lion, tiger, 12.3 Biogeographical regions of leopard and jackal. India 5. Western Ghats: Western Ghats, are mountain ranges along the west coast of As per the international ‘biome’ type India, extending over almost 1,500km of classification based upon climate, fauna from Sat Pena in south Gujarat to the and flora and the soil conditions, India can southernmost tip of Kerala. The annual be divided into ten different biogeographic rainfall is about 2000 mm. This zone has zones, (Fig. 12.3) namely: large populations of Nilgiri tahr (State 1. Trans Himalayan Region: An extension of ), Nilgiri langur, of the Tibetan plateau, high-altitude cold tiger, leopard, and Indian elephant.The desert in Ladakh (J&K) and Lauhala Spiti grizzled squirrel and lion tailed macaque (H.P) comprising 5.7% of the country’s are endemic to this region. landmass. The mountains of this region 6. Deccan Peninsula: This covers much have the richest wild sheep and goat of the southern and south-central community in the world, renowned for its plateau with a predominantly deciduous quality wool and wool products. Other

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TN_GOVT_XII_Zoology_chapter 12.indd 218 25-02-2019 18:45:10 Trans-Himalaya

Himalaya Semi arid

Gangetic plains Desert North east

Deccan peninsula Coastal

Western ghats

Island

Fig. 12.3 Biogeographical regions of India

vegetation and 4.3% of the country’s the Himalayan foothills. Fauna includes landmass. It is known for deciduous rhinoceros, elephant, buffalo, swamp forests, thorn forests and pockets of semi deer, hog-deer. ever green forests. Fauna found here are 8. North-East India: The plains and non- Chital, Sambhar, Nilghai, elephant, sloth Himalayan hill ranges of north eastern bear, black buck and barking deer. It is the India are home to a wide variety of catchment area of major Indian rivers like vegetation. With 5.2% of the country’s Godavari, Tapti, Narmada and Mahanadi. landmass, this region represents the 7. Gangetic Plains: These plains are transition zone between the Indian, relatively homogenously defined by the Indo-Malayan and Indo-Chinese bio- Ganges river system and occupy about geographical regions and is the meeting 11% of the country’s landmass. This point of the Himalayan Mountains and region is very fertile and extends up to

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TN_GOVT_XII_Zoology_chapter 12.indd 219 25-02-2019 18:45:11 peninsular India. The North-East is Some of the other threats include thus the biogeographical ‘Gateway’ for specialised diet, specialized habitat much of India’s fauna and flora and also requirement, large size, small population biodiversity hotspot (Eastern Himalaya), size, limited geographic distribution and which includes the Indian rhinoceros, high economic or commercial value. Large leopard and golden langur. mammals by virtue of their size require 9. Coastal Region: Coastal region of India larger areas to obtain the necessities of with sandy beaches, mud flats, coral reefs, life - food, cover, mates than do smaller mangroves constitutes 2.5% of the total mammals. Individual home range of Lion geographical area. The coastline from can be about 100 square Km. Mammals have Gujarat to Sundarbans is estimated to be specialized dietary needs such as carnivores, 5423km long. Apart from this a total of 25 frugivores and the need to forage over much islets constitute the Lakshadweep, which larger areas than general dietary herbivores are of coral origin and have a typical reef and omnivores. Mammals also have low lagoon system, rich in biodiversity. The reproductive output other than small rodents. fauna includes native crabs, turtles and tunas 12.5 Causes of biodiversity loss 10. Andaman and Nicobar Islands:The The major causes for biodiversity decline are: Andaman and Nicobar Islands in the • Habitat loss, fragmentation and Bay of Bengal have highly diverse set of destruction (affects about 73% of all biomes, constituting 0.3% of the total species) geographical area. They are centers of high endemism and contain some of India’s • Pollution and pollutants (smog, pesticides, finest evergreen forests and support a herbicides, oil slicks, GHGs) wide diversity of corals. Fauna includes • Narcondam hornbills of the Andamans and the South Andaman Krait. • Introduction of alien/exotic species 12.4 Threats to biodiversity • Over exploitation of resources (poaching, indiscriminate cutting of trees, over Even though India is one of the 17 identified fishing, hunting, mining) mega diverse countries of the world, it faces lots of threats to its biodiversity. • Intensive agriculture and aquacultural practices Apart from natural causes, human activities, both directly and indirectly are today’s • Hybridization between native and non- main reason for habitat loss and biodiversity native species and loss of native species loss. Fragmentation and degradation due to • Natural disasters (Tsunami, forest fire, agricultural practices, extraction (mining, earth quake, volcanoes) fishing, logging, harvesting) and development (settlements, industrial and associated • Industrialization, Urbanization, infrastructures) leads to habitat loss and infrastructure development, Transport – fragmentation leads to formation of isolated, Road and Shipping activity, communication small and scattered populations and as towers, dam construction, unregulated .

