The ears of wild canids come in only one shape: natural. But among domestic dogs, selective breeding has produced a number of different ear types, each with its own names, courtesy of dog breeders, fanciers and kennel clubs.
Among the most common varieties are the erect or "pricked" ears sported by many of the more wolf-like breeds, such as German shepherd and basenjis, and by semi-domestic canids, such as dingoes and New Guinea singing dogs.
Most hound dogs feature hanging or "pendant" ears, while many terriers have semi-erect "button" ears in which the tips fold over and hang in a V-shape, partially covering the opening.
Button ears can been seen in Sheltland Sheepdogs and many terriers. Ears are third-quarters tipped over facing forward. In some breeds such as Shelties the button ear is not always natural and must be trained from puppyhood for the "proper" tipped look.
The "rose" ears found in some bulldogs and pugs, a variation of a drop ear, is folded inward along the back edge, with the tip curving over and back to show the opening to the ear.