The Glacier Sea Rivals
The Glacier Sea Rivals is a Grade 7 science concept from Amplify Science (California) Chapter 3: Indirect Effects in Ecosystems, revealing that Moon Jellies and Walleye Pollock are competitors because both consume zooplankton. This shared resource means changes in Pollock population indirectly affect Jelly population by altering the availability of their common food supply.
Key Concepts
Analyzing the full food web reveals that Moon Jellies and Walleye Pollock are in competition. They both eat zooplankton.
This means any change to the Pollock population will indirectly affect the Jellies by altering the availability of their shared food.
Common Questions
Why are Moon Jellies and Walleye Pollock competitors?
Both Moon Jellies and Walleye Pollock eat zooplankton. Because they depend on the same food resource, they compete for it. When one species increases, it consumes more zooplankton, leaving less for the other.
How does competition create indirect effects in a food web?
When competitors share a food resource, a change in one competitor population affects the food supply, which then indirectly affects the other competitor. This indirect connection is what creates the cascade effects in the food web.
What happens to Moon Jellies when Walleye Pollock populations decrease?
If Pollock populations decrease, they eat less zooplankton, so zooplankton populations increase. More zooplankton means more food for Moon Jellies, allowing their population to grow indirectly.
What do Grade 7 students learn about competition in Amplify Science?
In Chapter 3 of Amplify Science California Grade 7, students identify competitive relationships in the Glacier Sea food web and trace how competition for shared resources creates indirect population effects.