The evolution and diversification of ancient megathermal angiosperm lineages with Africa-India origins in Asian tropical forests is poorly understood because of the lack of reliable fossils. Our palaeobiogeographical analysis of pollen fossils from Africa and India combined with molecular data and fossil amber records suggest a tropical-African origin of Dipterocarpaceae during the mid-Cretaceous and its dispersal to India during the Late Maastrichtian and Paleocene, leading to range expansion of aseasonal dipterocarps on the Indian Plate. The India-Asia collision further facilitated the dispersal of dipterocarps from India to similar climatic zones in Southeast Asia, which supports their out-of-India migration. The dispersal pathway suggested for Dipterocarpaceae may provide a framework for an alternative biogeographic hypothesis for several megathermal angiosperm families that are presently widely distributed in Southeast Asia.

Sunda region was the scene of widespread rifting during the mid-Cenozoic, resulting in the development of numerous large lakefilled rifts, analogous in scale to the rift valley system of East Africa. The Tonle Sap in Cambodia forms the closest modern analogue for these lakes in the Southeast Asian region. Many of the palaeolakes were long lived, continuing uninterrupted as open lakes for several millions of years during the Oligocene. Smaller rift systems infilled with fluvial sediments, but the majority remained as lakes, and with Late Oligocene subsidence, were transformed by brackish, and in the earliest Miocene, by marine incursion, into large inland seas. These seas reached their greatest extent at the time of the mid Miocene thermal maximum. This paper describes the development and eventual demise of these lakes following marine transgression, and, based on their rich content of pollen and spores, illustrates the variety of fresh and brackish water swamp communities which developed around their margins. The marginal swamps can be divided into: i) seasonally inundated swamps, mainly during the Oligocene, characterised by Barringtonia, Lagerstroemia and grasses/sedges; ii) fern swamps from the Late Oligocene onward; iii) alluvial swamps, often characterised by Pandanus; and iv) peat swamps. The latter can be differentiated into kerapah peat swamps, first occurring during the Oligocene, and basinal peat swamps, becoming widespread from the Early Miocene onward.

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Aim To determine the vegetation and landscape experienced by Homo erectus populations which first inhabited Java. Location Perning, near Mojokerto, East Java, the 1936 discovery locality of a fossil child's skull widely attributed to H. erectus, and laterally equivalent sediments at Jetis. Taxon Terrestrial, mangrove and aquatic plants. Methods A comprehensive suite of samples was collected at close spacing through a coastal sedimentary succession analysed concurrently for its depositional origins. The section traversed particularly informative marine, delta front and delta plain deposits, including the bonebed in which the H. erectus was discovered. Results Rich palynomorph recovery indicative of mangroves was obtained in the mud‐dominated marine Mollusk Member II at the base of the analysed section. The overlying deltaic strata are characterized by grass pollen and phytoliths, while still retaining mangrove and wetland signals in key samples near the level of the H. erectus bed. Main conclusion The vertical stratigraphic series of facies in the Perning and adjacent Jetis sections indicates a landscape with four potential Homo habitats: muddy deltas with widespread Nypa swamps; a poorly vegetated sandy delta; extensive open savanna grasslands in the lowlands up river of the delta; and volcanoes in the upper reaches of the catchment with perhumid montane podocarp and broad‐leaf forests and probable open fire‐climax Casuarina junghuhniana forest. Palynological data support an Early Pleistocene geological age for Mojokerto H. erectus at about 1.43 Myr.

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