In biogeography, a species is indigenous to a given region or ecosystem if its presence in that region is the result of only natural processes, with no human intervention. The term is equivalent to the concept of native or autochthonous species. Every wild organism has its own natural range of distribution in which it is regarded as indigenous. Outside this native range, a species may be introduced by human activity, either intentionally or unintentionally; it is then referred to as an introduced species within the regions where it was anthropogenically introduced.
The notion of indigeneity is often a blurred concept, as is a function of both time and political boundaries. Seen over long periods of time, plants and animals take part in the constant movement of tectonic plates—species appear and may flourish, endure, or become extinct, and their distribution is rarely static or confined to a particular geographic location.
An indigenous species in a location is not necessarily also endemic to that location. Endemic species are exclusively found in a particular place. An indigenous species may occur in areas other than the one under consideration. The terms endemic and indigenous also do not imply that an organism necessarily first originated or evolved where it is currently found.