Primary Succession starts out with only rocks. These rocks may be on a newly formed island or they may come from volcanic origin. There aren't any organisms yet.
The Stages of Ecological Succession
Stage 2: Pioneer Species
In the next stage of Primary Succession, lichen and moss start growing in the none to minimal amounts of soil. They are known as primary species. Underneath the lichen and moss, the rocks begin to break down into soil so other plants can also arrive.
Stage 3: Fast-Growing Plants
After the lichen and moss have created enough soil, they start dying out and becoming organic material to enrich the soil. The grasses and weeds start sprouting (fast-growing plants). Secondary Succession starts here.
Stage 4: Small Bushes and Shrubs
Stage 5: Small Trees
Stage 6: Forest Climax
Large Animals (Deer)
After many of the grass and weeds died, they created organic material which decomposed, helping the soil. Now the soil is deep enough to support small bushes and shrubs. The biodiversity is increasing as do the abiotic and biotic factors,
Now the land has lots of grass which is thriving, but now there are some small trees. The soil is quite deep now, able to support the roots of trees. These trees are tall enough the block the sunlight for small shrubs, and these shrubs will soon die out.
The small trees have now grown into tall and large trees. It has become a forest and it is at its climax. After reaching a climax the forest cannot grow anymore due to limiting factors. It is now a balanced ecosystem at homeostasis.