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TN_GOVT_XII_Zoology_chapter 12.indd 220 25-02-2019 18:45:11 tourism and monoculture are common area of specific threats Where are the Sparrows? • Co-extinction Common Sparrows are going extinct because of mindless urbanization. They Habitat Loss are losing not just their natural habitats Development of human society is but also the essential human touch they inevitable. Natural habitats are destroyed need and thrive upon. The population of for the purpose of settlement, agriculture, sparrows is dwindling due to the use of mining, industries and construction of packed food, insecticides in farming and highways. As a result species are forced to changing lifestyles, and match box-styled adapt to the changes in the environment or architecture resulting in an inadequate move to other places. If not, they become availability of food and shelter for the birds. victim to predation, starvation, disease and Unlike pigeons that can make nests on eventually die or results in human animal ledges, sparrows need cavities to build their conflict. nests. Over population, urbanization, industrialization and agricultural Habitat fragmentation advancements require additional land, Habitat fragmentation is the process water and raw materials every year. This is where a large, continuous area of habitat is made possible only through fragmentation both, reduced in area and divided into two or or destruction of natural habitats by filling more fragments. Fragmentation of habitats wetlands, ploughing grasslands, cutting down like forest land into crop lands, orchard lands, trees, forest, desilting rivers, constructing plantations, urban areas, industrial estates, transport and transit systems has resulted in the transport ways, caving mountains, extracting, destruction of complex interactions amongst ores, changing the course of rivers and filling species, (food chain and webs) destruction of of seashore. species in the cleared regions, annihilation of The most dramatic example of habitat species restricted to these habitats (endemic) loss comes from the tropical rainforests 14% of and decreased biodiversity in the habitat the earth’s land surface once covered by these fragments. Animals requiring large territories tropical forests, is not more than 6% now. The such as mammals and birds are severely Amazon rainforest, a vast area, harbouring affected. The elephant corridors and migratory millions of species, also called “Lungs of the routes are highly vulnerable. The dwindling planet”is destroyed and being replaced for of many well-known birds (sparrows) and agriculture and human settlements. 90% of animals can be attributed to this. New Zealand’s wetlands have been destroyed Over exploitation: and cleared for cultivating soya beans and We depend on for our basic needs raising grass for beef cattle. Kodaikanal such as food and shelter. However, when and Nilgiri hills of Tamil Nadu have been the need becomes greed, it leads to over destroyed rapidly for human occupancy. Loss exploitation of natural resources. Excessive of habitat results in annihilation of plants, exploitation of a species, reduces the size of microorganisms and forcing out animals its population to such a level that it becomes from their habitats.

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TN_GOVT_XII_Zoology_chapter 12.indd 221 25-02-2019 18:45:11 vulnerable to extinction. Dodo, passenger Global Climate changes pigeon and Steller’s sea cow have become Industrialization is a major contributor extinct in the last 200-300 years due to over to climate change and a major threat to exploitation by . Overfishing due to biodiversity. Energy drives our industries, population pressure leads to many marine which is provided by burning of fuels.

(populations) declining around the world. This increases the emission of CO2, a GHG, leading to climate change. Due to large scale Exotic species invasion: deforestation, the emitted CO2 cannot be Exotic species (non-native; alien) are absorbed fully, and its concentration in the organisms often introduced unintentionally air increases. Climate change increases land or deliberately for commercial purpose, as and ocean temperature, changes precipitation biological control agents and other uses. They patterns and raises the sea level. This often become invasive and drive away the local inturn results in melting of glaciers, water species and is considered as the second major inundation, less predictability of weather cause for extinction of species. Exotic species patterns, extreme weather conditions, have proved harmful to both aquatic and outbreak of squalor diseases, migration of terrestrial ecosystems. animals and loss of trees in forest. Thus, fish (Jilabi kendai) (Oreochromis climate change is an imminent danger to the mosambicus) introduced from east coast of existing biodiversity (Fig. 12.4). South Africa in 1952 for its high productivity Human into Kerala’s inland waters, became invasive, Anthropogenic Ecosystem GHG and Aerosol Services due to which the native species such as Puntius Emissions Land-use Climate dubius and Labeo kontius face local extinction. Change Impacts Amazon sailfin catfish is responsible for Climate destroying the fish population in the wetlands Impacts Climate Biodiversity Climate of Kolkata. The introduction of the Nile Perch, a Regulation predatory fish into Lake Victoria in East Africa Ecosystem led to the extinction of an ecologically unique Biogenic GHG and Aerosol assemblage of more than 200 nature species Emissions

of cichlid fish in the lake. Biogeochemical Cycles African apple snail (Achatina fulica) is the Fig.Links between12.4 Biodiversity Links, Climate between Change and Humanbiodiversity, Well-being most invasive among all alien fauna in India. climate change and human well - being This mollusc was first reported in the Andaman Shifting or Jhum cultivation (Slash- and Nicobar Islands. It is now found across the and-burn agriculture) country and threatens the habitat of several In shifting cultivation, plots of natural native species. Moreover it is becoming a tree vegetation are burnt away and the cleared vicious pest in vegetable farms. patches are farmed for 2-3 seasons, after Exotic earthworms compete for food with which their fertility reduces to a point where native varieties and deplete their population in crop production is no longer profitable. The soil. Papaya Mealy Bug (Paracoccus marginatus) farmer then abandons this patch and cuts is native of Mexico and Central America, is down a new patch of forest trees elsewhere believed to have destroyed huge crops of papaya for crop production.This system is practiced in Assam, West Bengal and TamilNadu. in north-eastern regions of India. When vast

