Final answer:
Ecological succession is the process of a community changing over time. It includes primary and secondary succession, where new or disturbed land is colonized by different species.
Step-by-step explanation:
Ecological succession is the process in which a community changes through time. It can be divided into primary succession, which occurs in an area that has never been colonized before, and secondary succession, which occurs in a previously inhabited area that has been disturbed.
In primary succession, newly exposed or formed land is colonized by living things. Pioneer species, such as certain hearty plants and lichens, establish themselves first, breaking down the substrate and eventually giving way to other species.
In secondary succession, a disturbed part of an ecosystem recovers and is colonized by remnants of the previous community. Over time, there is a sequential change in species until a new community develops.