Scientists put 3-D glasses on praying mantises. As if that weren’t buggy enough, they then showed the insects a “3-D movie.” By doing this, scientists discovered that the insects see in 3-D. In fact, they are the only known insects that can.

Scientists in the United Kingdom made “movie theaters” for mantises. After gluing the 3-D glasses on the insects, the scientists put them in front of the film. A movie of moving and still dots played. When the moving dots seemed to come less than an inch away, the mantises tried to catch them.

By learning how praying mantises see, we can make lightweight robots that can see in 3-D, says neuroscientist Vivek Nityananda. He led the team.