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By Dr Ivan R. Schwab

Well, yes, sort of. Dogs see colors, but their span of color vision closely resembles the array of colors seen by “color blind” males.

About 8%, or 1 out of 12 males (humans) and about 1 out of 200 females are “color blind.” We use that term to describe individuals that are color deficient, but they are not truly color blind. The eye has cells that perceive color and these are called cone photoreceptors or “cones.” We use another set of photoreceptors called “rods” for the black and white vision of dim light or nighttime. Our cones contain three visual pigments each of which responds to a different spectrum of wavelengths of light. It is these three visual pigments that combine their signals to permit us to have color vision by blending the signals, depending on the wavelengths received. Although it is an over-simplification, and misleading to some extent, we can describe our visual pigments as blue, green, and red. The brain receives the input from these three channels and then interprets the color we see. At least two different color channels are needed for color vision because the brain needs to “compare” these two different channels to determine color.

Color blindness in humans is caused by the genetic deficiency or loss of either the green or the red photopigment hence that input into the brain. So, the brain learns to see only those colors that can be interpreted or constructed by combining the input from the other two remaining visual pigments. The result is a less robust spectrum of colors, but colors are still seen. True color blindness in humans does exist when two of the three visual pigments are genetically unavailable, but it is exceedingly rare. If only one visual pigment channel is coming to the brain, say the blue cone input, it isn’t seen as blue but rather as on or off—hence that is “real” color blindness and would be a black and white world.

So, almost all color blindness in humans is not true color blindness but would be better described as color deficiency.

Now, let’s go back to your dog. Normal dogs have two different visual pigments in their cones, and much like humans afflicted with so-called “color blindness.” But they would see color. The color input would be weaker to some extent because dogs have fewer cones than we do because they are evolutionarily closer to their nocturnal ancestors. Cones are needed less, if at all, at night.

So, what about the other pets in the household? Your cat will have a similar color distribution as your dog although there are some subtle differences.

Birds, on the other hand, possess rich color vision, in many cases better than our own. Most birds have four cone visual pigments, although this varies. In general, birds have an additional ultraviolet pigment in their cones and many more cones than we have. Furthermore the visual pigments that would be similar to ours span different wavelengths. Their visual experience is richer than our own in ways impossible to describe or understand. Not o

My etching class ended last night. I was able to pull one more print that I’m almost happy with, but will now be renting space at the Atlanta Printmaker’s Studio in order to study the craft and practice more. In the meantime, here is last night’s progress on the hummingbird piece. The drawing looks a little labored due to my having to redraw through the hard ground and having to reapply and redraw the soft ground details as well, and in this printing, I left a fair amount of ink on the plate for more plate tone….

My instructor, Kathy Garrou, brought in a book done completely in engraving! How crazy that? It’s a GORGEOUS book called TRICK OF THE TALE, written by John and Caitlin Matthews and illustrated by Tomislav Tomic. This book is published by Candlewick Press, who is ironically the publisher of my next book, WHITE WATER~ I can’t wait to add this book to my collection.

From the publisher: Enter (carefully) the world of the tricksters, those wily creatures who lie their way out of trouble, cheat when they get a chance, and devise elaborate tricks to get what they want — with delightfully unpredictable results. This truly diverse, elegantly illustrated collection follows such clever characters as Anansi, Coyote, Brer Rabbit, and others who play a role in a multicultural array of storytelling traditions, from African to Inuit to European, Tibetan to Native American to Japanese. Celebrate the slyest trickster tales from around the world in a lavish volume that gives a well-loved story tradition its rightful due.

Speaking of WHITE WATER…back to work~

To offer you a quick look at the greeting card designs that were delivered just yesterday (woohoo!), I’m posting a few pages from my catalog, so you can see the kind of stuff I’ve been up to! I’m currently working on a new design for this site, complete with an online store, so soon you will be able to see all the designs in living color! Click the images below to see them larger. Note: the colors won’t be quite as neon in print. Enjoy!

Color visuals line - 1

Cartoons - 1

Sprout line - 1

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Thompson, Kate. 2007. The New Policeman.

Originally published in Great Britain in 2005, The New Policeman has already won some prestigious awards--the Whitbreat Children's Book Award and the Guardian Children's Fiction Prize. (It is always nice to read these kidlit imports in my opinion. They're often quite different and provide a nice change of pace.) J.J. Liddy may seem like your average Irish boy, but his life is about to become quite the stuff of fairy tales. When his mom asks for 'more time in the day,' J.J. never one to disappoint tries his best to "buy" this present. After all, he would like more time in the day as well. His whole neighborhood, his whole village, seems obsessed with this lack of time and the constant feeling that their lives are being drained away too quickly. With the help of a neighbor, Anne Korff, J.J. is off on the adventure of a lifetime. It is a dangerous quest where he'll meet new friends and make new enemies. This quest for "more time" may end up costing him his life. Full of adventure, music, and magic, The New Policeman is too good to miss.