Succession Succession is a gradual development of a community over time. Succession occurs in predictable stages.
Primary Succession When a small community of living things begin to live in an area that did not previously contain plants or animals. 1. This begins when bare rock is exposed and lichens grow on the rock.
Lichen- pioneer species? Grow on bare rock A symbiotic relationship between algae and fungi Slowly breaks down rock by excreting digestive enzymes
Soil Forms 2. The acids in the lichens break down the rock over time and these particles of rock mix with dead lichen to form soil.
Mosses and Organisms 3. After many years, the soil becomes deep enough for mosses to grow. Insects and other organisms begin to live in the mosses and lichens. When they die, the remains add to the soil.
Plant life 4. Over time, the soil layers thicken and the moss is replaced with ferns. These ferns are replaced by grasses and wildflowers. Small shrubs and trees begin growing.
A Forest 5. After hundreds of years, the soil is deep enough to support a forest.
Climax Community A Community that has grown to its full growth is called a Climax Community