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A new study finds an amazing device used by fish as a camouflage from ocean predators.

The research is innovative and can help military technologists to create effective techniques for camouflage in the oceans, the University of Texas at Austin reported.

Studies show that fish use microscopic structures called platelets in their skin cells that help to reflect polarized light, which disguises them from hungry predators. This light's waves travel on the same plane. Under the water, the light is mostly "polarized", with fish able to identify variations of the light.

"Fish have evolved the means to detect polarized light," said Molly Cummings, professor of integrative biology in the College of Natural Sciences. "Given that, we suggested they've probably evolved the means to hide in polarized light. If we can identify that process, then we can improve upon our own camouflage technology for that environment."

The fish is a good guide to help the U.S. Navy learn how to camouflage in open water.

Hence, researchers built a video polarimeter in order to document polarized light in real time, looking at polarized light in the same way as fish do. With an automated rotating platform to hold the fish in place, they measured it with the polarimeter.

Scientists documented more than 1,500 different angular configurations. According to the study, a couple of fish, the lookdown and the bigeye scad, exhibited better camouflage in polarized light than a mirror.

These fishes could camouflage themselves better than reef fish and surface-skimming fish that are not able to usually see polarized light. The fish could camouflage themselves best at "chase angles," that jut out 45 degrees in all directions from the tail or head. These are the angles at which a predator would be pursuing the fish.

The main reason for the camouflage was the structure of platelets inside the skin cells, working to scatter polarized light in different directions depending on the angles. These findings would one day be used in real-world applications, researchers hope.

"I think it's a great example of how human applications can take advantage of evolutionary solutions and the value of evolutionary biology," Cummings said. "It's important for people to recognize that we take advantage of evolutionary processes and solutions all the time and that even our military does."

The findings were published in a recent edition of the journal Science.