Researchers have created the world's smallest 3-D glasses for praying mantises to wear while watching 3-D movies.

The experiment isn't just for the insects' entertainment: Scientists hope to learn more about 3-D vision and possibly apply their findings to future robots, PBS reported.

As the only invertebrate known to have 3-D vision, the praying mantis is key to understanding how seeing in three dimensions works as researchers compare the insect's sight to a human's.

 "Despite their minute brains, mantises are sophisticated visual hunters which can capture prey with terrifying efficiency. We can learn a lot by studying how they perceive the world," lead researcher Jenny Read of the Institute of Neuroscience at Newcastle University said in a school news release.

For the first stage of the project, the researchers put 3-D glasses on the insects, attaching the tiny devices with beeswax. The mantises then sat in front of computer-generated images on computer screens.

The research to explore the mechanisms of mantis 3-D vision is the first of its kind since Samuel Rossel discovered the insect sees in three dimensions in 1983. The data could be used to build robots in the future.

"This is a really exciting project to be working on. So much is still waiting to be discovered in this system," Vivek Nityananda of the Newcastle University Institute of Neuroscience said in the news release.

"If we find that the way mantises process 3D vision is very different to the way humans do it, then that could open up all kinds of possibilities to create much simpler algorithms for programming 3D vision into robots."

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