Biogeography and stratigraphy of the Mio-Pleistocene mammals of Sardinia and the 
description of some fossils

The Mio-Plio-Pleistocene faunal succession of Sardinia is discussed in the context of paleogeography and stratigraphy. Some material of a particular stratigraphic or taxonomic interest is described. The name Sus sondaari is introduced to replace the preoccupied name Sus nanus. Sardinia may have become an island during the Late Oligocene. Some of the Early Miocene taxa on Sardinia may have survived there from the time when Sardinia was still connected with the main land, others arrived later to the island. Part of these taxa survived till the Late Miocene, when Sardinia (and Corsica) became connected to the island of Tuscany. At this moment faunal exchange occurred between these areas. Some of the taxa known from the Baccinello area may have come from Sardinia. During the Messinian, Sardinia became connected to the mainland again, the endemic fauna went largely or completely extinct and a balanced fauna entered. During the earliest Pliocene Sardinia (and Corsica) became isolated again and an endemic fauna was formed. Possibly only once, at the beginning of the Middle Pleistocene, new elements were introduced. Twice Sardinia changed from mainland to insular conditions. Both times an endemic fauna with reduced diversity evolved from a mainland fauna. This occurred also in other islands. A possible explanation for such a process is that the carrying capacity of an island is insufficient for viable populations of large carnivores. The larger the island, the larger the carnivore that can survive on it. The dog Cynotherium could survive on Sardinia. The absence of large carnivores may lead to increased competition between herbivores, resulting in reduction in species abundance. Only when large carnivores are lacking, certain typical island adaptations, such as low gear locomotion, evolve.