Biotic gradients in the Oligo/Miocene Western Indopacific

During the Late Oligocene and Early Miocene (~28 to 16 Ma before present) the circumtropical Tethys Ocean, which has persisted since the Permian-Triassic periods became disrupted due to the collision between the African and Eurasian continents. This disruption caused major changes in the distribution and evolution of marine and terrestrial biota. The reorganization of habitats and current patters caused a major shift in the shallow marine biota. The ancestral marine fauna of the western Indopacific Region, which had strong affinities to that of the Mediterranean area during the Late Cretaceous and Palaeogene, widely changed. This change was caused both by local evolution of biota from the surviving stock and by immigration. This process (the "Terminal Tethyan Event") had a major influence on the Neogene biogeography of both the Indopacific and the Mediterranean. Contrary to the Mediterranean, which has been in focus of palaeontological and biogeographical research for more than 200 years, the Western Indopacific is comparatively poorly studied. The focus of this project is to document the changes of shallow marine biota associated with this palaeogeographic reorganization. Biota which will be utilized in this study are gastropods, bivalves, echinoids, corals, larger foraminifera and coralline algae. These groups are known to preserve data viable for palaeobiogeographic reconstruction. Due to the complex taxonomy of these organisms several international projects and specialists from different research institutions will be involved in this study. Key-areas for the reconstruction of the biotic evolution of the early Western Indopacific are in Iran, Oman, Pakistan and along the East African Coast (Tanzania). The final results will provide a distributional pattern for the studied fossil groups along the northern and western coasts of the Western Indian Ocean. As indicated by the recent situation, biotic gradients due to climatic and oceanographic parameters are to be expected. These could help to develop a better understanding of the paleo- water current system in this region as well will shed light on the global climatic evolution during this time interval. This information is vital for the understanding of the processes which led to the formation of today`s largest and most diverse biogeographic entity - the Indopacific.

During the Late Oligocene and Early Miocene (~28 to 16 Ma before present) the circumtropical Tethys Ocean, which has persisted since the Permian-Triassic periods became disrupted due to the collision between the African and Eurasian continents. This disruption caused major changes in the distribution and evolution of marine and terrestrial biota. The reorganization of habitats and current patters caused a major shift in the shallow marine biota. The ancestral marine fauna of the western Indopacific Region, which had strong affinities to that of the Mediterranean area during the Late Cretaceous and Palaeogene, widely changed. This change was caused both by local evolution of biota from the surviving stock and by immigration. This process (the "Terminal Tethyan Event") had a major influence on the Neogene biogeography of both the Indopacific and the Mediterranean. Contrary to the Mediterranean, which has been in focus of palaeontological and biogeographical research for more than 200 years, the Western Indopacific is comparatively poorly studied. The focus of this project is to document the changes of shallow marine biota associated with this palaeogeographic reorganization. Biota which will be utilized in this study are gastropods, bivalves, echinoids, corals, larger foraminifera and coralline algae. These groups are known to preserve data viable for palaeobiogeographic reconstruction. Due to the complex taxonomy of these organisms several international projects and specialists from different research institutions will be involved in this study. Key-areas for the reconstruction of the biotic evolution of the early Western Indopacific are in Iran, Oman, Pakistan and along the East African Coast (Tanzania). The final results will provide a distributional pattern for the studied fossil groups along the northern and western coasts of the Western Indian Ocean. As indicated by the recent situation, biotic gradients due to climatic and oceanographic parameters are to be expected. These could help to develop a better understanding of the paleo-water current system in this region as well will shed light on the global climatic evolution during this time interval. This information is vital for the understanding of the processes which led to the formation of today`s largest and most diverse biogeographic entity - the Indopacific.