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Patterns of Biodiversity, a) Latitudinal gradients- the diversity of, plants and animals is not uniform, throughout the world and shows uneven, distribution. This distribution pattern is, along the latitudinal gradient in diversity., Species diversity decreases as we move, away from the equator towards the poles., Tropics harbor more species than, temperate or polar areas.Amazonian, Rainforest has the greatest biodiversity on, earth. It has more than 40000 species of, plants, 1,25,000 species of insects, 300, species of fish, 427 of amphibian and 378, of reptiles, 1300 species of birds and 427, of mammals. Various hypothesis has, been proposed regarding this such asa) Speciation is a function of time unlike, temperate regions subjected to frequent, glaciation in past, tropical latitudes have, remained relatively undisturbed for, millions of years and thus had long, evolutionary time for species, diversification., b) Tropical environments unlike temperate, ones are less seasonal and more, constant and predictable which promote, niche specialization and lead to a greater, species diversity., c)There is more solar energy available in

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the tropics which contribute to higher, productivity this in turn contribute, indirectly to greater diversity., b) Species-Area relationships, • Alexander Von Humboldt has observed, that within a region, species richness gets, increased when explored area is, increased, but only up to a limit., • The relationship between species, richness and area for a number of taxa, like angiospermic plants, fresh water, fishes and birds is found to be a, rectangular hyperbola., On logarithmic scale, the relationship is a, straight line described by the equationlog S = log C+Z log A, S means species richness, C= Y- intercept, Z= slope of the line, regression, coefficient., A= area, Biodiversity or biological diversity is the, occurrence of different types of, ecosystems, different species of, organisms and their variant like biotypes,, ecotypes and gene adapted to different, climates and environments of different, regions including their interactions and, processes.This term was coined by

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Edward Wilson.The vast array of species, of micro-organisms, algae, fungi, plants, and animals occurring on the earth either, in the terrestrial or aquatic habitats and, the ecological complexes of which they, are a part comprises biodiversity ., Diversity ranges from macromolecules to, biomes.