General Information about Flatworms

Read: Getting A Head The First Hunter from the Shape of Life book.

Flatworms live in marine and freshwater habitats, and inside other creatures as parasites.  Read all about flatworms here and more general information here. This is a primer on marine flatworms for K-12 Students. Read about flatworms that live inside the bodies of animals, including humans, causing diseases.

 Flatworms are hermaphroditic—they have both male and female reproductive organs. There are advantages and disadvantages of being hermaphroditic.

Flatworms have more complicated eyes than previously thought. Their eyes only have one type of photoreceptor but they can distinguish different colors. Some even use the mitochondria (which we all have) in some cells in their heads to form lenses to focus light onto their eye spots.

Numerous different types of animals live in caves. But only recently was a cave dwelling freshwater flatworm discovered by Brazilian scientists.  

Planarians can regenerate body parts including growing a new head and brain. When scientists studied the process they found that the planarians have stem cells to make these new body parts. Scientists identified the gene that makes this possible and are investigating how planarians maintain the stem cells that let them regenerate. Read our blog on planarian regeneration.

General Info

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    Book with pencil

Role in Ecosystem

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    Bee with arrows around it

Climate

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    Thermometer and waves

Human Interaction

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    Human next to globe

Paleontology

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    Skull of dinosaur
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    Lesson Plan
    Who Was "Hunter Eve?"
    The paleontological evidence of the first animal to hunt is tiny trails that have been fossilized in rocks. To start this lesson, students will consider the tracks and traces left by modern animals and what they can learn about an animal from its tracks. They then think about which animal might have been the first hunter. The class considers what it takes to be a hunter and what kind of evidence can we use to figure out what was the first hunter. Students write their ideas in their science notebooks and the teacher shares the ideas with the entire class.

    Full Lesson Plan