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Bamboos comprise the subfamily Bambusoideae distributed in all continents except for Antarctica and Europe. They occupy varied habitats and are sensitive to climate change. They have sporadic flowering and low rates of dispersal, which make them indigenous and characteristic of the continents in which they occur. Plate tectonics have also played an important role in their dispersal. The dependency of various organisms on bamboos as food source and their sensitivity to climate change make bamboos difficult to manage in terms of their sustainable use. Moreover, habitat polymorphism in bamboos poses difficulties when reconstructing their evolutionary ecology, diversification, and biogeography, though molecular phylogenetic data infer their evolution in a warm and mesic environment. We report two new fossil compressions/impressions of bamboo culms, namely Bambusiculmus tirapensis sp. nov. and Bambusiculmus makumensis sp. nov. from the late Oligocene and two new impressions of bamboo leaves, namely Bambusium deomarense sp. nov. and Bambusium arunachalense sp. nov. from the late Miocene to Pliocene sediments of northeast India. The culm fossils reported here represent the earliest records of bamboos from Asia thereby indicating that bamboos probably dispersed to Asia from India after the establishment of land connections between the Indian and Eurasian plates. The Neogene bamboos indicate the diversification of their ecological niche during the Miocene in Asia. The present fossils also reveal their adaptation to a monsoonal climate since the late Oligocene. (C) 2018 Elsevier B.V. All rights reserved.