Even during the Ice Age, the habitats of the Carpathian Basin were characterised by diversity and mosaic pattern, mainly due to its geographical position. Following the movement of the ice sheet, many species of plants with different ecological requirements established themselves in this area, forming a variety of unusual associations.

Animals followed the changing vegetation cover to the Carpathian Basin. As the climate cooled and became drier, species typical of the tundra drew inward from the ice cap in the north, while species typical of the steppes spread into the area from the east and north-east. As the climate warmed, animals that prefer forest and wooded steppe habitats spread, most of which also came from the east, while others came from the south-east.