Patterns of regional species richness and endemism in Indian birds: a biogeographical perspective

The heterogeneous geography and climate of India and the associated rich biodiversity have together made it one of the world’s megadiverse countries. The more than 1300 species of birds known within its geographical limits amount to 12% of the world’s avifauna. India’s unique share of the world’s avifauna is, however, less than 0.7%. This is due to the fact that only 75 species are endemic to the country. Moreover, passerine species are unevenly distributed, creating distinct patterns of avifaunal species richness and endemism. Three avifaunal regions based on species richness and endemism are discernable. Passerines play a major role in creating these three avifaunal regions. Regions with relatively poorer avian species richness and lower number of passerines have a higher number of endemics. The intriguing patterns in the species richness and endemism of Indian birds are explained by its biogeographical history and the state of avifaunal development.