A graduate student from the University of Berkeley, Calif. discovered the secret behind a clam's ability to produce disco-like lights.
Lindsey Dougherty found that clams' amazing light shows weren't a result of bioluminescence, as most experts have believed in the past. Instead, the clams produced these lights because their mantle lip was reflective on either side. Once the clam moved its lip, a mirror-like part acted upon the light and reflected it in different colors.
Dougherty's interest in this research started when she first saw disco clams on a diving trip.
"I've dived with humpback whales and great white sharks," shared Dougherty in a university news release. "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.'"
Dougherty's research determined that the interior of the clam's lip contains millions of silica spheres. These silica spheres whose diameter only measures 340 nanometers served as reflectors of the blue light that penetrates the water at that level.
As the clam moved its lip, it created a light show similar to a disco ball. The outer part of the lip, which did not have nanosphere, absorbed the blue light. This created a contrast between the two sides of the lip which made the light show more amazing.
Dougherty utilized high-speed video, coupled with electron microscopy, to capture the light show. Her gear also included energy dispersive x-ray spectroscopy and computer modelling.
Her research opened another question about the disco clams - why the clams produce these light shows in the first place.
Dougherty's next experiments focused on observing the clam's 40 eyes to determine whether they could see their light shows themselves. She believed clams might perform the light shows to attract their mates or to confuse predators.
Further details of the study were published in June 26 issue of the Journal of the Royal Society Interface.
