Succession
Primary Succession: Flooding happens often in the rainforest, stripping away top soil. Which, contains minerals and nutrients plants need to grow. And if it's stripped away and no plants grow, animals must move to find food. But, eventually, the enviroment will start to grow and form into the rainforest it used to be.
Secondary Succession: Farmers in the rainforest cut down large areas of trees to grow their crops and after a few years the soil becomes infertile. After the farmer moves, secondary succession sets in fertilizing the soil and growing small plants and trees again until the forest, after hundreds of years, grows back.