Fiber optic cables are what carry phone calls and data signals from coast to coast. But because they're made from thin fibers of glass, they aren't very flexible—making them difficult to install and repair. Now, scientists are finding the secrets to improving fiber optics from the ocean depths.
How sea sponges spread the light. I'm Bob Hirshon and this is Science Update.
Deep in the ocean, a sea sponge known as the 'Venus Flower Basket' attracts prey with a crown of glass spindles. Now, scientists hope that studying these spindles will help improve fiber optics.
Joanna Aizenberg is a scientist at Bell Labs in Murray Hill, New Jersey.
We realized that these fibers can conduct light, like telecommunication fibers. And maybe, in fact, this organism is an illuminated glass house of the deep seas.
She and her colleagues tested the spindles and found that they transmitted light and resisted cracking better than synthetic fiber optic cables.
Aizenberg says the team is continuing to study the properties of these fibers, and how the sea sponge makes them at cold temperatures.
The overall idea of this research program is to try to understand how nature forms these wonderful materials. And then learn from that and apply these mechanisms in order to improve the existing techniques, or bring new techniques that will replace current technologies.
I'm Bob Hirshon for AAAS, the Science Society.
Making Sense of the Research
Nowadays, you hear the term "fiber-optic technology" tossed around everywhere. But what exactly does that mean? Well, simply put, a fiber optic cable is a long, thin cable with a core made of very pure glass. That glass can conduct light over long distances. And the light can be coded to transmit information, including telephone conversations, television images, and computer data.
Fiber optic cables that are in use today are fairly strong, but there's room for improvement. Sometimes they're vulnerable to very fine cracks that can disrupt the flow of information. And digging up and replacing fiber optic cables is an expensive and labor-intensive process.
That's why Aizenberg and her colleagues are interested in the Venus Flower Basket. Living up to 1000 meters below the ocean's surface, it can't rely on sunlight to attract prey to its tantalizing glass spindles. So it makes its own light, like an undersea lamp. And while the glass in its spindles isn't quite as pure as commercial fiber optic cable, it works in a similar way, and it's significantly stronger.
Aizenberg says the key to the strength of the sponge cable lies in the structure that surrounds it. In each spindle, the core light fiber is surrounded by concentric shells of glass. The shells of mollusks, like clams and oysters, are structured in a similar way, and they're also very strong. If scientists can figure out how to apply this strength to commercial cable, they could greatly improve on the current technology.
Aizenberg is also interested in copying the sponge's manufacturing process. Today's fiber optic cables have to be manufactured at extremely high temperatures, which means that the energy and equipment cost a lot of money. Figuring out a way to make the cables at the temperature of sea water, like the sponge, could save millions of dollars in the long run.
Incidentally, the sponge doesn't eat everything that comes its way. Most Venus Flower Baskets also serve as a permanent home for a mating pair of shrimp, who live in the protection of its sturdy spindles while the sponge feeds off their waste. That's why Aizenberg calls them "illuminated glass houses of the deep seas."
Now try and answer these questions:
- What are fiber optic cables?
- How do the sea sponge's spindles resemble fiber optic cables? How are they different?
- What lessons do scientists hope to learn from studying the sponges?
- Describe some of the challenges involved in making commercial material from a living model like this one.
- Have you heard of any other materials in nature that were the inspiration for commercial products?
How Fiber Optics Work, from How Stuff Works, provides a comprehensive overview of fiber optic technology.
Sponges: Wonders of the Seas, by the Oceanic Research Group, is a short primer on sea sponges.
Read about Aizenberg's work at the Bell Labs site.