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Species diversity varies spatially. It can be characterised not only by some latitudinal and longitudinal gradients but also by numerous core areas, i.e. by restricted territories with cumulated presence of stenochorous (’’endemic’’) species.

Patterns of diversity can be explained by the spatio-temporal dynamics of the processes which i. generate diversity by speciation, ii. reduce diversity by extinction.

A major part of the core areas served as conservation centres of forrested biomes in their regressive phases during the younger Pleistocene. The periodical expansion of the ’’nonforest’’ biomes during the glaciations (e.,O. periglacial tundra and loess steppe) has isolated the forest refugia. On the other hand, the extension of the grassland and desert biomes was restricted by the recurrent inter- and post-glacial spread of wooded biomes.

The Carpathian Basin with a mosaic pattern of forested and open landscapes displayed very intricate dynamics of faunal types during the Quaternary period. Its geographically transitional position resulted in a conspicuous mixture of faunal elements of diverse origin and geographical history. The campartment structure of the vegetation complexes, typical for the Pannonian forest-steppe, has promoted the survival of some strictly localised, relict-like faunal elements. Especially the hilly areas of transitional climatic conditions, surrounding the Pannonian lowland are populated by numerous, biogeographically significant species and communities.