Final answer:
Primary succession begins in lifeless areas with the colonization by pioneer species, which facilitate soil formation and pave the way for more complex ecosystems. Over time, ecological community development leads to a mature climax community.
Step-by-step explanation:
Primary succession is an ecological process that begins in an area where no biotic community previously existed. This process is typically observed in places like the newly formed volcanic islands or after glaciers have retreated, leaving bare rock. In such environments, soil formation is the first critical step towards establishing life.
Pioneer species, which include lichens and some hearty plants, are the first to colonize these new areas. They play a pivotal role in primary succession by breaking down the mineral-rich substrate and thus contributing to the soil formation. As these pioneer species grow and eventually die, they leave behind organic material which enriches the developing soil, paving the way for more diverse and complex plant species.
Over time, through a series of stages, the ecological community develops, leading to a more complex habitat that supports a variety of life forms. The sequence in primary succession involves the initial appearance of pioneer species, followed by intermediate species, and culminating in a mature community that reaches an equilibrium state, often referred to as a climax community. As more and more species inhabit the area, they modify the environment, making it habitable for subsequent species which may be less hardy but more competitive.