Starfish Can Squeeze Objects Through Their Skin

posted: 06/16/15
by: Discovery.com Staff
A starfish squeezes a foreign body through its arm tip.
University of Southern Denmark

How does a starfish respond when researchers inject an unwanted research tag into its body? By literally squeezing the tag out through its skin, according to biology students from University of Southern Denmark.

The two students were tasked with tagging several starfish with small tags that allow researchers to identify each individual specimen, a seemingly simple task.

The starfish, however, had a different plan.

"Every time we put a tag into a starfish, they rid themselves of the tag within a few days. It came out directly through the skin; the starfish simply pushed it out through the skin at the end of one arm and then went on as if nothing had happened", the students explained in a news release.

It's not uncommon for organisms to rid themselves of unwanted objects: think of human skin slowly pushing out a splinter. The starfish tags, however, were embedded much more deeply than a common splinter. What's more, the starfish didn't eject the tag via the hole into which it was inserted -- instead, they let the tag travel through their body, before eventually ejecting it through the tip of their arm.

Click here for more information from the University of Southern Denmark

Learn more about starfish:

show more details
Starfish Everywhere

About the blog:
DSCOVRD: The best of the web, covering space, technology, wildlife and more!
More on