Succession
Secondary Succession happens when there is a natural disaster such as a fire or flood. It happens a lot quicker than primary succession because there is soil and a seed bank present. Primary Succession happens when there was no previous plant life or other growth.
This is primary succession, it shows that it all started just as rocks. Then, growth moves to small plants and eventually they began to get bigger and bigger until you have all of the layers of the Tropical Rainforest.
This picture shows Secondary succession, the burning of forests, which will happen a lot faster than Primary succession.