Its first object was to collect information about plant and animal distribution, and to identify distinct patterns. Phytogeographers and zoogeographers have each divided the terrestrial world into major regions, generally continents or groups of continents considered to possess a characteristic flora or fauna. These two sets of regions do not have precisely the same boundaries. The faunal system based on the divisions proposed by A. R. wallace and P. L. Sclater is probably the best known. The Nearctic and Palearctic regions are sometimes combined to form the Holarctic.
Geographical isolation can also influence evolution.
The theory of island biogeography is an important concept in ecology , and postulates that the number of species in any isolated community is determined by the balance between the rate of arrival of new species, and the rate of extinction of existing ones. Ecology Penguin Dictionary of Sociology 2. The Penguin Dictionary of Psychology 3. Ecology Bloomsbury Thematic Dictionary of Quotations 4. Ecology Bloomsbury Guide to Human Thought 5.