Colonisation (biology)
Colonisation or colonization is the spread and development of an organism in a new area or habitat. 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.
For the same species living closely together, see Colony (biology).
Surrounding theories and applicable process have been introduced below. These include dispersal, colonisation-competition trade off and prominent examples that have been previously studied.
One classic scientific model in biogeography posits that a species must continue to colonize new areas through its life cycle (called a taxon cycle) in order to achieve longevity. Accordingly, colonisation and extinction are key components of island biogeography, a theory that has many applications in ecology, such as metapopulations. Another factor included in this scientific model is the competition-colonisation trade off. This idea goes into the driving factors of colonisation through many species that all share a need to expand.
Scale[edit]
Colonisation occurs on several scales. In the most basic form, as biofilm in the formation of communities of microorganisms on surfaces.[1]
This microbiological colonisation also takes place within each animal or plant and is called microbiome.
In small scales such as colonising new sites, perhaps as a result of environmental change. And on larger scales where a species expands its range to encompass new areas. This can be through a series of small encroachments, such as in woody plant encroachment, or by long-distance dispersal. The term range expansion is also used.[2]
Dispersal[edit]
Dispersion in biology is the dissemination, or scattering, of organisms over periods within a given area or over the Earth. The dispersion of species into new locations can be inspired by many causes. 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. Dispersion of different species can come in many forms. Some prime examples of this is flight of species across long distances, wind dispersal of plant and fungi progeny, long distance of travel in packs, etc.
Use[edit]
The term is generally only used to refer to the spread of a species into new areas by natural means, as opposed to unnatural introduction or translocation by humans, which may lead to invasive species.