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TN_GOVT_XII_Zoology_chapter 12.indd 222 25-02-2019 18:45:11 areas are cleared and burnt, it results in loss of Intensive agriculture: forest cover, pollution and discharge of CO2 Spread of agriculture is sometimes at which in turn attributes to loss of habitat and the cost of wetlands, grasslands and forests. climate change which has an impact on the Intensive agriculture is based on a few high faunal diversity of that regions. yielding varieties. As a result, there is reduction in the genetic diversity. It also increases Coextinctions vulnerability of the crop plants to sudden attack Coextinction of a species is the loss of by pathogens and pests. There are only few a species as a consequence of the extinction varieties of traditional paddy strains today due of another. (Eg., orchid bees and forest trees to use to hybrid varieties in Tamil Nadu. by cross pollination). Extinction of one will automatically cause extinction of the other. Forestry Another example for co-extinction is the There is a tendency to grow economically connection between Calvaria tree and the important and viable trees like Teak, Sandal, extinct of Mauritius Island, the Dodo. The Oak, Sal in forests resulting in loss of other forest trees. Calvaria tree is dependent on the Dodo bird for completion of its life cycle. The mutualistic Natural threats association is that the tough horny endocarp of These include spontaneous jungle fires, the seeds of Calvaria tree are made permeable tree fall, land slide, defoliation by insects or by the actions of the large stones in bird's locust attack. gizzard and digestive juices thereby facilitating easier germination. The extinction of the Dodo 12.5.1 Loss of biodiversity bird led to the imminent danger of the Calvaria Species have been evolving and dying tree coextinction. out (extinction) ever since the origin of life. However, species are now becoming extinct at Pollution a faster rate. This is destabilizing the ecological Pollutants and pollution are a major stability and the distribution of biological cause for biodiversity loss. Excessive use of diversity on earth. Human activities greatly fertilisers, pesticides and heavy metals have contribute to the loss of biodiversity. Natural polluted the land, ground and surface water resources such as land, water and organisms bodies. There is a tendency of pesticide are indiscriminately exploited by human biomagnification which results in high beings. concentrations at higher trophic levels According to the Convention of which has resulted in drastic decline in the Biological Diversity, direct and indirect population of fish eating birds and falcons. human activities have a detrimental effect Run off from fertilizer rich fields causes on biodiversity. Direct human activities like nutrient enrichment of water bodies leading to change in local land use, species introduction eutrophication. Mercury, arsenic, cadmium, or removal, harvesting, pollution and climate change contribute a greater pressure on loss of chromium poisoning has led to depletion of biodiversity. Indirect human drivers include biotic resources in vulnerable ecosystems. demographic, economic, technological, Death of vulture population is attributed to cultural and religious factors. the veterinary medicine Diclofenac, which is responsible for the thinning of the egg shells.

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TN_GOVT_XII_Zoology_chapter 12.indd 223 25-02-2019 18:45:11 Even though new species are being Islands (and Myanmar, Thailand, Vietnam, discovered, there is little hope for adding Laos, Cambodia and Southern China) new species through speciation into the d. Sundalands: includes Nicobar group biodiversity treasure. Monsoon failure, global of Islands (and Indonesia, Malaysia, warming, depletion in ozone layer, landslides Singapore, Brunei, Philippines) in hilly states, pollution are a few indirect effects of human activities which results in 12.5.3 Endangered organisms the loss biodiversity. IUCN Red List (2004) A species that has been categorized as documents the extinction of 784 species in very likely to become extinct is an Endangered the 500 years. species. Endangered (EN), as categorized by the It is estimated that the current rate of International Union for Conservation of Nature biodiversity loss is 100 to 1000 times higher (IUCN) Red List, is the second most severe than the naturally occurring extinction rate conservation status for wild populations in the and is still expected to grow in the future. IUCN's scheme after Critically Endangered This loss of biodiversity has a immense (CR). impact on plant animal and human life. The In 1998 there were1102 animal and 1197 negative effects include dramatic influence on plant species in the IUCN Red List. In 2012, the food web. Even reduction in one species the list features 3079 animal and 2655 plant can adversely affect the entire food chain species as endangered (EN) worldwide. which further leads to an overall reduction in biodiversity. Reduced biodiversity leads 12.5.4 Extinction: to immediate danger for food security by Species is considered extinct when none reducing ecosystem services. of its members are alive anywhere in the world. If individuals of a species remain alive 12.5.2 Hotspots only in or other human controlled Hotspots are areas characterized with high conditions, the species is said to be extinct in concentration of endemic species experiencing the wild. In both of these situations, the species unusual rapid rate of habitat modification loss. would be considered globally extinct. A species Norman Myers defined hot spots as “regions in considered to be locally extinct when it is no that harbour a great diversity of endemic species longer found in an area it once inhabited but is and at the same time, have been significantly still found elsewhere in the wild. impacted and altered by human activities.” In the 450 million years of life on Earth, A hotspot is a region that supports at least there had been 5 mass , which had 1500 endemic vascular plant species (0.5% of eliminated at least 50% of the species of flora the global total) has lost more than 70% of its and fauna on the globe. original vegetation. There are 35 biodiversity The extinction of species is mainly hotspots in the world. India is home to four due to drastic environmental changes and biodiversity hotspots (as per ENVIS). They are population characteristics. a. Himalaya (the entire Indian Himalayan There are three types of Extinctions region) i. Natural extinction is a slow process b. Western Ghats of replacement of existing species with c. Indo-Burma: includes entire North-eastern better adapted species due to changes in India, except Assam and Andaman group of environmental conditions, evolutionary

