The author summarizes the outcome of two decades of personal investigation into the dwarfed insular mammals of the Mediterranean. Formerly believed to be the result of a degeneration process following isolation on an island, the dwarfed elephants, hippos and deer are now considered evolutionary adaptations to their insular environment. This adaptation has become visible in the morphology of these animals, which, apart from being dwarfs, distinguish themselves from the mainland parent forms by their shortleggedness and heavy build. The environmental factors responsible for the change are mainly to be sought in the lack of large predators and the subsequent recurrent overpopulation, resulting in malnutrition (as evidenced by osteoporosis in deer bones) and mass starvation. These conditions favour the small specimens that are in need of less food. The increased rate of evolution made possible in this way was reflected, for instance, in six coexisting deer species on Crete. On Sardinia, where the faunal pattern was obviously incongruous, the existence of paleolithic man became evident during excavations in 1982 and 1983, which focussed attention on the history of this island.