A staple of farms for centuries, sheep are domesticated for their meat, skin, fur, and genetics. As herbivores and ruminants, sheep follow a feeding pattern of grazing and chewing cud. With hundreds of species of sheep, these mammals are quite diverse in hair types and sizes. Ranging from one hundred to four hundred pounds, sheep generally grow to be as old as a decade or two. With excellent senses of hearing and smell, sheep make up for their lack of depth perception. As a flock, sheep are easily swayed by food but also must abide by the pecking order.