Researchers from Newcastle University built a 3D cinema for insects, along with an old-school pair of 3D glasses, in order to determine if the praying mantis perceives objects in 3D. Stereopsis has been shown in mammals, amphibians and birds but little was known about how insects perceive 3D.

The glasses were constructed out of one blue and one green lens, because praying mantises see red light poorly, attached to the mantis with beeswax. The mantis was then shown footage of bugs crawling around. 2 dimensional footage of the bugs were ignored but when the bugs were shown in 3D the mantis would strike out at them, confirming that mantises do use 3D vision similar to vertebrates. Initially, researchers tried using polarized lenses similar to modern 3D technology but found that the screen was too close to the subject for the images to be properly separated.

It is hoped that understanding stereopsis in simpler systems such as insects will lead to the development of robust stereo algorithms for use in robotic 3D sensors.

Further information: http://www.nature.com/articles/srep18718