EN
For a long time, islands have served as the focal point for the studies of numerous researchers, who have been treating them as research laboratories. Their closed-off worlds created by the significant water barrier have caused their evolution to progress differently than on continental land. The isolation has produced endemism, relicts, and ecological niches, which made the islands very sensitive to the external hazards related to the introduction of foreign species. The world 's history is full of examples of such ecological catastrophes and scientific history contains numerous descriptions of them. If the entire animate nature - the flora and the fauna - was endangered, why would the islanders have it any different? Meanwhile, there is much less information concerning the fates of the isolated island communities, which experienced just as dramatic effects resulting from their contacts with foreign arrivals. This study aims to present such relatively recent episodes in the world's history. The article contains fragments and supplements of the thesis previously proposed in M. Jędrusik's book entitled "Wyspy tropikalne. W poszukiwaniu dobrobytu (Tropical Islands. In Search of Prosperity)" (2005). The presented examples from various islands in Oceania confirm the dramatic effects of contacts between the natives and the migrants as well as the diverse resistance of various island populations, which depend on the historical population density of the given regions. It should be noted that limited demographic potential caused more difficulties to the rebuilding of the population than on the continents, thus considerably limiting the development of the territories experiencing this effect. However, the main cause of this hecatomb did not arise from the bad intentions of the arrivals, but the lack of biological immunity among the islanders. The predominantly white arrivals physically destroyed the erstwhile world of the natives, which was sometimes rather erroneously perceived as a distant paradise. The physical barrier between the islands and the continents - the ocean - may be still there, but these contacts made the "immune" endemism of the islanders disappear. Could this have been one of the first symptoms of globalisation?