Skip to main content
Email Print Share

"Goby Dessert" -- The Discovery Files

The Discovery Files
Audio Play Audio
The Discovery Files podcast is available through iTunes or you can add the RSS feed to your podcast receiver. You can also access the series via AudioNow® by calling 641-552-8180 on any telephone.

Scientists at the Georgia Institute of Technology have found evidence that when corals are under attack by toxic seaweed they do what anyone might do when threatened--they call for help.

Credit: NSF/Karson Productions

Audio Transcript:

(Sound effect: dinner bell becomes muted) Silent dinner bell.

I'm Bob Karson with the discovery files--new advances in science and engineering from the National Science Foundation.

(Sound effect: underwater voice on p.a. speaker) "Attention algae eaters we have a seaweed special on coral five, all you can eat as long as it lasts."

When coral reefs are in danger from reef-killing algae--or seaweed -- wouldn't it be wonderful if they could put the word out and get help from algae-eating fish? Well, they can, according to scientists at Georgia Tech. Through a chemical signal, one that masses throngs of hungry one-inch long fish called gobies to swallow up or remove the toxic seaweed. It's a symbiotic relationship. The gobies gobble and the coral provides safe haven.

The research studied goby behavior, when an especially toxic seaweed, is introduced onto the coral. Within minutes of contact it was "go, go gobies." The little munchers defended their home among the coral by going right to the site of the offending seaweed and nipping it in the bud. By testing water samples, the scientists determined it was not the presence of the seaweed that alerted the gobies, but a chemical odor released by the coral as a signal.

This new information really demonstrates the complexity of coral reef systems. Scientists say it may be a key to understanding the resilience of some coral species.

The fish take care of the coral--the coral take care of the fish. Should we think of seaweed as the "goby dessert?" (Sound effect: rimshot) Sorry.

"The discovery files" covers projects funded by the government's national science foundation. Federally sponsored research--brought to you, by you! Learn more at or on our podcast.

General Restrictions:
Images and other media in the National Science Foundation Multimedia Gallery are available for use in print and electronic material by NSF employees, members of the media, university staff, teachers and the general public. All media in the gallery are intended for personal, educational and nonprofit/non-commercial use only.

Images credited to the National Science Foundation, a federal agency, are in the public domain. The images were created by employees of the United States Government as part of their official duties or prepared by contractors as "works for hire" for NSF. You may freely use NSF-credited images and, at your discretion, credit NSF with a "Courtesy: National Science Foundation" notation. Additional information about general usage can be found in Conditions.

MP3 icon
NSF podcasts are in mp3 format for easy download to desktop and laptops, as well as mobile devices capable of playing them.