Animals that roamed the forest also lost their habitats. A volcanic eruption is one event that can change an ecosystem. Floods, droughts, fires, earthquakes, and storms can also change an ecosystem. After a big change, ecosystems usually come back. Organisms may respond to change in one of three ways.
Some organisms respond by adapting.
Adapting means adjusting to a new habitat. Fireweed on Mt. St. Helens adapted by growing through the crust. Some organisms perish. Organisms that perish do not survive. A turtle may survive a fire.