Flatworms' Role in the Ecosystem

Marine flatworms are mainly carnivores that prey on tiny animals (protozoa, copepods and other worms) or feed on immobile animals such as bryozoans and tunicates. Flatworms play a role in many food chains. Some flatworms are parasites and parasites of all sorts are essential to most food webs and even in some food webs make up the majority of the biomass. But on the other hand, parasitic flatworms can disrupt coral reef ecosystems.

Animals are often used to monitor toxins in the environment. Researchers found that flatworms in estuaries can indicate the health of the ecosystem.

Invasive flatworms are a threat to forest ecosystems in the U.S. These flatworms come into the country on imported garden plants. Read more about it in our Featured Creature on Planarians.

An invasive flatworm from New Guinea has invaded Europe.

General Info

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    Book with pencil

Role in Ecosystem

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    Bee with arrows around it


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    Thermometer and waves

Human Interaction

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    Human next to globe


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    Skull of dinosaur
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    Red orange and pink flatworm
    Lesson Plan
    Flatworms: The First Hunter Questions
    There are three separate lessons here based on questions.A list of questions about the characteristics of flatworms to use after viewing the video Flatworms: The First Hunter.A Shape of Life: The First Hunter worksheet. Students make sketches and write short answers to questions about the amazing world of flatworms. This was created by Rachel Miller from Science from Scratch.A Powerpoint with questions to use while watching the video Flatworms: The First Hunter. 

    Full Lesson Plan