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TN_GOVT_XII_Zoology_chapter 12.indd 224 25-02-2019 18:45:11 changes, predators and diseases. A small use of natural resources. It was established in population can get extinct sooner than 1948 and located at Gland VD, Switzerland. It is the large population due to inbreeding involved in data gathering and analysis research, depression (less adaptivity and variation). field projects and education on conservation, ii. Mass extinction: The earth has experienced sustainable development and biodiversity. quite a few mass extinctions due to IUCN’s mission is to influence, encourage and environmental catastrophes. A mass assist societies throughout the world to conserve extinction occurred about 225 million years nature and to ensure that any use of natural ago during the Permian, where 90% of shallow resources is equitable and ecologically sustainable. water disappeared. It influences governments and industries through partnerships by providing information iii. Anthropogenic extinctions These are and advice. The organization collects, compiles abetted by human activities like hunting, and publishes the IUCN red list of threatened habitat destruction, over exploitation, species and their conservation status in the urbanization and industrialization. Some world. It plays a vital role in the implementation examples of extinctions are Dodo of of several international conventions on nature Mauritius and Steller’s sea cow of Russia. conservation and biodiversity. seem to be at higher risk of extinction because of habitat destruction. Red Data Book The most serious aspect of the loss fo Red Data book or Red list is a catalogue biodiversity is the extinction of species. The of taxa facing risk of extinction. IUCN – unique information contained in its genetic International Union of Conservation of Nature material (DNA) and the niche it possesses are and Natural Resources, which is renamed as lost forever. WCU – World Conservation Union (Morges Switzerland) maintains the Red Data book. One more species goes extinct... The concept of Red list was mooted in 1963. The purpose of preparation of Red List are: • To create awareness on the degree of threat to biodiversity • Identification and documentation of species at high risk of extinction • Provide global index on declining George the tree snail (Achatinella biodiversity apexfulva) died on January 1, 2019, at • Preparing conservation priorities and help the age of 14. He was the last snail of his in conservation of action species, and is emblematic of the loss of native Hawaiian molluscs. • Information on international agreements on conservation of biological diversity 12.6 IUCN Red list has eight categories of species i) Extinct ii) Extinct in wild iii) Critically The International Union for Conservation Endangered iv) Endangered v) Vulnerable of Nature (IUCN) is an organization working in vi) Lower risk vii) Data deficiency viii) Not the field of nature conservation and sustainable evaluated.

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TN_GOVT_XII_Zoology_chapter 12.indd 225 25-02-2019 18:45:11 12.7 Biodiversity and its i) In-situ conservation conservation ii)Ex-situ conservation The natural resources 12.7.1 In-situ Conservation of the Earth, including air, (Conservation in the natural habitat): water, land, flora and fauna This is the conservation of genetic of natural ecosystems must resources through their protection within be safeguarded for the a natural or manmade ecosystem in which benefit of the present and they occur. It is conservation and protection future generations through careful planning of the whole ecosystem and its biodiversity and management, as appropriate – Principle at all levels in to protect the threatened of the Stockholm Declaration, 1972. species.

