Endemism is the state of a species only being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsewhere. For example, the Cape sugarbird is found exclusively in southwestern South Africa and is therefore said to be endemic to that particular part of the world. An endemic species can also be referred to as an endemism or, in scientific literature, as an endemite.

In biogeography, a cosmopolitan distribution is the range of a taxon that extends across all of the world, in appropriate habitats; most cosmopolitan species are known to be highly adaptable to a range of climatic and environmental conditions, though this is not always so. Killer whales (orcas) are among the most well-known cosmopolitan species on the planet, as they maintain several different resident and transient (migratory) populations in every major oceanic body on Earth, from the Arctic Circle to Antarctica and every coastal and open-water region in-between. Such a taxon is said to have a cosmopolitan distribution, or exhibit cosmopolitanism, as a species; another example, the rock dove, in addition to having been bred domestically for centuries, now occurs in most urban areas across the world.