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Known as “the disco clam,” this six-centimeter shellfish has tentacles that flash like a strobe light. At first, researchers thought the light was a type of bioluminescence like fireflies or deep-sea angler fish. But last year marine biologist Lindsey Dougherty from the University of California, Berkeley, found that the flashing lights are caused by highly reflective silica spheres in the clam’s bright orange lips. They initially thought the glow attracted mates, but now, new research from her team suggests that the light display may ward off would-be attackers.
St. Fleur provides some great footage of the clam defending itself from the formidable mantis shrimp. The above video shows off the disco clam’s light show.