The large-scale loss of biodiversity and Maximum protection of biodiversity its global impact makes conservation the hotspots regions with very high levels of need of the hour. species richness. Although all the biodiversity hotspots together cover less than 2 percent of Conservation of biodiversity is protection the earth land area, the number of species they and scientific management of biodiversity harbour is extremely high and protection of so as to maintain it at its optimum level and these hotspots could reduce the ongoing mass. derive sustainable benefits for the present as Protected Areas: well as future generations. It aims to protect These are biogeographical areas where species from extinction and their habitats and biological diversity along with natural and ecosystems from degradation. cultural resources is protected, maintained General strategies in conservation and managed through legal measures. protected areas include national parks, wild • identify and protect all threatened species life sanctuaries, community reserves and • identify and conserve in protected areas biosphere reserves. World Conservation the wild relatives of all the economically monitoring centre has recognized 37,000 important organisms protected areas world-wide. India has about 771 protected areas covering 162099 km2 • identify and protect critical habitats for comprising of National Parks (104), Wild Life feeding, breeding, nursing, resting of each Sanctuaries (544), biosphere reserves (18) species and several sacred groves. • resting, feeding and breeding places of National Parks (NP): the organisms should be identified and It is a natural habitat that is notified by protected the state government to be constituted as a National Park due to its ecological, faunal, • Air, water and soil should be conserved on floral, geomorphological, or zoological priority basis association of importance. No human activity • Wildlife Protection Act should be is permitted inside the national park except implemented the activities permitted by the Chief Wildlife Warden of the state under the conditions given There are two aspects of conservation in CHAPTER IV, of the Wildlife Protection strategies (Fig. 12.3) Act (WPA) 1972 (Table 12.1).

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TN_GOVT_XII_Zoology_chapter 12.indd 226 25-02-2019 18:45:11 and biodiversity and where activities like Project Tiger: The Government of India development, forestry, poaching, hunting, launched the ‘Project Tiger’ in 1973 to grazing and cultivation are not permitted. protect our national animal. From 9 tiger They are large areas of scenic and national reserves since its inception, the Project beauty maintained for scientific educational Tiger coverage has increased to 50 at and recreational use. They are not used present. Project Tiger is an ongoing for commercial extraction of resources. Centrally Sponsored Scheme of the Kaziranga National park is a protected area Ministry of Environment and Forests, for the one Horned Rhinoceros in Assam. providing central assistance to the states for tiger conservation in designated tiger Wild Life Sanctuaries (WLS): reserves. Project Tiger was launched in the Any area other than the area comprised with Jim Corbett National Park, Uttarakhand any reserve forest or the territorial waters can be in1973. The project ensures a viable notified by the State Government to constitute as a population of Bengal tigers in their natural sanctuary if such area is of adequate ecological, faunal, habitats, protecting them from extinction floral, geomorphological, natural or zoological and preserving areas of biological significance. This is for the purpose of protecting, importance as a natural heritage. endangered factual species. Some restricted human activities are allowed inside the Sanctuary area The National Tiger Conservation details of which are given in CHAPTER IV, of the Authority (NTCA) is a statutory body of Wildlife Protection Act (WPA) 1972. Ecoturism is the Ministry, created under the Wildlife permitted, as long as animal life is undistrubed. (Protection) Act, 1972. India holds There are 544 existing wildlife sanctuaries in over half the world’s tiger population. India covering an area of 118,918 km2, which is 3.62 According to the latest tiger census report % of the geographical area of the country (National released on 20th January 2015 by NTCA, Wildlife Database, 2017). the current tiger population is estimated Sanctuaries are tracts of land where wild at 2,212. There are 50 tiger reserves in the animals and fauna can take refuge without being country. hunted or poached. Other activities like collection of forest products, regulated harvesting of timber, Table 12.1 National Parks in Tamil Nadu private ownership of land are permitted. Periyar National Parks Year of wild life sanctuary in Kerala is famous for the Indian District(s) in Tamil Nadu establishment Tiger and Asiatic Elephant (Table 12.2). Guindy NP 1976 Table 12.2 Wild life sanctuaries in Tamil Nadu Gulf of Mannar Ramanathpuram 1980 Prominent WLS Year of Marine NP and Tuticorin Districts Indira Gandhi in Tamil Nadu establishment 1989 Coimbatore (Annamalai) NP Vedanthangal 1936 Chengalpet Mudumalai NP 1990 Nilgiris Lake Birds WLS Mukurthi NP 1990 Nilgiris Mudumalai WLS 1942 Nilgiris Point Calimere There are 104 existing national parks 1967 Nagapattinam in India covering an area of 40,501 km2, WLS Indira Gandhi which is 1.23% of the geographical area of (Annamalai) 1976 Coimbatore the country (National Wildlife Database, WLS Aug. 2018). National Park is an area which is Mundanthurai 1977 Tirunelveli strictly reserved for the betterment of wildlife WLS

