United States Forest Service MULE un-edited

Mules are the hybrid product of a male donkey and a female horse. Male mules are called johns and female mules are called mollies. Mollies generally have a gentler disposition than johns. Intelligence, agility and stamina are all characteristics of mules. These qualities combine with a quirk of nature to make mules excellent pack animals. Unlike horses, which carry about 65 percent of their weight on their front legs, mules carry 55 percent on their front legs. This makes them very well balanced and surefooted, just what you want on backcountry
Mules form close bonds with horses, especially mares. The bond is so close that mules willingly follow a mare. That is why you may often find a mare, wearing a bell, leading a string of mules. A wrangler, or mule skinner, can usually control an entire pack string simply by controlling the bell mare. At night in the backcountry mule skinners can picket the bell mare and turn the mules loose. The mules will disperse and graze freely yet remain close to the mare. Environmental impacts are reduced and the mules are easy to gather in the morning.
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