Scientists have made tiny 3D glasses for praying mantises to learn if they can see three dimensions. United Kingdom researchers wanted to use the special glasses and bug movies to learn if insects like animals with backbones such as toads, owls, cats, and monkeys have 3D vision.
The researchers are from the UK's Newcastle University. Their findings were published in the journal Scientific Results, which is a Nature open-access journal.
In the past scientists used a less complex method using prisms of different powers to test the stereopsis (3D vision) of a praying mantis. It showed that the bugs see like humans do but did not verify that they can see in three dimensions, according to CBS News.
The first glasses the scientists used were 3D glasses like the ones handed out at movie theaters. However, they did not work because the bugs were too near the screen.
Scientists then made little "anaglyph" eyewear. They are like old-school 3D glasses with a red and blue lenses that are free prizes in cereal boxes.
The tiny bug could not see red light well. Scientists then changed to blue and green lenses, which emulated vision with 3D depth.
The insects were put in a freezer for a couple of minutes so they would be motionless. Then the researchers stuck them onto modeling clay, and used a blend of pine resin and beeswax to stick the glasses onto the mantises, according to The Verge.
Scientists used computer-generated images to add the shape of praying mantis' prey on a bright background. While wearing the 3D glasses the bugs tried to attack the images, but they did not do that while seeing two-dimensional images.
Jenny Read is a professor of vision science at Newcastle University. She explained that even though the bugs have tiny brains they are skilled hunters that can capture prey using high efficiency.
The scientists wrote that they had provided clear proof that insects have 3D vision, and their methods can be used for other research. That can provide a better understanding of human depth perception and how eyes see 3D images. It could also help to develop algorithms for 3D depth perception in supercomputers.