Colonisation (biology)

Colonization comprises the physical arrival of a species in a new area, but also its successful establishment within the local community.

In ecology, it is represented by the symbol λ (lowercase lambda) to denote the long-term intrinsic growth rate of a population.

Accordingly, colonisation and extinction are key components of island biogeography, a theory that has many applications in ecology, such as metapopulations.

Often times species naturally disperse due to physiological adaptations which allows for a higher survival rate of progeny in new ecosystems.

Other times these driving factors are environmentally related, for example global warming, disease, competition, predation.

Diagram showing bacteria growing and forming into a biofilm on a surface
1. Bare rock 2. New species introduced 3. Death and accumulation of top soil 4. New species introduction displacing pioneer species 5. More nutrients and soil accumulation creates opportunities for larger species colonisation
The range of the little egret ( Egretta garzetta ) has expanded since the 20th century, with the species having colonised most of the New World.
Image of the green Iguana that colonized Anguilla.