The Late Cretaceous terrestrial ecosystems are of worldwide interest due to their proximity to the K/T mass extinction event. During this period the southern Europe (including Transylvania, in Romania) became an archipelago. The landmass of actual Transylvania was inhabited by dwarf dinosaurs. The main topic of this project concerns the latest Cretaceous (Maastrichtian) terrestrial vertebrates from Romania (the „Hațeg Island”) and their specific adaptation to an insular but yet complex environment. The starting point relies on two possible scenarios for the territory of present day Transylvania in Late Cretaceous: a) it was a single and isolated island, or b) it formed an archipelago composed of more or less inter-connected islands? The chosen approach influences the subsequent investigation on paleogeography, morphology and behavior of the vertebrates living in the latest Cretaceous. A complex geological investigation of the „Hațeg Island”, which includes paleontological, stratigraphical, sedimentological and mineralogical studies, will provide insights into the paleoenvironmental reconstructions of the region. Additionally, the knowledge on the Romanian multituberculates (i.e postcranial anatomy, systematic, behavior, origin a.o.) as well as other inhabitants of this terrestrial ecosystem and their endemic evolution will be improved. Mineralogical studies (microscopy, X-ray diffraction, scanning electron microscopy and chemistry) will include not only the sediments but also the geochemical diagenetic profiles of fossil bones. Field work will include the already known Late Cretaceous outcrops from the Transylvanian, Hațeg and the Rusca Montană basins, respectively, and the exploration of new localities. The new material, corroborated with the integrated studies will bring new insights into the landscape, the climatic conditions and the sedimentary constraints in this area.