While there are organisms, like the Pacific lamprey and the star-nosed mole, that move through the world without the benefit of sight, most have evolved to communicate and interpret information through light and color. Some creatures have evolved extravagant displays, complex camouflage techniques, coordinated attack behaviors, and more, all thanks to color vision. As it turns out, many animals also have their own unique visual languages based on their specific visual adaptations.
We know that what we call “visible light” is just a narrow slice of the electromagnetic spectrum. The sights and colors we humans see are defined by our visual system, particularly the photoreceptive cells in our eyes known as rods and cones. Other animals, however, have different collections of rods and cones. Some have more (like the mantis shrimp), while others have fewer (like dogs). As a result, other species quite literally see the world differently from us. And it’s not just a matter of colors; some animals can see beyond human perception, like the UV vision found in reindeer, jumping spiders, and other animals.
Many of us, at one time or another, have wondered if the colors we see are the same as the colors other people see. It might be an impossible question to answer. It’s probably not possible to see with perfect certainty through the eyes of another person, but a report published in the journal PLOS Biology shows that scientists have made progress in recreating the visual experience of other species with entirely different visual systems.
Looking at animal vision with fresh eyes
Scientists have been able to recreate animal vision to a certain extent for a while now, but with some serious limitations. Through a process known as multispectral photography, researchers capture light in a broad spectrum, gathering data beyond the human visual range. Scientists can then filter those images to recreate an approximation of what a non-human animal sees. It works pretty well but typically requires still images and very specific lighting conditions.
However, a multidisciplinary team primarily hailing from the departments of Biology, Computer Science, and Statistics at George Mason University has come up with a new approach to recreating what animals see. The system, developed along with colleagues from the School of Life Sciences at the University of Sussex, the School of Environmental Sciences at the University of Guelph, and the U.S. Naval Research Laboratory, works on moving images. It does so by taking into account characteristics like motion in the visual field, illumination, reflectance, and photoreceptor sensitivity — all without bespoke hardware.
How scientists recreated animal vision with off-the-shelf tech
While the results are cutting-edge, the hardware involved is relatively mundane. The system was built using off-the-shelf parts, including Sony a6400 cameras and an 80 mm f/5.6 EL-Nikkor enlarger lens held in a 3D-printed housing. Additional hardware includes a beam splitter, which separates UV light from visible light and sends the two signals to independent cameras. In addition to UV, the system also captured visual information in blue, green, and red channels simultaneously.
Passing through the lens, light encounters a dichroic beam splitter, which reflects short-wavelength light less than 425 nm. That light then passes through a filter that only transmits wavelengths less than 390 nm. Finally, that light travels to a camera modified to capture UV light. Meanwhile, visible light with wavelengths between about 425 and 720 nm passes through the splitter and is captured by a second camera. That visual data is then bumped up against the known visual sensitivities of various animals to recreate results akin to what they might actually experience.
The ability to depict the world as it is perceived by a different species could help us understand layers of experience previously underappreciated, like the way different lighting conditions impact vision across different species. In addition to scientific research, it could have applications for entertainment in things like movies and nature documentaries, allowing filmmakers to more accurately depict an animal’s point of view.
Stephan is the sports journalist for the Maple Grove Report.
