Ecozone

An ecozone or biogeographic realm is the largest scale biogeographic division of the earth's surface.

These divisions are based on the historic and evolutionary distribution of plants and animals. Ecozones represent large areas of the earth's surface where plants and animals developed in relative isolation over long periods of time, and are separated from one another by geologic features, such as oceans, broad deserts, or high mountain ranges, that formed barriers to plant and animal migration. Ecozones correspond to the floristic kingdoms of botany or zoogeographic regions of mammal zoology.

Ecozones are characterized by the evolutionary history of the plants and animals they contain. As such, they are distinct from biomes, also known as major habitat types, which are divisions of the earth's surface based on life form, or the adaptation of plants and animals to climatic, soil, and other conditions. Biomes are characterized by similar climax vegetation, regardless of the evolutionary lineage of the specific plants and animals. Each ecozone may include a number of different biomes. A tropical forest in Central America, for example, may be similar to one in New Guinea in its vegetation type, but these forests are inhabited by plants and animals with very different evolutionary histories.

The patterns of plant and animal distribution in the world's ecozones was shaped by the process of plate tectonics, which has redistributed the world's land masses over geological history.

The term ecozone, as used here, is a fairly recent development, and other terms, including kingdom, realm, and region, are used by other authorities with the same meaning. J. Schultz uses the term "ecozone" to refer his classification system of biomes.