Pack Mules

A mule is the offspring of a male donkey and a female horse. The mule is valued because, while it has the size and ground-covering ability of its dam, it is stronger than a horse of similar size and inherits the endurance and disposition of the donkey sire, tending to require less feed than a horse of similar size. Mules also tend to be more independent than most domesticated equines other than its parental species, the donkey.