Praying mantises are badass hunters. Although famed for their ability to catch prey many times heavier than themselves, there’s not much research on the efficiency of mantis vision, or indeed on insect sight in general.
To help see the world through the eyes of an insect, scientists have been giving praying mantises 3D glasses to see if they are capable of stereopsis – the ability to perceive depth and view the world in three dimensions – and if this is what makes mantises such effective predators. Along with this, the findings from these funky bugs hope to help develop depth-perception “sight” in robots.
The study conducted at Newcastle University had its findings published in Nature this week.
Using beeswax to attach the glasses, they fitted the praying mantises with two separate 7-milimeter blue and green lenses. They didn’t use the more iconic red and blue lenses we’re probably more used to, as red light is poorly visible to mantises.
The insects were then placed into their very own 3D insect cinema. Upon the screen they played swirling images designed to provoke them into thinking there was prey up for grabs.
Acting as if they were amid a real hunt, when wearing the 3D glasses the mantises believed the stimulus was prey and begun to strike at the LED screen. When they weren’t wearing the lenses and were confronted with the 2D stimulus, they didn’t bother to attack the screen. These findings neatly show that some insects can see in 3D and praying mantises heavily rely on three-dimensional vision to survive.
"Despite their minute brains, mantises are sophisticated visual hunters which can capture prey with terrifying efficiency," said study leader Jenny Read in a press release. "We can learn a lot by studying how they perceive the world."
"Better understanding of their simpler processing systems helps us understand how 3D vision evolved, and could lead to possible new algorithms for 3D depth perception in computers".