The hallmark of this breed is the ridge on the back which is formed by the hair growing in the opposite direction to the rest of the coat. The ridge must be regarded as the characteristic feature of the breed. The ridge should be clearly defined, tapering and symmetrical. It should start immediately behind the shoulders and continue to a point between the prominence of the hips and should contain two identical crowns (whorls) directly opposite each other.
Except from Illustrations of the Breed Standard Breed Standard, Rhodesian Ridgeback Club of America
Where does that ridge on their back come from?
The Rhodesian Ridgeback's ancestry includes a dog native to Southern Africa -- a tribal dog, a companion and a hunter, with a ridge of hair growing backwards down its back. European settlers brought with them their hunting dogs, they, in turn, intermingled with the native ridged dogs. The ridge factor is fairly dominant and many a big game hunter discovered these "ridged dogs" had exceptional hunting ability and temperament. The hunters began to select specifically for the ridge and thus, the breed was born.
Where did the ridge originate?
No one knows for sure, but a plausible theory is that tribes living along the west coast had a lively trade with Asian sea-faring people. Prior to the arrival of the Europeans, these East African tribes had cattle, goats and sheep of Asian stock and it's conceivable that their dogs and the trader's dogs interbred. Some believe that the RR and the Thai Ridgeback are both related through an ancestor from the island of Phu Quoc, as both breeds share two genetic traits -- ridges and the dermoid sinus.
What about Ridgeless?
Beware of any breeder that may tell you that the puppy "doesn't have a ridge yet, but it will come in later". Ridgebacks are born with ridges or without ridges, they do not develop. A certain number of Ridgebacks are born without ridges, some people say that this percentage is around 10% but in our experience this is a high estimate. Ridgeless Ridgebacks do have a special place in our heart. Breeders typically note that these dogs are often the most beautiful in the litter. They have all of the wonderful characteristics of the breed, minus one cosmetic trait.