Dogs are wonderful, quirky and unique creatures. They come in all shapes, sizes and colors.
Each breed has an identifying marker. Dalmatians have their spots, Rottweilers have their ginger eyebrows and Chow Chows have unusually colored tongues.
So, what is the reason why Chow Chows Have Blue-Black Tongues?
It is a question experts and scientists have longed tried to answer, but as yet, there is no scientific reason or advantage to having a blue-black tongue. It is caused by an increase in pigmentation.
For us humans, extra pigmentation shows as birthmarks and freckles. In the Chow Chow and other breeds, this shows as spots on the tongue or a completely blue-black tongue.
How does having a dark colored tongue become an advantage? Perhaps it comes from the country they originated.
The Chow Chows is an Eastern breed, believed to be descended from the Simocyon in Northern Mongolia and China.
This animal was shared similarities with modern foxes and small bears. One of the main distinguishing characteristics was that it had 44 teeth.
Chow Chows also have 44 teeth, although they lose this extra pair in adulthood. All other dog breeds are born with 42 teeth.
Other small bears from the same region have the same blue-black tongue as the Chow Chow.
It could be that the frigid temperatures of their homeland meant having a dark tongue reduced heat loss from panting. It is a known fact that white reflects heat and darker colors absorb heat.
Pink At Birth
Chow Chow puppies are not born with their colorful tongues. At birth, their tongues are pink, like most other dog breeds.
At around 8-10 weeks of age, the blue-black pigmentation starts to develop. The Chinese Shar pei is the only other breed to commonly develop the same coloring.
However, even these two breeds do not exclusively have blue-black tongues. Some only develop a covering of colored spots and retain the pink coloration over the rest of their tongue.
It is a common misconception that the Chow Chow and Shar pei are the only breeds to have any blue-black coloring.
Large breeds like the Bull Mastiff, Newfoundland and Great Pyrenees also have a tendency to develop some kind of tongue pigmentation.
For these breeds, the coloring is not as strong or they may only develop spots of blue-black color.
This display of extra pigmentation may also show in other large breeds such as Retrievers, Setters, Rottweilers, Akitas and German Shepherds.
It is less common, but not unheard of for some small breeds like the Pomeranian to also display blue-black tongue coloration.
Interestingly, as Chow Chows reach their senior years, their blue-black tongues begin to lose the pigmentation, slowly turning their tongues back to the pinkish color they were at birth.
Purebred or Mixed Breed
Due to the Chow Chow being such an old and well-established breed, their uniquely colored tongue helps us identify purebred Chow Chows from those crossed with other breeds.
A Purebred Chow Chow will always develop the blue-black tongue between 8 and 10 weeks of age. A Chow mix may develop spots of blue-black or no spots at all.
This method of identifying purebreds and crossbreeds is one unique to the Chow Chow. No other dog breed can have their pedigree determined by a factor as simple as tongue coloration.
Blue-Black In Nature
This bizarre tongue coloration is actually more common in wildlife than people realised.
So many different animal species have this unusual coloring. Some are well known and the reasoning has been proven. For others, the blue-black tongue is still a mystery.
Large mammals such as Giraffe, Okapi (same family as giraffe) and Polar Bear all have blue-black tongues. Some are paler tones, while others have almost black tongues.
For the Polar Bear, it is widely believed that the darker tongue color helps reduce heat loss from the body due to living in such cold temperatures. For Giraffes and Okapis, the reason is unknown.
It is possible that they simply have a higher number of pigmented cells that other animal species.
Livestock also frequently show darker tongues. Although most farm animals tend to have pink tongues, it is quite common for a small number of cows, sheep and goats to be born with purple or blue-black tongues.
Birds, particularly parrots, also often have dark colored tongues. Birds like the Macaw and similar parrot species have large blue-black tongues. again, the reason is unknown and there may not be an advantageous reason for it.
Speculation for this unusual adaptation has been ongoing since the Chow Chow was first brought to Europe in the 1500s.
There have been many theories shared to try and unearth this particular mystery, however, it may be one that we will never truly know.
Since evidence suggests this breed was around before the Han Dynasty of 202 BC, we may never uncover the truth to this fascinating genetic quirk.
Brearley, J.M & Draper, S. (1992) The World of the Chow Chow, TFH Publications
Draper, S. (2004) Chow Chow- A Kennel Club Book, Kennel Club Books
Rushing, A. (2015) Chow Chows Revealed: All you ever wanted to know about the reclusive Chow Chow, Independent Publishing Platform
Triggs, J. (2015) Chow Chow Training Guide, Independent Publishing Platform
Wilcox, C. (1999) The Chow Chow, Chapstone Press: Minnesota
Various Authors. (2010) The Chow Chow – A complete anthology of the dog – Vintage Dog Books