Palearctic realm

Both the eastern and westernmost extremes of the Paleartic span into the Western Hemisphere, including Cape Dezhnyov in Chukotka Autonomous Okrug the to the east and Iceland to the west.

In an 1858 paper for the Proceedings of the Linnean Society, British zoologist Philip Sclater first identified six terrestrial zoogeographic realms of the world: Palaearctic, Aethiopian/Afrotropic, Indian/Indomalayan, Australasian, Nearctic, and Neotropical.

The Palearctic realm includes mostly boreal/subarctic-climate and temperate-climate ecoregions, which run across Eurasia from western Europe to the Bering Sea.

The middle altitude foothills of the Himalaya between about 2,000–2,500 m (6,600–8,200 ft) form the boundary between the Palearctic and Indomalaya ecoregions.

China, Korea and Japan are more humid and temperate than adjacent Siberia and Central Asia, and are home to rich temperate coniferous, broadleaf, and mixed forests, which are now mostly limited to mountainous areas, as the densely populated lowlands and river basins have been converted to intensive agricultural and urban use.

In Southeastern Asia, high mountain ranges form tongues of Palearctic flora and fauna in northern Indochina and southern China.

The Holarctic has four other endemic bird families: the divers or loons (Gaviidae), grouse (Tetraoninae), auks (Alcidae), and waxwings (Bombycillidae).

Several large Palearctic animals became extinct from the end of the Pleistocene into historic times, including Irish elk (Megaloceros giganteus), aurochs (Bos primigenius), woolly rhinoceros (Coelodonta antiquitatis), woolly mammoth (Mammuthus primigenius), North African elephant (Loxodonta africana pharaoensis), Chinese elephant (Elephas maximus rubridens), cave bear (Ursus spelaeus), Straight tusked elephant (Palaeoloxodon antiquus) and European lion (Panthera leo europaea).