Number of identified species in the World

Biodiversity is the occurrence of different types of ecosystems, different species of organisms with the whole range of their variants (biotypes) and genes adapted to different climates, environments along with their interactions and processes. The concept of biodiversity first appeared in 1980. Biological diversity differs from place to place. It is so because environmental conditions of the area as well as the range of tolerance of the species determine whether or not a particular species survive in that area.

The most interesting aspect of biodiversity is that more than 70% of all species are animals while plants account for only 22%. Amongst animals, insects are the most numerous (about 70%). The number of fungi species in the world is more than the combined total of the species of fishes, amphibians, reptiles and mammals. New species are being discovered faster than 15000/year due to projects like Global Biodiversity Information Facility and Species 2000.

                                    

	Group	Number of species
1	Viruses	1,550
2	Bacteria/ Cyanobacteria	4,000
3	Algae	40,000
4	Fungi	72,000
5	Protozoa	40,000
6	Higher Plants	2,70,000
7	Nematodes and Worms	25,000
8	Molluscs	70,000
9	Crustaceans	43,000
10	Insects	10,25,000
11	Amphibians	4,780
12	Fish	26,959
13	Reptiles	7,150
14	Birds	9,700
15	Mammals	4,650
16	Others	1,10,000