(a) George, the tree snail (Achatinella apexfulva)
(b) Sudan - Northern white rhinoceros (Ceratotheriurri simum)

(a) Habitat loss / Habitat fragmentation
(b) Lack of food or water source

Royal Bengal Tiger, Lion Tailed Macaque, Nilgiri Langur and Gray Wolf.

Conservation of animals in their natural habitat is called in-site conservation.
E.g., National parks.

(a) Extinct
(b) Endangered
(c) Extinct in wild
(d) Vulnerable

A species is considered extinct when none of its members are alive anywhere in the world. Environmental changes and population characteristics are the two major reason for species extinction.

The number of species per unit area at a specific time is called species richness, which denotes the measure of species diversity.
E.g., Western ghats have more amphibian species than Eastern ghats

More than 70% of species recorded on earth are animals and 22% are planted. This is because the animals have adapted themselves to ensure their survival in changing environments in comparison to plants. Eg. Presence of nervous system helps animals to control and coordinate their body structures. Therefore diversification in animals is more than in plants.

There are three levels of biodiversity are
(1) Genetic diversity
(2) Species diversity and
(3) Community / Ecosystem diversity

The natural resources of the Earth, including air, water, land, flora and fauna of natural ecosystems must be safeguarded for the benefit of the present and future generations through careful planning and management, as appropriate - Principle of the Stockholm Declaration 1972.

(i) Alpha diversity: It is measured by counting the number of taxa (usually species) within a particular area, community or ecosystem.
(ii) Beta diversity: It is species diversity between two adjacent ecosystems and is obtaining by comparing the number of species unique to each of the ecosystem.

Impact of Industrialization on Biodiversity - Comment. Industrialization is a major contributor to climate change and a major threat to biodiversity. Energy drives our industries, which is provided by burning of fossil fuels. This increases the emission of CO₂, a GHG, leading to climate change. Due to large scale deforestation, the emitted CO₂ cannot be absorbed fully, and its concentration in the air increases. Climate change increases land and ocean temperature, changes precipitation patterns and raises the sea level. This inturn results in melting of glaciers, water inundation, less predictability of weather patterns, extreme weather conditions, out break of squalor diseases, migration of animals and loss of trees in forest. Thus, climate change is an imminent danger to the existing biodiversity.

A sacred grove or sacred woods are any grove of trees that are of special religious importance to a particular culture. Sacred groves feature in various cultures throughout the world.

They are live collections of wild and domesticated species in Botanical gardens, Zoological parks, Wildlife safari parks, Arborata (gardens with tree's and shrubs). The organisms are well maintained for captive breeding programmes.

It is a natural habitat that is notified by the state government to be constituted as a National Park due to its ecological, faunal, floral, geomorphological or zoological association of importance. No human activity is permitted inside the national park except the activities permitted by the Chief Wildlife Warden.
Eg: Mudumalia National park in Nilgiris district

Anthropogenic extinctions are abetted by human activities like hunting, habitat destruction, over exploitation, urbanization and industrialization. Some examples of extinctions are Dodo of Mauritius and Steller's sea cow of Russia. Amphibians seem to be at higher risk of extinction because of habitat destruction

It is a catalogue of taxa facing risk of extinction. IUCN maintains the Red Data Book. It has eight categories of species.

The most serious aspect of the loss of biodiversity is the extinction of species. The unique information contained in its genetic material (DNA), and the niche it possesses are lost forever.

The non-native or alien species of organisms are called exotic species. They are introduced unintentionally or deliberately as biological control agents for or other uses.
Eg .Tilapia fish from East African Coast has been introduced into Kerala's inland water for its high productivity.

(i) In shifting cultivation, plots of natural tree vegetation are burnt away and the cleared patches are farmed for 2-3 seasons, after which their fertility reduces to a point where crop production is no longer profitable.
(ii) The farmer then abandons this patch and cuts down a new patch of forest trees elsewhere for crop production. This system is practiced in northeastern regions of India.
(iii) When vast areas are cleared and burnt, it results in loss of forest cover, pollution, and discharge of CO₂ which in turn attributes to a loss of habitat and climate change which has an impact on the faunal diversity of that regions.
(iv) Carrot grass (Parthenium) and lantana introduced into our country have become invasive and caused environmental damage; they pose a threat to the native species of plants in our forests.

(i) The introduction of the Nile Perch into Lake Victoria led to the extinction of more than 200 species of cichlid fish in that lake.
(ii) Introduction of African catfish Clarias gariepinus for aquaculture poses a threat to the indigenous catfishes in indian rivers.