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TN_GOVT_XII_Zoology_chapter 12.indd 227 25-02-2019 18:45:11 THE MADRAS CROCODILE BANK TRUST Biosphere Reserve (BR): Biosphere Reserve (BR) is an international The Madras Crocodile Bank Trust and Centre designation by UNESCO for representative for was the brain child of the parts of natural and cultural landscapes legendary Romulus Whitaker and a handful extending over large area of terrestrial or of like-minded conservation visionaries, who coastal/ marine ecosystems or a combination began work on the facility in 1976. It aimed to thereof. BRs are designated to deal with the save India’s dwindling crocodilian population. conservation of biodiversity, economic and The mission is to promote the conservation social development and maintenance of of and amphibians and their habitats associated cultural values. Biosphere Reserves through education, scientific research and are thus special environments for both people capture breeding. The crocodile bank remains a and nature and are living examples of how world leader in the field of frontline conservation human beings and nature can co-exist while and the preservation of natural landscapes. The respecting each other’s needs. The Biosphere Crocodile Bank currently consists of a large Reserve Programme is guided by UNESCO’s park near Chennai and several field Man and Biosphere (MAB) programme, as projects located throughout the subcontinent India is a signatory to the landscape approach reaching as far as the Nicobar Islands. About supported by MAB programme. The scheme half a million people visit the bank every year, called Biosphere Reserve was implemented making it one of the most popular tourist by the Government of India in 1986. There attractions along the East Coast Road. are 18 Biosphere Reserves in the country.

Arignar Anna Zoological Park, Vandalur of installing CCTV Cameras for both visitors Arignar Anna Zoological Park is spread and animal management under the name over an area of 602 hectares. of Reserve of e-Eye. 24 x 7 Animal Live Streaming Forest at Vandalur, Chennai. It is one of the was introduced for the benefit of the visitors largest zoo in South East Asia in terms of for the first time in the world. Vandalur Zoo area. The Zoological Park exhibits different Mobile Application was introduced to provide classes of animals – it has around 2500 wild services to the visitors like facility to book animals of nearly 180 species which includes tickets, Zoo navigation, Animal information Mammals, Birds and Reptiles. 34 years since in text and audio format. Digital payments at its establishment, the Zoological Park has ticket counters are also available. emerged as a successful ex-situ conservation The Zoo school has been involved centre and a centre for many in education and outreach programmes. endangered species like Royal Bengal Tiger, One such successful programme is ‘Zoo Lion Tailed Macaque, Nilgiri Langur, Gray Ambassador’ which is been conducted for Wolf, etc., school children. In the year 2018, more than The Zoo has many attractive features like 400 students were trained and titled as Zoo Butterfly Park, Childrens Park, Walk Through Ambassadors. The Zoo also has a Rescue , Lion & Deer Safari, Forest , Centre which accommodates rescued wild Interpretation centre, etc., which attracts animals and treats them to come out of stress. more than 21 lakh visitors every year. The Source: Director, Arignar Anna Zoological Zoo has strengthened its protection by means Park, Vandalur, Chennai

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TN_GOVT_XII_Zoology_chapter 12.indd 228 25-02-2019 18:45:11 Agasthyamalai (Karnataka - Tamil Nadu - Table 12.3 Difference betweenInsitu and Exsitu Kerala), Nilgiri (Tamil Nadu - Kerala), Gulf of Conservation Mannar (Tamil Nadu) are the BRs notified in Insitu Conservation Exsitu Conservation Tamil Nadu It is the on-site This is a conservation conservation or the strategy which involves Sacred Groves conservation of genetic placing of threatened A sacred grove or sacred woods are any resources in natural animals and plants in populations of plant or special care locations grove of trees that are of special religious animal species. for their protection. importance to a particular culture. Sacred It is the process of It helps in recovering groves feature in various cultures throughout protecting an endangered populations or the world. plant or animal species in preventing their its natural habitat, either extinction under 12.7.2 Ex-Situ Conservation by protecting or restoring simulated conditions It is conservation of selected rare plants/ the habitat itself, or by that closely resemble animals in places outside their natural homes. It defending the species their natural habitats. includes offsite collections and gene banks. from predators. National Parks, Zoological parks and Offsite Collections: Biosphere Reserve, Wild Botanical gardens They are live collections of wild and Life Sanctuaries form are common exsitu domesticated species in Botanical gardens, insitu conservation conservation Zoological parks, Wildlife safari parks, Arborata strategies. programs. (gardens with trees and shrubs). The organisms 12.7.3 Role of WWF and CITES are well maintained for captive breeding World Wild Fund for Nature (WWF) is programmes. As a result, many animals which an international non-governmental charitable have become extinct in the world continue to be trust founded in 1961, with headquarters at maintained in Zoological Parks. As the number Gland, Vaud, Switzerland. It aims at wildness increases in captive breeding, the individuals preservation and the reduction of human impact are selectively released in the wild. In this way on the environment. It was formerly named the the Indian crocodile and gangetic dolphin have World Wildlife Fund. The living planet report is been saved from extinction. being published every two years by WWF since Gene Banks: 1998. The vision of WWF is to conserve nature and Gene banks are a type of biorepository reduce the most pressing threats to the diversity which preserve genetic materials. Seeds of of life on Earth by conserving the world’s most different genetic strains of commercially ecologically important regions, protect and important plants can be stored in long periods restore species and their habitats, strengthen in seed banks, gametes of threatened species local communities’ ability to conserve the natural can be preserved in viable and fertile condition resources they depend upon and to ensure that for long periods using cryopreservation the value of nature is reflected in decision made techniques. by individuals, communities, governments and However, it is not economically feasible businesses. to conserve all biological wealth and all the ecosystems. The number of species required CITES: to be saved from extinction far exceeds the The Convention on International Trade conservation efforts. in Endangered Species (CITES) of wild fauna

