When fluffy goes crazy for laser pointers, shiny objects and people’s ankles, what is she seeing?
Cats’ penchant for jumping on their feet and feather toys may be rooted in their hunting instincts, but it also has a lot to do with their unique vision. And it turns out that scientists know a lot about what cats see.
Now a new set of images, by artist Nickolay Lamm, attempts to capture the differences between a cat’s vision and human vision. while humans can see more vibrant colors during the day, their feline companions have the upper hand when it comes to peripheral vision and night vision. [images: look what a cat sees]
nocturnal creatures
Cats have a wider field of vision: about 200 degrees, compared to 180 degrees for humans. cats also have a greater range of peripheral vision, all the better for spotting that mouse (or toy) squirming around the corner.
Cats are crepuscular, which means they are active at dawn and dusk. that may be why they need such good night vision. their eyes have six to eight times as many rods, which are more sensitive to low light than humans.
In addition, the elliptical shape of cats’ eyes and the larger corneas and tapetum, a layer of tissue that can reflect light back to the retina, also help it collect more light. The tapetum can also change the wavelengths of light that cats see, making prey or other objects silhouetted against a night sky more prominent, Kerry Ketring, a veterinarian at the Eye Clinic for Animals in New York, wrote in an email. whitehall, mich. [10 surprising facts about cats]
Their extra rods also allow cats to sense movement in the dark much better than their human companions.
color vision
but cats don’t have an advantage in all areas. the human retina has about 10 times as many cones, the light receptors that work best in bright light, as do cat eyes.
“Humans detect movement in bright light 10 to 12 times better than cats or dogs, since vision in bright light is a conical function,” Ketring said.
Humans also have three types of cones, allowing them to see a wide spectrum of colors, with peak sensitivity in red, green, and blue. while cats can have three types of cones, the number and distribution of each type varies. in behavioral tests, cats do not seem to see the full range of colors that most humans see.
Some experts believe cats’ color vision is limited to blues and grays, while others believe it is similar to that of dogs, but with less richness of hue and saturation of colors, ketring said. dogs see the world in fewer tones than humans and cannot distinguish between red, yellow, green and orange objects. fish, by contrast, can see ultraviolet wavelengths that humans cannot see.
myopic
Humans can also see with much higher resolution, with a wider range of vibrant colors, thanks to the many cones in their eyes.
Humans can see objects clearly from 100 to 200 feet (30 to 60 meters) away, but cats don’t need to be more than 20 feet (6 m) away to see those same things clearly.
Because cats lack the muscles needed to change the shape of their eye lenses, they can’t see things as clearly as humans and need to be farther away, ketring said.
and while fluffy may be better at spotting the rapids and scurries of a frightened mouse, there are plenty of slow-moving objects that humans can spot with their eyes that cats find immobile.
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