Animals that Glow in the Dark - Bioluminescence is Not New Technology

Scientists have recently cloned pigs and cats that glow in the dark. But did you know that there are many animals that glow in the dark naturally? The ability for a creature to glow in the dark is known as bioluminescence. Bioluminescence is defined as "the production and emission of light by a living organism as the result of a chemical reaction during which chemical energy is converted to light energy." Here are a few animals that are capable of glowing in the dark.

Firefly

Probably the most commonly known animal that glows in the dark is the firefly. Fireflies, or lightning bugs, are small insects of the beetle family and are capable of being bioluminescent. The firefly uses bioluminescence primarily at night to attract a mate. There are over 2,000 species of fireflies and their bioluminescence ranges from a pale red to yellow and green in color.

Angler Fish

The angler fish resides in the ocean in waters that are too deep for sunlight to penetrate. This unique fish is known for appendages that grow out of its head. The appendages are used as lures to attract prey. The angler fish's appendages are bioluminescent and when they glow, small fish are attracted to the light. When a fish is within reach, the angler fish strikes and gobbles up the smaller fish.

Flashlight Fish

Flashlight fish are small fishes with light organs near their eyes. These light organs act as flashlights for the fish. This fish uses bioluminescence to help it find food in the dark.

Cookie-cutter Shark

The cookie-cutter shark swims in waters up to 3,300 feet deep. Sunlight is still able to penetrate the water at the depth that this shark swims. Its belly is bioluminescent, helping to camouflage it from fish swimming below it. The entire belly of the cookie-cutter shark glows a pale blue-green to match the water above. Only a small, unlit dark patch on the belly is not bioluminescent. Predatory fish such as tuna and mackerel are tricked by the dark spot and mistake it for a small fish worth eating. While the tuna or mackerel thinks it is going to get a meal, the larger cookie-cutter shark attacks and makes a meal out of it instead. The cookie-cutter shark is the only fish known to attract prey by the absence of light.

Shining Tube-shoulder Fish

The shining tube-shoulder fish does exactly what it sounds like. This fish has tubes on its shoulders which are used to spew bioluminescence out into the face of an attacker. The cloud of bioluminescence temporarily blinds the predatory fish in dark waters so the shining tube-shoulder fish can hurriedly make an escape.

Squid and Shrimp

Some species of squid and shrimp have bioluminescence capabilities. The squid and shrimp capable of bioluminescence typically reside in water where sunlight and moonlight easily penetrate the surface. Their bellies glow a green-blue to match the color of the water above them, offsetting the shadow that would normally be cast by the sunlight shining down from above. If it weren't for bioluminescence, their shadow would attract predators.