Ecological Succession

Ecological Succession

What is ecological succession?

Ecological succession is the process where an ecosystem gradually changes over time, often after a disturbance.

Occurs in an area that has been previously inhabited but was disturbed (like a forest fire)

Secondary Succession

Occurs in a previously uninhabited area (like bare rock)

Primary Succession

There are 2 types of ecological succession

Primary Succession

Primary succession begins in an area without soil. For example, this area could be a new island formed by a volcano or a area of rock uncovered by a melting sheet of ice.


This process occurs over
hundreds of years.

Secondary Succession

Secondary succession takes place in an area where an existing ecosystem has been disturbed. Natural disturbances include fires, tornados, and hurricanes.


This process occurs over
many years as well.

Multiple Choice

What is ecological succession?

• the process where a species becomes extinct

• the process where an ecosystem dies

• the process where an ecosystem gradually changes over time, often after a disturbance.

• the process where a new species is introduced to an existing ecosystem

Multiple Choice

What kind of ecological succession is pictured?

• Primary succession

• Secondary succession

• Tertiary Succession

• Homeostasis

Multiple Choice

What kind of ecological succession is pictured?

• Primary Succession

• Secondary Succession

• Tertiary Succession

• Homeostasis

Multiple Choice

What kind of ecological succession occurs Occurs in an area that has been previously inhabited but was disturbed (like a forest fire)

• Quaternary

• Teritiary

• Secondary

• Primary

Multiple Choice

How many types of ecological succession are there?

• 1

• 2

• 3

• 4

Multiple Choice

What kind of ecological succession occurs Occurs in a previously uninhabited area (like bare rock)

• Quaternary

• Tertiary

• Secondary

• Primary

​Compare the two diagrams.

​Notice that both diagrams start with "pioneer species", then have "intermediate species" and end with "Climax Community"

Pioneer Species

A pioneer species is the first organism to colonize a barren or disturbed area, like lichens on rocks or grasses on newly formed land.

They are critical in starting the process of ecological succession. 

​Lichen on rock

​Grasses on new land (rock)

Intermediate Species

Organisms that colonize an area after the initial pioneer species and before the climax community, often including grasses, shrubs, and smaller trees

Climax Community

The final, stable stage of ecological succession, where a community of plants and animals has reached a balance with its environment

Multiple Choice

What is a pioneer species?

• Organisms that colonize an area after the initial pioneer species and before the climax community

• the first organism to colonize a barren or disturbed area

Multiple Choice

What is a climax community?

• A natural disturbance of an ecosystem

• The first organism to colonize a barren or disturbed area

• The final, stable stage of ecological succession

• Succession that takes place in an area where an existing ecosystem has been disturbed

Multiple Choice

The Los Angeles forest fires have disturbed a previously existing ecosystem, what kind of succession will take place?

• Primary

• Secondary

Multiple Choice

A volcano near Hawaii has erupted and created a new island made entirely of bare rock. What kind of succession will take place?

• Primary

• Secondary

Multiple Choice

A tornado has wiped a flower field clean, only soil remains. What kind of succession will take place?

• Primary

• Secondary