Answer
The earlier species can provide changes to the environment that help the later species establish themselves.
Work Step by Step
This generally describes secondary succession, where one species takes over when another leaves. The example given in this section is the regrowth after a forest fire: the plants that appear first after a forest fire are those that would not be able to grow with the shade and competition of a forest, but can easily grow once the forest has been cleared. Additionally, these plants will be ones which benefit from the burned remains of the previous trees and plants enriching the soil in ways that are helpful to them.
