In a new environment colonization of the substrate occurs in sequence hence it is common to see growth in biodiversity of the new ecosystem with time. Ecological succession begins with pioneer plants in primary succession. These pioneer plants break down rocks to soil hence releasing bound nutrients and making them available to higher plants up in the succession line. Therefore, in the beginning, one will find plants such as mos, lichens and annual plants such as grasses. The biodiversity will increase to include shrubs, then plants like trees will eventually appear.
