A donkey is not a mix of any specific animals, but rather a domestic member of the horse family that is related to horses and zebras. However, donkeys can interbreed with other members of the family Equidae, and are commonly interbred with horses to produce mules and hinnies. A mule is the offspring of a male donkey (called a jack) and a female horse (called a mare), while a hinny is the offspring of a male horse and a female donkey (called a jenny) . Mules and hinnies are both a cross between a horse and a donkey, with unique characteristics that make them special. Mules are larger and taller than donkeys, and inherit desirable qualities from both donkeys and horses. However, mules are sterile, while donkeys can reproduce normally.