Although the Shetland is one of the smallest breeds of horse, measuring no more than 46 inches (117 cm) high, it is extremely hardy and needs little care, having adapted to the harsh climate and scarcity of food in Scotland’s Shetland Islands. Shetland ponies were thus used as pack horses and worked in England’s coal mines in the 19th century. These diminutive horses are also known for their gentle disposition and are a favorite mount for children. Shetland ponies can live to be how old? Discuss