Grade levels
 8 - 10
 Contains
 12 pages, Canva tutorial
 subjects
 Function of parasites in an ecosystem | Creating future scenarios | Predicting population trends | Identifying stress factors | Creating diagrams | Climate-dependent distribution
 Description
 Two scenarios are simulated to understand the interaction between living beings and nature:
 Fish and seals are infected by an introduced and therefore unknown parasite species and have fallen victim to the stress factor
 The well-known parasite “stomach worm” suddenly disappears forever
 This is followed by a plenary discussion to determine the various scenarios and their consequences. Then, using a diagram showing the stomach worm ecosystem, stress factors for the seal are identified.