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TN_GOVT_XII_Zoology_chapter 12.indd 229 25-02-2019 18:45:11 and flora, also known as the Washington FREEP is conducting pilot eco- Convention, is a multilateral treaty to protect development programmes in the Kalakad- endangered plants and animals. It was drafted from Mundanthurai Tiger Reserve (KMTR) in Tamil a resolution adopted from a meeting of members Nadu. The reserve contains a unique and varied of the IUCN in 1963 and opened for signature in array of flora ranging from thorn and dry 1973. It came into force during July 1975. teak to tropical evergreen, and supports a rich It aims to ensure that international trade in variety of birds and mammals, including tigers, specimens of wild animals and plants should not leopards and elephants.The last tiger refuge in be a threat to the survival of the species in the Tamil Nadu, the KMTR is one of 50 sites covered wild. It accords varying degrees of protection to under the Indian Government’s Project Tiger, a more than 35,0000 species of animals and plants. programme receiving international assistance to enhance tiger habitat. ZOOLOGICAL SURVEY OF INDIA Over 100 villages are now participating in The Zoological Survey of India (ZSI) the KMTR project. Communities and individual was established in 1916 to promote survey, farmers have planted fuelwood and fodder exploration and research leading to the plantations. Some villagers have installed cow advancement in our knowledge of various dung-based gas plants for home fuel needs and aspects of biodiversity of our country. are using fuel-saving pressure cookers and more The objectives of ZSI are: efficient wood-burning stoves (smokeless chulas). • E xploration, Survey, Inventorying and Loans for a wide array of alternative income- Monitoring of faunal diversity in various generating activities such as dairy and poultry states, ecosystems and protected areas of farming, tailoring, coconut leaf weaving, and India. setting up tea and dry goods shops are made • P eriodic review of the status of available. Thus, the eco-development programme threatened and endemic species. at the KMTR is rapidly coming to be seen as a • P reparation of Red Data Book and model for conserving biodiversity through local Fauna of India. participation. • Biological studies on selected important species. CONVENTION ON BIOLOGICAL • M aintenance and Development of DIVERSITY (CBD) National Zoological Collections. The United Nations convention on 12.8 Restoration of Degraded Biological Diversity, known as CBD in Habitat short, was signed by India and 172 other nations on December 29, 1993. The CBD Biodiversity conservation through eco was an attempt to establish an international development – an Indian case study program for conserving and using the The Forestry Research Education and world’s biological resources. This historical Extension Project FREEP (A World Bank treaty recognizes the “sovereign right of Initiative) in India is employing a strategy called nation over their genetic resources” and ‘eco development’ which enlists local commodities considers “appropriate access to genetic in the preservation of biodiversity. The strategy resources.” The treaty also takes into account involves developing alternate resources and sources the “fair and equitable sharing” of benefits of income for those who depend on the protected arising from the use of genetic resources. natural habitat (forest) for their livelihood.

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TN_GOVT_XII_Zoology_chapter 12.indd 230 25-02-2019 18:45:11 12.9 Biodiversity Act (BDA) Summary: The Convention on Biological Diversity Biodiversity is the variety of all life on Earth, (CBD) is a United Nations initiative to protect encompassing genetic, species and ecosystem Biodiversity and encourage the sustainable diversity. Today’s biodiversity is the fruit of billions use of natural resources. The convention was of years of , shaped by natural processes held in 1992 at the ‘Earth Summit’ in Brazil. and, increasingly, by the influence of humans. To India is a signatory of the CBD. The Biological date, about two million species have been identified Diversity Act, 2002 is an Act of the Parliament on Earth. of India for preservation of biological Biodiversity supplies a large number of goods diversity in India, and provides mechanism and services that sustain human life, including for equitable sharing of benefits arising out the provision of food, fuel and building materials; of the use of traditional biological resources purification of air and water; stabilization and and knowledge. The Act was enacted to meet moderation of the earth’s climate; moderation the obligations under Convention on Biological of floods, droughts, temperature extremes and Diversity (CBD), to which India is a party. wind forces; generation and renewal of soil health; The National Biodiversity Authority (NBA) maintenance of genetic resources as inputs to crop was established by the Central Government in varieties and livestock breeds, medicines, and other 2003 to implement India’s Biological Diversity products; and cultural, recreational and aesthetic Act (2002). The NBA is a Statutory Body and it benefits. performs facilitative, regulatory and advisory Over the past few hundred years, biodiversity functions for the Government of India on issues has faced major challenges, including a growing of conservation, sustainable use of biological demand for biological resources caused by resources and fair and equitable sharing of population growth and increased consumption. benefits arising out of the use of biological This increased exploitation of biological resources resources. The Headquarters of the NBA is has resulted in the loss of species at levels currently situated in Chennai. estimated to be 100 times faster than the natural rate of loss prior to significant human intervention. Though many species were lost and new ones Fresh water, wildlife, food and formed, it is likely we will lose all this natural climate are things which are not just ‘Nice wealth in less than two centuries, if the present rate to have’ …. they are ‘Need to have’. These of biodiversity losses persist. are things indispensable for the survival of mankind….. together, we can protect LIFE The biodiversity and its conservation is the on our planet – including our own. important global issue of international concern. Recognition of this problem has made and policy makers to work and develop mechanisms to document, conserve and sustainably use biodiversity. The younger generation should be made to realize the critical state of biodiversity today and volunteer to protect and conserve it, so as to enable the future generations get to enjoy the benefits of Nature.

