The deep-sea shrimp Parapandalus hurls a glowing cloud of organic matter to confuse a potential predator in a laboratory image.
The species is among a clutch of previously known bottom dwellers discovered to make their own light during an expedition off the Bahamas, according to a new study.
Scientists aboard the manned submersible Johnson-Sea-Link collected and observed a bevy of glowing creatures—including sea cucumbers, sea anemones, bamboo corals, and a new species of hermit crab—at depths approaching 3,280 feet (a thousand meters).
As one of the first groups to study bioluminescence among bottom dwellers, the team also examined many of the creatures they'd collected in the laboratory.
Their results suggest that bioluminescence could help deep-sea animals color-code their food, said study co-author Tamara Frank, a marine biologist at Florida's Nova Southeastern Oceanographic Center.
"It's possible that these animals are using the different colors of bioluminescence to decide, Yes I like that, no I'm not interested in that," Frank said.
Another revelation: Deep-sea animals tend to glow green, rather than the typical blues emitted by species living in the water column.
"Down on the seabed, there's a lot of current activity and detritus in the water that may make it difficult to see blue light," she said. "The green light would carry a little bit further."
(See "Pictures: 'Supergiant,' Shrimp-Like Beasts Found in Deep Sea.")