Glass Sponge

Associated Smithsonian Expert: Klaus Ruetzler, Ph.D.

Dr. Klaus Ruetzler examines sponges maintained in a running-seawater system at the wet lab in Carrie Bow Cay, Belize.

Photo credit: Molly K. Ryan

Dr. Klaus Ruetzler is a research zoologist and curator of sponges in the Department of Invertebrate Zoology at the Smithsonian National Museum of Natural History. His current research focuses on the diversity and ecology of sponges from submarine caves on the Mesoamerican Barrier Reef of Belize (Central American Caribbean). He is also working on a book describing 40 years of Smithsonian research on this coral reef ecosystem for which he founded the Smithsonian Carrie Bow Marine Field Station in 1972. He grew up in Austria and first became interested in sponges when he explored submarine caves, using self-made scuba gear, in Croatia, Adriatic Sea, where sponges make up most of the colorful fauna. He turned his early observations into a dissertation and earned a doctorate at the University of Vienna. He was hired by the Smithsonian Institution when a position for a sponge specialist became available.

Meet our associated expert

This image was obtained from the Smithsonian Institution. The image or its contents may be protected by international copyright laws.

Make Field Book Cover

Image of Glass Sponge

Create your own field book and fill it with images and object from Q?rius! When you create a field book, you can put this image on its cover.

or Sign up




Add a comment

Be the first to leave a comment!

Tube-shaped glass sponge (Euplectella aspergillum) in a yellow sponge
Courtesy of North Atlantic Stepping Stones Science Party, IFE, URI-IAO; NOAA/OAR/OER

About Glass Sponges (Class Hexatinellida): Senses

Sponges do not have nervous systems, but a glass sponge has a unique set-up that allows it to conduct electrical impulses around its body in response to stimuli from outside. As its body cells divide, they do not separate completely. They remain connected by bridges of cell material, resulting in a mega-cell that looks like a spider web. This web of soft tissue (called a syncytial network) is wrapped around a mineral skeleton for support. When the mega-cell gets stimulated by something outside, an impulse travels rapidly from one part of the sponge to another, across the cell-cell bridges. This function is similar to what our nervous system does, and may allow a glass sponge to respond to signals from its environment.

Scientific diver looking at sponges (Cliona celata)
Courtesy of yann fontana, World Register of Marine Species, CC-BY-NC-SA

About Sponges (Phylum Porifera): Use by Humans

Most bath sponges these days are artificial, but a reminder of when a sponge meant the dried up skeleton of a sea sponge. As long as 4,000 years ago, Greeks were free-diving for sponges in the Mediterranean Sea to sell for bathing. A sponge diver had a dangerous job, facing steep coastlines, sharks, and deep water. Special equipment gradually came into use, starting with a simple rake and advancing during the 1800s to a dive suit with a long tube connected to a boat air supply. The uses of sponges expanded to include cushion stuffing, agricultural fertilizer, scouring pads, and food additives. Modern sponge divers are often sponge researchers (spongologists) with scuba tanks, dive computers, or even submersibles. Research on sponges has allowed us to better understand their value to us. Because sponge cells can tell apart self from non-self, they have served as simple models for study of our immune system. Today, they are mostly used for their pharmacological properties; many sponges contain medicinal compounds.