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TN_GOVT_XII_Zoology_chapter 12.indd 231 25-02-2019 18:45:11 Evaluation b) Both Assertion and Reason are true but 1. Which of the following Reason is not the correct explanation of regio n has maximum Assertion. biodiversity c) Assertion is true , but Reason is false. a) Taiga d) Both Assertion and Reason are false. 10. Define endemism. b) Tropical forest 11. How many hotspots are there in India? c) Temperate rain forest d)Mangroves Name them. 2. Conservation of biodiversity within their 12. What are the three levels of biodiversity? natural habitat is 13. Name the active chemical found in the a) Insitu conservation medicinal plant Rauwolfia vomitoria. What b) Exsitu conservation type of diversity it belongs to? c) In vivo conservation 14. “Amazon forest is considered to be the lungs d) In vitro conservation of the planet”-Justify this statement. 3. Which one of the following is not coming 15. ‘Red data book’-What do you know about it? under insitu conservation 16. Extinction of a keystone species led to loss a) Sanctuaries b) Natural parks of biodiversity – Justify. c) Zoological park d) Biosphere reserve 17. Compare and Contrast the insitu and exsitu 4. Which of the following is considered a conservation. hotspots of biodiversity in India 18. What are called endangered species? Explain a) Western ghats b) Indo-gangetic plain with examples. c) Eastern Himalayas d) A and C 19. Why do we find a decrease in biodiversity 5. The organization which published the red distribution, if we move from the tropics list of species is towards the poles? 20. What are the factors that drive habitat loss? a) WWF b) IUCN I c) ZS d) UNEP 21. Where are biodiversity hotspots normally 6. Who introduced the term biodiversity? located? Why? a) Edward Wilson b) Walter Rosen 22. Why is biodiversity so important and c) Norman Myers d) Alice Norman worthy of protection? 23. Why do animals have greater diversification 7. Which of the following forests is known as than plant diversity? the lungs of the planet earth? 24. Alien species invasion is a threat to endemic a) Tundra forest species – substantiate this statement. b) Rain forest of north east India 25. Mention the major threats to biodiversity c) Taiga forest caused by human activities. Explain. d) Amazon rain forest 26. What is mass extinction? Will you encounter 8. Which one of the following are at high risk one such extinction in the near future. extinction due to habitat destruction Enumerate the steps to be taken to prevent it. a) Mammals b) Birds 27. In north eastern states, the jhum culture is a c) Amphibians d) major threat to biodiversity – substantiate. 9. Assertion: The Environmental conditions 28. List out the various causes for biodiversity of the tropics are favourable for losses. speciation and diversity of organisms. 29. How can we contribute to promote Reason: The climate seasons, temperature, biodiversity conservation? humidity and photoperiod are more or less 30. ‘Stability of a community depends upon its stable and congenial. species diversity’ Justify the statement. a) Both Assertion and Reason are true 31. Write a note on i) Protected areas, ii) Wild and Reason explains Assertion correctly. life sanctuaries, iii) WWF.

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TN_GOVT_XII_Zoology_chapter 12.indd 232 25-02-2019 18:45:11 Concept Map

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233 Biodiversity and its conservation

TN_GOVT_XII_Zoology_chapter 12.indd 233 25-02-2019 18:45:11 ICT CORNER BIO DIVERSITY AND ITS CONSERVATION

Let us go out for an virtual exhibition, to know about 30 endangered animals.

Procedure : Step -1: Type the URL or scan the QR code to open the activity page. Click “Explore the exhibition” to start the exhibition. Step -2: Find the species name below the fi gure (Ex: Helmeted Hornbill). Find a grey dot right next to the name. Click the same to know about its extinction. Step -3: Click “<” on the left top of this page to play a video about the same species. Click “x” to run to the homepage. Step – 4 : On the left “ top fi rst” option to load all the species. Middle square in a circle is for slide show of all the species. Step -5: On the right of the page, fi nd ^ and down button to move on from one to the next.

Step 1 Step 2 Step 3

Step 4

BIO DIVERSITY AND ITS CONSERVATION URL: http://www.species-in-pieces.com/

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