Image: Rhett A. Butler

Quiz time! See if you can answer these sea cucumber questions …

1. Who appeared on Earth first, sea cucumbers or dinosaurs?

You lose, dinosaurs. The oldest known sea cucumber fossils are about 400 million years old. The first known dinosaur fossils are only about 243 million years old.

2. True or False: Sea cucumbers are actual vegetables that have learned how to swim.

False! Sea cucumbers superficially resemble the vegetables they are named after, but they are 100% animal and 0% plant. They are members of the phylum Echinodermata, the same group as sea stars and sea urchins.

3. True or False: Sea cucumbers like cucumbers in their salad.

False! Sea cucumbers are detritivores. They eat bits of dead plants and animals in the open ocean or in the sand on the ocean bottom.  They play a very important ecological role by breaking down the dead stuff in the ocean and recycling nutrients back into the food chain.

4. If a sea cucumber has a stomach ache, how does it make itself feel better?

Some sea cucumber species practice evisceration, which means that they spit out their internal organs, either through their mouths or their cloacas (behinds). They will then regenerate their internal organs. This behavior may help relieve them of parasites. 

Some sea cucumber species have special organs called Cuvierian tubules that are sticky like a Spider-Man web and shot out of their cloacas at predators. This is a defense against being eaten. The Cuvierian tubules will regrow in weeks.

This sea cucumber is ejecting Cuvierian tubules:

Rpillon, CC BY-SA 3.0, via Wikimedia Commons

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