After an extreme disturbance, what kind of organisms move into the area first?

1.       Extreme disturbance refers to circumstances that strike in our environment like flood, fire, volcanic eruption, earthquake, storm, and more.
Now, what are those organisms that took over after this great disturbance?
These extreme disturbances may cause great destruction in our ecosystem. However, after these disturbances come new lives. Plants and animal species started to start over again and form new conditions. Plants will start growing and create another structure in our ecosystem. Animal species will start forming a new group and start a new life in our ecosystem.

Spherical shaped cell might increase the surface area and decrease the volume.