Do Dogs See the World in Black and White?

I wasn’t exaggerating when I said that Speedy goes gaga over shopping for Penny. A few days ago, he came home with two new collars for her — blue and orange — and declared that he’ll buy her more in every color. I’ve lost count of how many collars Penny has in addition to the body harnesses. And the dog leashes are, of course, in brightly attractive colors too. The pup’s female, after all, and in our culture, we have that perception that girls like colorful accessories.

It didn’t take long before Speedy wanted to remove the collar that Penny was wearing to replace it with one of the two he had just bought. On a whim, he held both collars over Penny’s head, the pup leapt up and grabbed the blue collar in her mouth.

“So, you like blue…” Speedy said.

I was watching them and the scene was just too cute not to be photographed. I took my camera, asked Speedy to hold the two collars up again. Penny leapt up once more but, this time, she grabbed the orange collar. It was night time, the lighting wasn’t perfect, the first few photos I took were blurry so I asked Speedy to do it again. The third time that Penny leapt up, she grabbed the blue collar again.

“Ano ba talaga gusto mo — blue o orange (Which do you really prefer — blue or orange)?” Speedy asked.

After downloading the photos on my iMac, I suddenly remembered someone telling me long ago that dogs have a grayscale vision — meaning, they see the world in black, white and shades of gray. Who told me that and when, I can’t recall anymore. But the recollection of the statement made me wonder if Penny perceived any difference at all between the two collars or if she merely grabbed was what nearer or the collar held by the hand that moved more. That got me Googling.

No, dogs don’t see the world in black and white. But neither Penny did not see the blue and orange collars the way we do.

Humans see the world in color because we (usually) have three types of color receptor cells, or cones, in our eyes. These are sensitive individually to red, green, and blue light, and the different intensities and proportions of those three colors as seen by our eyes are put together by the brain to create the full-color world as we know it.

Some humans, however, are colorblind… Two of the more common types are red-green and blue-yellow, in which a person cannot distinguish the two colors named…

For dogs, their color vision is most similar to a human with red-green color blindness, although there are other differences. Dogs are less sensitive to variations in gray shades than humans are, as well as only about half as sensitive to changes in brightness. [Source]

Using the RGB spectrum at Dog-vision.com, it appears that Penny saw the orange collar as a dull yellow-gray and the blue collar as a shade of lavender. It just might be possible that Penny chose the blue collar two out of the three times that the Speedy held the collars over her head because the color appeared more attractive to her. I mean, from my point of view, I wouldn’t choose dull yellow-gray over lavender at all. But then, I’m not a dog so that’s just a guess.

It’s an intriguing thought though if colors affect dog behavior. And considering that Speedy has already decided that Penny will be wearing a costume next Halloween, if color does affect dog behavior, we better choose a costume in a color that won’t have Penny throwing a tantrum.