Are Dogs Color Blind? - The Answer is Not so Black and White

 

At one time or another we have all probably heard someone state that dogs cannot see in color. The actual facts behind this theory do not lead to a simple or “black and white” answer. It is a much argued topic that has been extensively researched in the past and when it comes down to it the answer to the question “Are dogs color blind?” is a little more complicated.

Actually, dogs can and do see in color. However, it is not the same way that you or I use our vision. The eyes of the canine species are considered to be dichromatic, which basically means that the can see two colors. Dogs can pick up colors within the blue and yellow spectrum. To compare, the human eye is classified as trichromatic and can see blue, yellow, and red.

So technically, by missing out on the red side of things dogs could be considered color blind and, in reality, they do not see the world like an old black and white TV show or movie. To understand this concept it is important to take a look at the anatomy that contributes to it. The typical “eye” consists of rods and cones. Rods are responsible for seeing color and cones enable the eye to perceive black and white.

We humans have eyes that contain approximately 7 times more cone material than our canine counterparts. The number of cone cells contributes directly to the way we see color. Because dogs have a lower cone count in their eyes they see colors as much more washed out and faded than we do.  To make up for this shortcoming, dogs do have more rod cells in their eyes then humans. This enables them to see better in low light conditions, which was essential in their wild and undomesticated days.    

So what do dogs actually see then? And how does their view of the world differ from ours? Dogs see certain colors and shades of gray. Since they are primarily tuned into the blue and yellow spectrums of light they can be considered to be blind to the red-green spectrum. This is comparable to a human who is color blind. Dogs will see green and red differently which is more of a yellow-brown or gray. The figure above shows how the colors we see on an everyday basis would correspond to what a dog sees.

The question arises then that if a red chew toy is lying out in a field of fresh green grass, will it appear invisible to your dog? Not at all. To compensate for the color blindness dogs have developed a highly tuned sense of depth perception.  This is a result of their eye position in regard to their head. They also have better movement tracking vision, which is optimal at long range. Nature has provided your dog with a unique set of traits that allow them to get along just fine and are finely tuned to a dog’s needs.

When dogs begin their lives as puppies, they are born with closed eyelids. It generally takes a couple of weeks of development before they start to open up and gaze upon the world with milky blue eyes. By around 8 weeks the eyes have matured and changed to a more permanent color and puppies will begin to see their first hints of color, although their vision is still coming into focus for a few weeks after that.

In contrast, as dogs age, their eyes sometimes begin to cloud over. This is mainly due to “nuclear degeneration” which occurs as the lens of the dog’s eye gets denser with age and begins to change the way the eye works. This may sound pretty scary but, in reality, the dog’s vision is normally not affected too much.

So, are dogs color blind? Yes they sure are. Do they just see the world in just shades of gray? No, that is just a myth. Dogs and humans definitely see things differently, both literally and figuratively. Your furry friend has the perfect vision setup for their needs and daily routines and being color blind by our standards is in no way a real disadvantage for them.

---

Russ Barker enjoys writing blog articles that everyone can understand which answer some of the big mysterious questions concerning pets, for example "Are Dogs Color Blind?". He finds the answers and passes the knowledge on so that everyone can be better informed. Russ is the chief blogger for DogTagArt.com, a company that strives to keep all pets safe with their one-of-a-kind pet ID tags. These handmade custom dog tags feature over 500 artist designs and give you the ability to design your own using photos or artwork. It's a creative way to promote pet safety and gets people excited about their ID tags.

Why Do Dogs Eat Grass?

From time to time, we all have probably noticed that our canine companions can graze out in the yard like so many of their bovine brethren. For some it may even be a day to day occurrence. Although any sudden change in your dog’s behavior or eating habits should be noted and relayed to your veterinarian, usually this hankering for grass is not something to necessarily get real worried about. But the question remains – Why do dogs eat grass?

Evolutionary Explanation

When it comes down to it, domesticated dogs are not natural hunting carnivores. They are not really classified as full omnivores though as they will eat just about anything in order to satiate their hunger and receive the nutrients their bodies need. If we move down the evolutionary ladder we begin to see that the wild ancestors of modern canines gobbled up every single part of the meals they had skillfully scavanged. This regularly included the stomach contents of smaller animals who ate only plants. So even though their diet concentrated on meat and protein intake they also got a little green mixed in.

If we move forward to today’s time and the eating habits of the modern dog we can see how they might occasionally seek out grass or other vegetable matter as a substitute. They still need to obtain those vital nutrients that plants can provide and they have to find it elsewhere. But why do dogs eat grass specifically, especially when the end result is usually a sick or vomiting pup?

Continue reading "Why Do Dogs Eat Grass?"

---

Russ Barker is a real person dispite his perfect name for the pet idustry. He, like so many others, has often wondered why do dogs eat grass. So he spent time researching this habit and wrote an awesome blog article for you. Russ is the head blogger for DogTagArt.com, a business dedicated to supplying the world's pets with awesome one-of-a-kind pet ID tags. These safe and stylish custom dog tags are a fun way for them to encourage pet safety and responsibility and ensure that lost pets make it back to their homes and the ones they love if lost.