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Why Doesn’t An Octopus Have Bones? Octopus Science Experiment

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If there is one thing that is a lot of fun to try when doing ocean science experiments, it is to learn about ocean creatures! Today, we are doing a fun octopus science experiment and learning why an octopus doesn’t have bones!

This easy ocean science experiment will show kids what would happen if an octopus had bones.

Keep reading to get to the directions for this octopus experiment but first, learn a bit more about the octopus and make sure you have everything you need to do this experiment!

This octopus experiment will show kids the scientific method and help them learn why an octopus has a soft body.

What is An Octopus?

An octopus is a sea creature that has eight arms, round heads, and soft bodies. They are most often found in warm, tropical waters.

Octopuses are in the class Cephalopoda along with  squids, nautiloids. and cuttlefish.

Why Doesn’t an Octopus Have Bones?

We don’t know exactly why an octopus doesn’t have bones, except that it evolved that way. Scientists believe that once, the octopus had a shell like sea snails and some other ocean creatures. But over time, it evolved away from having a shell.

Today, the octopus uses it’s soft body to search for prey, hide from predators, and fit into tight spaces.

Octopus Science Experiment Lesson Plan

You can get the complete 17-page lesson plan and customized worksheets for this science experiment in the Jarring Science Club! Your first month is just $5!

Click the image below to learn more.

Octopus Science Experiment Hypothesis

Before getting starting with this experiment, kids should make a hypothesis on why they think an octopus has a soft body. They should also make predictions on whether their octopus will be able to fit through a small hole with and without bones.

Octopus Experiment Supplies

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How to Do the Octopus Science Experiment

To do this experiment, first cut a one-inch hole into the center of a paper plate. Position that over your jar.

Tape in place, if necessary.

Next, make your octopus model and test your variables!

Find out why an octopus doesn't have any bones in this easy octopus science experiment!

Variation 1: How to Make an Octopus Model

Draw your octopus body onto the plastic baggie with a permanent marker. You can freehand it, or use our included template.

Add about a tablespoon of instant snow powder to your baggie.

Fill the bag halfway with water. Add some food coloring.

If the bag is too liquidy, you can add a bit more instant snow powder.

octopus bag experiment

Seal the bag tightly and remove excess air.

Feed the octopus bag through the hole.

Variation 2: Making an Octopus with Bones

Remove the octopus from the bag and add some toothpicks to the bag to represent bones. Try to feed the octopus through the hole again.

It’s much harder or even impossible with the bones!

octopus with bones octopus science project

Octopus Experiment Conclusion

We found that when we gave our octopus bones, it could no longer fit through a small hole. If an octopus had bones, it wouldn’t be nearly as flexible or versitile as it is in the wild.

This could cause the octopus to have a harder time finding food, and a harder time evading predetors.

More Octopus Activities for Kids

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Paper plate octopus craft

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