By Dr. Becker
As if our feline companions weren’t mysterious enough, a new report out of the City University London reveals that the common housecat sees things that are invisible to the human eye.
Where you see the soft colors of a spring flower, your kitty sees psychedelic stripes. You might admire the subtle colors of a bird’s feathering, while little Fluffy notices the jazzy patterns on those same feathers. Kitties are also able to see the urine marks of other animals dotting the landscape near and far.
Origins of Your Kitty’s Super-Vision
The phenomenon behind feline super-vision is the ability to detect ultraviolet (UV) light. The City University London study, published recently in the Proceedings of the Royal Society B,1 indicates that cats, dogs and certain other animals can see UV light, which is typically invisible to humans.
In an interview with Discovery News, study co-author Ronald Douglas points out that:
"There are many examples of things that reflect UV, which UV sensitive animals could see that humans can't. Examples are patterns on flowers that indicate where nectar is, urine trails that lead to prey, and reindeer could see polar bears as snow reflects UV, but white fur does not."
The researchers concluded that not only cats, but also bats, dogs, ferrets, rodents, and the okapi (also known as the forest giraffe or zebra giraffe), all have the ability to detect substantial levels of UV light.
UV Sensitivity Could Explain Why Your Cat Obsesses Over Strange Objects
Scientists have long known that many invertebrates see UV, along with birds, fish and some reptiles and amphibians. But it has been generally assumed that most mammals possess vision similar to a human’s, and lack the visual pigment required to see UV light.
It appears that the transparent parts of the eyes in certain animals transmit UV wavelengths. This allows more light to reach the retina (which is beneficial to cats who like to prowl at night).
According to the researchers, this ability might also explain why kitties often become fixated on weird objects. Optical brighteners are sometimes added to paper, fabrics, and other consumer products to make them appear brighter. Since optical brighteners absorb UV light, they might appear particularly intriguing to UV-sensitive housecats.
UV-Sensitive Animals Don’t Seem Bothered by Exposure to UV Rays
Even though UV light is considered harmful to the eyesight of humans, it appears UV-sensitive animals aren’t bothered even by repeated exposure. It could be that cats, reindeer and other animals with the ability to detect ultraviolet light are somehow protected from visual damage.
Since UV light is thought to create fuzzy images, it could explain why the human eye has a lens that removes the UV. Without that lens, the world would appear as a big blur. So perhaps our kitty companions have traded the ability to see details for their psychedelic super-vision. Not a bad exchange, all things considered!