How Do Dogs See?

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By disecting the eyeball of a dog, researchers found that about 10% of the photoprecepters are cones. Cones are responsible for helping the brain detect colors. The photoreceptors in our eyes are 100% cones. This means that we can process all the colors and see them more vividly. A dog can’t tell the difference between red, yellow, orange, or green but they can see whites light blues, purples and different shades of grey.

 

Besides just the cones, there are other photoreceptors known as rods. Rods can only detect black and white, but they also process movement extremely well and help to see in the dark. A dogs photoreceptors are mostly rods. This means they can see exceptionally well in low light conditions and see different shades of grey to a higher degree than we can. They can also differinciate the tiniest movements you make. If you’ve ever stood still with your dog in the back yard at night in a shaded area, and caught him by suprise, your dog has probably barked at you. This is because while you are standing still, he doesn’t know who you are. Once you move, even wiggle your finger, he knows its you. This is helpful to an animal that hunts in the dark! On top of having an eye full of rods, they also have a reflective layer that helps to reflect light, helping them to see even better in the dark. This reflective layer is the glow that we see when we shine a light on a dogs eyes in the dark. As a matter of fact, it is believed that a dog can see in 4 times lower light levels than we can because of this reflective layer.

 

Another thing that comes into factor when talking about a dogs vision abilities is that they can see 240 to 250 degrees around them without moving their eyes. Our field of vision is only 180 degrees. So even if you are standing diagonally behind your dog, chances are he sees you.

 

Even though dogs are able to see all of these different things with their eyes, vision is not their primary sense. Actually, dogs are considered nearsighted. They really don’t trust their eyes as much as we trust ours. Instead, they trust their sense of smell. To them, the phrase "follow your nose" is a way of life. I’ll write more about that in another blog entery.

 

So what about T.V.? Do dogs enjoy watching T.V.? Well, T.V. is a series of flickering pictures that are streamed together to make a moving picture. The pictures are broadcast at a rate of about 60Hz, which is how fast they need to move for us to see them as a moving, flawless picture. To a dog, watching T.V. is a lot like watching and old scratchy silent film because their flicker fusion seems to occur at a rate of 70 to 80Hz. So they see the pictures flicker slower and there for it seems choppy to them. So chances are that if your dog likes to watch T.V., it’s probably because of the sounds. Hearing is a dog’s secondary sense, and I will discuss that in another blog entery.

 

So there you go. You now know the basics of how a dog sees his world. Keep in mind that this is usefull information to have in the training field. Because dogs are so adapt to detecting movement, they often respond to hand signals better than to voice commands. It’s a good idea to teach your dog both. I hope you feel closer to you canine friend now that you understand a bit better how he or she precieves the world.

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About thecanineguru

I am a canine behaviorist of 23 years and offer canine rehabilitation, training, and behavior change to clients under the given name "The Canine Guru." I am known mostly for my online presence through my blogs, Doggy Times and Doggy Times II. Both were honored by MSN Editors multiple times. My methodology focuses on energy and how to use and read it. I firmly believe in operant conditioning and positive reinforcement. I don't feel that choke, pinch, or electric collars are necessary when working with dogs. The harshest method I ever use is the squirt bottle and the occasional touch, or poke. I'm known for "speaking" to dogs in their own language using body language, energy, touch, and the occasional sound.
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29 Responses to How Do Dogs See?

  1. Ron says:

    Thanks for that. I am not an expert in these things but the last but one paragraph concerning dogs watching TV I question. My own dog, in general, ignores the TV. Even the sounds are ignored although there are times when she hears an animal sound on the TV that she will look up. But there are times when there are no obvious animal sounds but animals are featured that she will definitely respond i.e. raise her head and look at animals on TV, be they dogs, lions, horses etc. and even somtimes walk over to the TV and look more closely at the screen. She clearly watches with interest but then switches off when the animal is no longer present on the TV. This seems to belie the statement that… "So chances are that if your dog likes to watch TV, then it’s probably because of the sounds."

  2. Weiz says:

    My dog did the same thing,I also tried to mute the sound but he was still staring at the animals in TV.

  3. Brandon Ross says:

    You guys make a valid point. I did not include the fact that all dogs are different when it comes to watching t.v. Herding and hunting breeds are also likely to watch t.v. because of the movement. As I stated, dogs pick up on movement very well. Also, some videos made for dogs have a faster refresh rate of 70 to 80Hz so that dogs will be able to see a smoother picture. Also, some of the newer flat screen and HD televisions have a faster refresh rate which would make it easier for your dogs to watch. Thank you for catching that! However, there is still debate over wether or not dogs can see in 2D. So your dog may not know it’s an animal on the t.v. and may just be responding to the noise or movement.

  4. Joan says:

    I have 2 Pugs 5 & 6 yrs old, whenever they see a animal on tv they go crazy. I just adopted these guys a few weeks ago. They are characters for sure.

