Tiny sharks use their glowing bellies to hide from predators, according to new research.
Smalleye pygmy sharks, which live off the coast in the Indian and Pacific oceans, is only about eight inches long.
According to Live Science, the small shark contains hormonally-controlled organs called photophores to use as camouflage.
The pygmy sharks use the phenomenon while hunting jellyfish on the water's surface.
Read more on GlobalPost: Florida man Steven Egan mistakes girlfriend for hog, shoots her
According to Science, while hunting, the sharks make their bottoms glow to create narrow silhouettes of light that make it hard to spot against a background of downwelling light.
Research lead Julien Claes of the Universite catholique de Louvain in Belgium, along with colleagues, looked at nearly 30 sharks, testing their skin against various chemicals.
The study revealed that hormones regulated the use of bioluminescence, which is altered by changing the degree of pigmentation covering the photophores, said Live Science.
Essentially, the sharks used hormones to open and close pore-like organs to reveal glowing skin.
The scientists detailed their findings in the Journal of Experimental Biology.