What is Endemism?

Endemism describes species that are native to a particular geographic area or continent. Examples of endemism in Australia are the koala and the red kangaroo, both of which are not naturally found anywhere else in the world.

Endemism usually occurs in areas that are isolated in some way. Australia has been isolated from other continents for tens of millions of years, resulting in a high level of endemism. More than 80% of our plant and animal species are not found on any other continent.

Endemism occurs when populations of one species are separated so they cannot interbreed. Both populations continue to breed and evolve separately. In time, it is possible they will become two separate species. This evolution of new species is called speciation.

The factor that causes populations to separate is called an isolating mechanism. Isolating mechanisms can be geographical (for example, changes in sea level or the formation of mountain ranges) or behavioural (for example, a population developing two different mating seasons or behaviours).

Endemism doesn't just occur between continents, it also occurs within them. For example, species can be restricted to large regions such as south-west Australia or tropical Queensland. Endemism can also occur over very small areas, such as on mountain tops or around mound springs. The isolating mechanism in both these cases would be the unsuitable nature of surrounding areas.

Endemism describes species that are native to a particular geographic area or continent. Examples of endemism in Australia are the koala and the red kangaroo, both of which are not naturally found anywhere else in the world.