The biogeographic and tectonic history of India

Aim To present an up to date account of the Mesozoic history of India and its relationship to the other Gondwana continents and to Eurasia. Location Continents surrounding the Western Indian Ocean. Methods Utilization of recent evidence of continental relationships based upon research in stratigraphy, palaeomagnetism, palaeontology, and contemporary biotas. Results The physical data revealed a sequence of events as India moved northward: (1) India-Madagascar rifted from east Africa 158-160 Ma (million years ago), (2) India-Madagascar from Antarctica c. 130 Ma, (3) India-Seychelles from Madagascar 84-96 Ma, (4) India from Seychelles 65 Ma, (5) India began collision with Eurasia 55-65 Ma and (6) final suturing took place c. 42-55 Ma. However, data from fossil and contemporary faunas indicate that, throughout the late Cretaceous, India maintained exchanges with adjacent lands. There is an absence in the fossil record of peculiar animals and plants that should have evolved, had India undergone an extended period of isolation just before its contact with Eurasia. Main conclusions The depiction of India in late Cretaceous as an isolated continent is in error. Most global palaeomaps, including the most recent one, show India, as it moves northward, following a track far out in the Indian Ocean. But the evidence now indicates that India's journey into northern latitudes cannot have taken place under such isolated circumstances. Although real breaks among the lands were indicated by the physical data, faunal links were maintained by vagile animals that were able to surmount minor marine barriers. India, during its northward journey, remained close to Africa and Madagascar even as it began to contact Eurasia.