There are three main ways to divide the Earth’s terrestrial biota: 1) the traditional division into realms justified especially in the tropics and the Southern Hemisphere; the author has proposed to define a realm as an area over 106 km2 and rich in endemic families; 2) latitudinal zonation most feasible on the lowlands of the Nothern Hemisphere; and 3) the division into biomes as a rough generalization embracing zonal and mountain ecosystems for all continents; the author has proposed a division into 12 main biome types.
Keywords: biogeography, biomes, endemic families, realms, zones.