Dynamics of paleoecosystems in the Bolivian Altiplano during the Andean surrection, from the Middle Miocene (15 Ma) to the present day. The formation of high relief in the Andes allowed the development of high altitude steppes, as we know them today. However, preliminary palaeobotanical data indicate lowland tropical conditions until about 10 Ma. The project in which the thesis is embedded, resolutely multidisciplinary, focuses on a region (Bolivian Altiplano, Corque syncline, Choquecota-Pomata Ayte) and a time interval (Middle Miocene-Actual) that are of major interest from a palaeontological and geodynamic point of view, as they are linked to this phase of intense surrection. The objective of this thesis will therefore be to study the palynology of the Pomata Ayte sedimentary series covering the Neogene and the early Quaternary and to reconstruct the corresponding palaeoenvironments (vegetation changes, climate, palaeoaltitudes) in an ideally constrained geochronological context, thus making it possible to determine the response time of the ecosystems to the uplift as well as the impact of these changes on the vertebrate fauna. These reconstructions are essential for geologists to trace orogenic events and erosion processes, and for climate modellers to improve global climate modelling.