Definition - What does Pioneer Species mean?
A pioneer species are the first species to colonize bare earth after a disturbance, or when the environment is too harsh to allow for colonization by other species. Their function is to pave the way for more advanced (sub-climax) species and ultimately the optimum species composition (climax species) that an area is able to support.
Safeopedia explains Pioneer Species
Pioneer species are an important component in the process of natural selection. In revegetation projects, pioneer species are generally introduced to enable re-colonisation of the disturbed area by the vegetation and other forms of life that it would otherwise have supported. The process of succession begins with with primitive lichens, which give way to herbaceous plants, fast-growing trees and shrubs and later the type of vegetation that would have been present had the area not been disturbed. As plants colonize the area, insects, birds and animals return, until the full biodiversity has been restored.