The funky-looking disco clam -- formally Ctenoides ales -- is quite a sight, with its bright orange coloring and groovy tentacles. But what makes the creature truly unique is the electric-like light that lines the clam's lips.
Previously scientists assumed the light was a form of bioluminescence -- a technique used by other animals, such as anglerfish or fireflies, whereby light energy is released via chemical reaction.
But new research by Lindsey Dougherty, a graduate student at the University of California, Berkeley, has shown the disco clam to employ a fine line of silica micro-structures to reflect underwater light.
Using an electron microscope and other precise imaging instruments, Dougherty was able to show exactly how the disco clam's lips keep the party going. On one side is a perfect line of microscopic balls of silica, like sequins. Silica is the primary element in glass and quartz.
"They're almost ideal reflectors in blue-green water environments," said Dougherty, of the sequin-like silica balls.
On the other side of the clam's lips is dark red. Because the wavelengths of red light rarely penetrate far below the surface, the other side of the clam's lips reflect little to no light -- whereas the silica side is perfectly designed to reflect the blue-green wavelengths.
For Dougherty, who's on her way to a Ph.D. at Berkley, the research and subsequent study -- published this week in the Journal of the Royal Society Interface -- is a childhood dream realized.
"I've dived with humpback whales and great white sharks," said Dougherty. "But when I saw the disco clam, I was enamored. I said then, 'I'm going to do a Ph.D. on the disco clam.'"
Disco clams can be found throughout the South Pacific, from Australia to Indonesia, in water 10 to 160 feet deep.
And more than just a mesmerizing sight, the clams' light-reflecting tricks could be adapted for the real world -- possibly as a technique for creating more efficient lighting in dim settings.