Science

New 3D vision discovered in praying mantis

New 3D vision discovered in praying mantis

Each of our eyes sees a slightly different view of the world.

Other animals have stereo vision too, including monkeys, cats, horses, owls and toads, but the only insect to have it is the praying mantis.

In a video released alongside the research, Jenny Read, study author and professor of vision science at Newcastle University, in the United Kingdom, first describes how human vision works: each human eye captures a slightly different picture of the world in front of us, creating a three-dimensional whole. A team of scientists is studying how the praying mantis perceives objects in three dimensions by making it wear tiny 3D glasses. The mantis lashed out at the prey, giving scientists hope that more lightweight robots with vision can be created by this method.

Who would've thought praying mantises had so much to teach us.

Also known as "stereopsis", 3-D or stereo vision helps humans and other creatures determine the distances to objects we see. According to the researchers, the 3D vision in praying mantis allows them to spot changes that occur in the movies, although human eyes can't identify those changes. The researchers showed the mantis images that wouldn't make any sense to a person: an object that moved up for one eye and down for the other.




Praying mantises don't need to be able to tell the difference between still images either, as they only hunt moving prey. These insects can perceive objects differently compared to humans. We do this by matching up the details of the picture seen in each eye.

Apart from looking quite cool, the praying mantis shared its novel means of utilizing its 3D vision. They did so even when humans couldn't.

But mantises focus on where the brightness is actively changing between the two images, allowing them to tell the distance to their target even when it is camouflaged against a similar background, the study found.

What's more, when researchers presented the mantis with 2D dot patterns, which are normally used to test human 3D vision, they found that the mantis was actually able to detect the movement while completely ignoring the still images.

"This is a completely new form of 3D vision as it is based on change over time instead of static images", Nityananda said. "In mantises, it is probably created to answer the question, 'Is there prey at the right distance for me to catch?'" The mantis is the only insect known to have stereo vision, but given its tiny brain, scientists have long suspected it must involve a simpler process. Researcher Jenny Read believes that this form of 3D vision can be used in robots with a lot less computing power than is now required.