Yes, bugs have 3D vision! Miniature glasses have proven that mantises use 3-D vision, providing a new model to improve visual perception in robots. 3D vision in mantises was originally shown in the 1980s but this work used prisms and occluders which meant that only a very limited set of images could be shown. The new research team has developed 3D glasses suitable for insects which means they can show the insects any images they want, opening up new avenues of research.
Most knowledge about 3D vision has come from vertebrates, however, a team from Newcastle University, UK publishing in Scientific Reports, confirm that the praying mantis, an invertebrate, does indeed use stereopsis or 3D perception for hunting.
In a specially-designed insect cinema, they have shown that it needs to be ‘old school’ 3D glasses for tests to work on mantises. While in humans that would be with red and blue lenses, red light is poorly visible to mantises so they have custom-made glasses with one blue and one green lens!
In the experiments, mantises fitted with tiny glasses attached with beeswax were shown short videos of simulated bugs moving around a computer screen. The mantises didn’t try to catch the bugs when they were in 2D. But when the bugs were shown in 3D, apparently floating in front of the screen, the mantises struck out at them. This shows that mantises do indeed use 3D vision.