(a) Himalayas
(b) Indian deserts
(c) Trans-Himalayan region
(d) Western ghats.

(a) Tilapia fish (Oreochromis mosambicus)
(b) African Apple snail (Achatinafulica)

Habitat loss, fragmentation and destruction.

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 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

The term biodiversity was coined by Walter Rosen (1986). The levels of biodiversity are Genetic diversity, Species diversity and ecosystem diversity.

Biodiversity as the variability among living organisms from all sources, including terrestrial, marine and other aquatic ecosystems and the ecological complexes of which they are a part. This includes diversity within species, between species and ecosystems of a region.

(a) Extinct
(b) Critically endangered
(c) Vulnerable
(d) Not evaluated.

Natural extinction, mass extinction and anthropogenic extinction

Death of vulture population is attributed to the veterinary medicine Diclofenac, which is responsible for the thinning of the egg shells. This is an example for biodiversity loss by pollution.

Habitat fragmentation is the process where a large, continuous area of habitat is both, reduced in area and divided into two or more fragments.
Eg. Fragmentation of habitats like forest land into crop lands, orchard lands, plantations, urban areas, industrial estates

log S = log C + Z log A
where S = Species richness
A = Area
Z = Slope of the line (regression coefficient)
C = Y-intercept

Community/ecosystem diversity is the variety of habitats, biotic communities and ecological processes in the biosphere.

Species diversity refers to the variety in number and richness of the species in any habitat.

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.