(i) Amazon is a rainforest that covers most of the amazon has in of south America and territory including nations. It represents over half of the planets rain forests and exhibit the largest and the most diversified tropical rain forest.
(ii) It is home to more than 40000 species of plants 3000 of fishes, 1300 of birds, mammals, amphibians, reptiles and more than 125000 invertebrates.
(iii) It is called lungs of the planet earth because its vegetation continuously recycles CO₂ into O₂.

(i) The reasons for the richness of biodiversity the tropics are: Warm tropical regions between the tropics of Cancer and Capricorn on either of equator possess congenial habitats living organisms.
(ii), Environmental conditions of the tropics are favorable not only for special but also for supporting both variety number of organisms. J
(iii) The temperatures vary between 25^o to 35^oC, a range in which most meta activities of living organisms occur ease and efficiency.
(iv)The average rainfall is often more 200 mm per year. .
(v) Climate, seasons, temperature, humid photoperiods are more or less stable encourage both variety and numbers.
(vi) Rich resource and nutrient availability.
(vii)  Rich resource and nutrient availability.

There are three types of Extinctions
i. Natural extinction: It is a slow process of replacement of existing species with better adapted species due to changes in environmental conditions, evolutionary changes, predators and diseases. A small population can get extinct sooner than the large population due to inbreeding depression (less adaptivity and variation)
ii. Mass extinction: The Earth has experienced quite a few mass extinctions due to environmental catastrophes. Amass extinction occurred about 225 million years ago during the Permian, where 90% of shallow water marine invertebrates disappeared .
iii. Anthropogenic extinctions: These are abetted by human activities like hunting, habitat destruction, over exploitation, urbanization and industrialization. Some examples of extinctions are Dodo of Mauritius and Steller's sea cow of Russia. Amphibians seem to be at higher risk of extinction because of habitat destruction. The most serious aspect of the loss of biodiversity is the extinction of species. The unique information contained in its genetic material (DNA) and the niche it possesses are lost forever.

The major functional attributes are:
1. continuity of nutrient cycles or biogeochemical cycles (N₂' C, H₂0, P, S cycles)
2. soil formation, conditioning or maintenance of soil health (fertility) by soil microbial diversity along with the different trophic members
3. increases ecosystem productivity and provide food resources
4. act as water traps, filters, water flow regulators and water purifiers (forest cover and vegetation)
5. climate stability (forests are essential for rainfall, temperature regulation, C0₂ absorption, which in turn regulate the density and type of vegetation)
6. forest resource management and sustainable development

Genetic diversity refers to the differences in genetic make-up (number and types of genes) between distinct species and to the genetic variation within a single species, also covers genetic variation between distinct populations of the same species. Genetic diversity can be measured using a variety of molecular techniques. India has more than 50,000 genetic variants of Paddy and 1000 variants of Mango. Variation of genes of a species increases with diversity in size and habitat. It results in the formation of different races, varieties and subspecies. Rouwolfia vomitaria, a medicinal plant growing in different ranges of the Himalayas shows differences in the potency and concentration of the active ingredient reserpine due to genetic diversity Genetic diversity helps in developing adaptations to changing environmental conditions. Community/Ecosystem diversity is the variety of habitats, biotic communities, and ecological processes in the biosphere. It is the diversity at ecosystem level due to diversity of niches, trophic levels and ecological processes like nutrient cycles, food webs, energy flow and several biotic interactions. India with its alpine meadows, rain forests, mangroves, coral reefs, grass lands and deserts has one of the greatest ecosystem diversity on Earth.

The major causes for biodiversity decline are:
(i) Habitat loss, fragmentation, and destruction (affects about 73% of all species)
(ii) Pollution and pollutants (smog, pesticides, herbicides, oil slicks, GHGs)
(iii) Climate change
(iv) Introduction of alien/exotic, species.
(v) Over exploitation of resources (poaching, indiscriminate cutting of trees, overfishing, hunting, mining).
(vi) Intensive agriculture and aquacultural practices.
(vii) Hybridization between native and nonnative species and loss of native species
(viii) Natural disasters (Tsunami, forest fire, earthquake, volcanoes).
(ix) Industrialization, Urbanization, infrastructure development, Transport - Road and Shipping activity, communication towers, dam construction, unregulated tourism, and monoculture are a common area of specific threats.
(x) Co-extinction.