Key Idea.
Section 1
Beyond Predator and Prey
In a food web, connections are not always direct. The size of a population can be affected by other populations it does not eat or gets eaten by.
These are called indirect effects. A change in one population can ripple through the web to affect a non-adjacent population.
Section 2
The Chain Reaction
An indirect effect occurs via an intermediary. For example, Population A eats Population B, and Population B eats Population C.
A change in Population A will cause a change in Population B, which will then cause a change in Population C. Thus, A affects C indirectly.
Expand to review the lesson summary and core properties.
Section 1
Beyond Predator and Prey
In a food web, connections are not always direct. The size of a population can be affected by other populations it does not eat or gets eaten by.
These are called indirect effects. A change in one population can ripple through the web to affect a non-adjacent population.
Section 2
The Chain Reaction
An indirect effect occurs via an intermediary. For example, Population A eats Population B, and Population B eats Population C.
A change in Population A will cause a change in Population B, which will then cause a change in Population C. Thus, A affects C indirectly.