The biogeographic regions are schemes of organism distribution patterns on Earth's surface.

The systems of biogeographical regions started with Augustin de Candolle in 1820. In his study Essai Elementaire de Geographie Botanique he was very interested in documenting the nature and floral composition, also known as biomes. He was the first author to define endemic areas.

It was only after the acceptance of Darwin's theory of evolution that Adolf Engler associated the development of different floras to different regions of the world. His studies on biogeographical regions were based on de Candolle´s climatic and physiological studies.

• Engler´s Biogeographical Regions - 1879
  • Arcto-Tertiary Realm: the temperate and cold regions of the northern hemisphere.
  • Palaetropical Realm: the old world tropics, extending from Africa to northern Australia.
  • Neotropical Realm: most of Central and South America.
  • "Ancient ocean" Realm: costal Chile, Tierra del Fuego, the Cape region and south coast of South Africa, most of Australia, Tasmania, the South Island of New Zealand, and the islands in the southernmost Atlantic, Indian and Pacific Oceans.

In 1908, Diels placed New Zealand in the Palaetropical Realm and subdivided the "Ancient ocean" Realm in four Realms:

• • Antarctic Realm: southern South America and the islands lying at high southern latitudes in the Atlantic and Indian Oceans.
  • Cape Realm
  • Australian Realm

Nineteenth-century zoologists also contributed to the biogeographical schemes. Philip Sclater recognized six regions in 1858 based on passerine bird distributions. Alfred Russel Wallace introduced biogeographical regions based on mammal distributions, and these remain in acceptance by the scientific community.

• Wallace's Biogeographical Regions - 1876
  • Palaearctic Region: temperate Eurasia.
  • Ethiopian: Africa, south of the Tropic of Cancer.
  • Oriental: Tropical Asia, including the adjacent tropical Greater Sunda Islands.
  • Australian: including New Guinea and adjacent islands.
  • Nearctic: North America south to central Mexico.
  • Neotropical: South America and central America as far north as central America.

Biogeography