1. Any of the major geographical areas into which the planet Earth is divided on the basis of distinct forms of animal life or fauna: One zoogeographical region or "zoogeographical realm" is the Australian region, which includes marsupial and monotreme forms, such as the platypus and the echidnas (spiny anteaters) that are not found elsewhere.
2. Nine such regions exist:

• Palaearctic (Northern Europe and Asia)
• Nearctic (North America, Greenland, etc.)
• Ethiopian (Africa and Arabia)
• Madagascan (east coast of Africa)
• Neotropical (Mexico, Central and South America)
• Oriental (India, Burma, and S.E. Asia west of Wallace's Line)
• Australasian (Australia, New Guinea, and islands S.E. Of Wallace's Line)
• New Zealand (including neighboring islands)
• Polynesian (numerous pacific islands of volcanic origin having no apparent connection with the continents)