Aspecies that is not native to a particular region

A species that is not native to a particular region is called an invasive species.

Explanation:

In ecology, invasive species can be described as species which are introduced into an environment. These species are not native to the environment.

Introduction of invasive species in an environment can destroy a stable ecosystem. The invasive species will compete for resources like food, shelter, water etc. They might cause the extinction of the species on which they start feeding.  They might fight with predators feeding on the same prey.

equal distribution i think.