Biogeographical Evolution in India

Abstract

Earlier discussions on the biogeography of India generally seem to consider the distribution of plants and animals, the floristic and faunistic affinities and compositions and other biogeographical characters as largely static features and also unrelated to the profound and continual changes in the location, size, configuration, topography and drainage patterns of the region. This has unfortunately resulted in considerable confusion and led to untenable conclusions and curious contradictions. The distribution of plants and animals is, however, a dynamic phenomena and embraces the whole history of movements of the flora and fauna, including both gain and loss of the entire biogeographical area. This area is continually undergoing slow but complex changes, increasing in size in some parts, decreasing in size in others, shifting as a whole and coming into contact with other areas or becoming separated from them, breaking up into smaller and isolated patches or also coalescing into larger and more complex units. The present-day biogeographical characters have been derived as a result of gradual and continuous modification of past ones, which in their turn were modifications of still earlier characters. The composition, ecological characters, affinities of the flora and fauna and the distributional patterns of the plants and animals are, therefore, continually changing; we refer to these changes as biogeographical evolution.