  5. John O says:

    Re: dogs seeing 2D images. I have a golden retreiver and a chocolate lab. The golden definately picks up on animals on t.v. ESP dogs. With sound or not. My choco could either care less or just doesn’t pick up on the images. So there is absolutely no doubt in my experience that dogs see 2D.

  6. Wini Camp says:

    My dog goes nuts for animals on TV especially dogs, cats, and horses. However if I show him a picture of these animals in a magazine, for example, he shows no interest. I guess movement is a big deal, LOL. I was wondering about that- thanks for the info!!

  7. tasha says:

    i think its more to do with how the dogs brain works when concerning sight. they can obviously see in 2d but movement means more to them than a still image. one way to test this would be to get a cardboard cut-out of a shifty looking dark figure and place it strategically in the house somewhere. will be fun to see if the dog reacts to it. my dog also loves to watch tv, wildlife documentaries are her fave as she has a rather confused look on her face when elephants are on the screen lol

  8. Pingback: La visión en los perros | Gran Planeta

  9. Pingback: ¿Cómo ven los perros? « Dsousa10

  10. Bob says:

    Human’s don’t have 100% cones.

    ‘The retina contains two types of photoreceptors, rods and cones. The rods are more numerous, some 120 million, and are more sensitive than the cones. However, they are not sensitive to color. The 6 to 7 million cones provide the eye’s color sensitivity and they are much more concentrated in the central yellow spot known as the macula. In the center of that region is the ” fovea centralis “, a 0.3 mm diameter rod-free area with very thin, densely packed cones.’ — http://hyperphysics.phy-astr.gsu.edu/hbase/vision/rodcone.html

  11. buzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz says:

    i have 4 greyhounds i can now see why the go crazy over any little moving animal.

  12. John Marshall says:

    Actually, as a point of correction, we also have rods in our eyes. In fact, humans have about 120 millions rods and about 6 or 7 million cones. Those cones in the human eye are concentrated in the fovea (a very small area) and the density accounts for our strong sensitivity to color. Dogs have around 360 million rods (3x ours), which combined with the reflective layer allow them to see very well in the dark. I don’t know if the dog has fewer cones than we do (although as you mention, they only have 2 kinds and we have 3 kinds).

    The cones in a dog’s eye are more spread out than our eyes with helps account for their weaker color resolution.

    Dogs also have a much larger cornea than we do (which also helps gather light) and an invisible eyelid (the nictitating membrane) which acts like a windshield wiper. You can’t normally see the nictitating membrane on your dog unless its inflamed due to an injury or illness. The idea is that they can clean and moisten the eyeball without blocking out their vision like our blinks do. Pretty cool.

  13. lolster says:

    thank you i just o all my answers for science

  14. Deborah says:

    Thanks so much I have always wondered about my Bud watching tv, keeping him company; while I am away now it seems dumb to keep the tube on. Now I will play some nice jazz.

  15. John says:

    I have a Rottweiler who watches the football. When there is a close up of the ball at the footballers feet he will reach a paw or put his head to it. This has been a regular occurence when he was younger but not as much in his later years.

    • Deborah says:

      I think my Bud replies to more sounds, I don’t sit next to the TV and he is glued to my side as Bichons do, but
      he will sometimes look up when dogs bark on tv otherwise I don’t think as our wise guide said see tv.

  16. maisie says:

    thank you i needed this for my homework

  17. navjavie knowles says:

    thank u for the information it was helpful and very interesting

  18. Katie says:

    Very cool. Thanks for the post!

  19. Ethan says:

    Soo my dog can see me when I am behind her

  20. I cannot believe that a dog only see in 2D. Two eyes would always result in a 3D image, would it not. Please correct me if I am wrong. Even your 2D Iphone can make a 3D image by moving the camera over 4 inches.

  21. There’s been lots of debate over this article since I published it. Please keep in mind that dogs are an on going field of study and over time findings change. The majority of this info was taken from a text book, and is here for reference only. This article is not intended to be a definite end of discussion matter of fact statement. Keep in mind that ALL dogs are different, and some may in fact watch TV regularly. If this is the case with your dog, consider contacting your local canine research facility so it can be studied further.

  22. connie says:

    i have a 6 week old hound/minigrayhound mixed puppy –female- i dont think see can see how can i tell –she follows me –or is that my shadow

    • You can look to see if her eyes are clouded, or watch to see if she’s bumping in to things. A flashlight works to determine if the dog’s pupils dilate, but the best way is to take her to the vet.

  23. Right here is the perfect web site for anybody who would
    like to find out about this topic. You understand so much its
    almost hard to argue with you (not that I personally would want
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  24. Indira Neufville says:

    My dog doesn’t watch t.v at all even if there are animals he will just raise his ears.

  25. Jas says:

    Thanks. Really good stuff to know!

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