9 December, 2016

Are All Dogs Color Blind? Myths and Facts

Are all dogs color blind?

Are all dogs color blind? Is everything in a dog’s world black and white?  For many years we assumed that dogs could see only in shades of black, gray and white. Dogs do see color, but not in the same way as people do.  That idea been widely accepted for decades, but new understanding of canine anatomy have shown that, while they can’t see the same colors humans do, dogs are not color blind. Technicolor may be beyond their comprehension, but research shows that the dog’s eye can see much more than shades of gray.

Are All Dogs Color Blind?- Myths

The notion that dogs see only in black and white has been attributed to Will Judy, writer, and founder of National Dog Week. He claimed to be the first to declare that dogs had poor vision, able to see single shades and tones and only general outlines and shapes.”It’s is likely that all the external world appears to them as varying highlights of black and gray,” Rudy wrote in his 1937 manual, Training the Dog. In the 1960s, other researchers hypothesized that the only mammals that can discern color are primates. There was little research to back up this assertion, especially in dogs; nevertheless, it soon became common knowledge that our canine pals are color blind.  Are Dogs Color Blind or Spectrum Challenged?

Are All Dogs Color Blind?- Facts

In the last few decades, examinations of the canine eye structure have revealed some differences in basic design between humans and dogs. The differences were driven by function and evolutions.

Dogs developed their senses as nocturnal hunters, tracking and catching critters at night. Their eyes are adapted to see well in the dark and to catch movement. For the purpose of hunting in the dark, canine eyes have a larger lens and corneal surface and a reflective membrane, known as a tapetum, that enhances night vision.

Dog eyes are structured like and function similar to our own. The retina acts like a movie screen where light is focused and translated into the colors and shapes that the brain then translates into images. Both people and dogs share the same types of specialized light-sensory equipment, called rods and cones.

The rods respond to shades of black and white. Dogs have many more rods than people do in the central part of their eyes. Rods are most sensitive to changes in light which is useful for motion detection. That likely would have helped dogs tracking varmints – or Frisbees.

It is the cones – cells primarily responsible for visual acuity or sharpness – that determine how well we see and also detect color. People (and primates) normally have three kinds of cones, and these photoreceptor cells respond best to red, green and blue. This three-color system – called trichromatic vision – allows humans to detect different hues and their combinations, including yellows, oranges and purples and a variety of shades in between.

Are All Dogs Color Blind?- What Colors Can Dog See

Scientists now believe that a dog’s color vision is similar to that of a person who has red–green colorblindness. Dogs can make out yellow and blue, and combinations. This renders a lot of the world grayish-brown. That lush green lawn? It probably looks like a field of dead hay. That royal red velvet cushion? Still comfy, but it probably comes across as a dark brown blob to the dog.

dog looking into owners eyes

Are All Dogs Color Blind?- Best Colors For Dogs

Knowing that dogs don’t see certain colors, it would make sense to choose products that may be less aesthetically pleasing to you, but will be an eyeful for your dog. This knowledge may help explain why some dogs go crazy over yellow tennis balls, but are apathetic about the same ball in pink or red. One amusing or odd fact is that the most popular colors for dog toys today are red or safety orange (the bright orange red on traffic cones or safety vests).

However red is difficult for dogs to see. It may appear as a very dark brownish gray or perhaps even a black. This means that that bright red dog toy that is so visible to you may often be difficult for your dog to see. That means that when your own pet version of Lassie runs right past the toy that you tossed she may not be stubborn or stupid. It may be your fault for choosing a toy with a color that is hard to discriminate from the green grass of your lawn.” We hope this information puts all your questions to rest.