Mules

Characteristics

Mules inherit from donkeys the traits of intelligence, sure-footedness, toughness, endurance, disposition, and natural cautiousness; from horses, they inherit speed, conformation, and agility. They grow faster and live longer, giving them a larger interval of productivity compared to horses or donkeys. They rarely become ill, unlike horses, who often need to be checked for worms, and like their donkey fathers, mules can see their hind legs and have hooves better suited to dry climates. Additionally, the skin of mules is tougher than that of horses or donkeys, and they tend to live longer on fewer resources than do horses. Mules are reputed to exhibit a higher cognitive intelligence than both of their parent species, but robust scientific evidence to back up these claims is lacking. Preliminary data exists from at least two evidence-based studies, but it relies on a limited set of specialized cognitive tests and a small number of subjects.