Prairie dog and Clark in 1804. Lewis described it in more detail in 1806, calling it the "barking squirrel". On average, these stout-bodied rodents will grow to be between long, including the short tail, and weigh between . Sexual dimorphism in body mass in the prairie dog varies 105 to 136% between the sexes. Among the species, black-tailed prairie dogs tend to be the least sexually dimorphic, and white-tailed prairie dogs tend to be the most sexually dimorphic. Sexual dimorphism peaks during weaning, when the females lose weight and the males start eating more, and is at its lowest when the females
Prairie dog are pregnant, which is also when the males are tired from breeding. Prairie dogs are chiefly herbivorous, though they eat some insects. They feed primarily on grasses and small seeds. In the fall, they eat broadleaf forbs. In the winter, lactating and pregnant females supplement their diets with snow for extra water. They also will eat roots, seeds, fruit, and buds. Grasses of various species are eaten. Black-tailed prairie dogs in South Dakota eat western bluegrass, blue grama, buffalo grass, six weeks fescue, and tumblegrass, while Gunnison’s prairie dogs eat rabbit brush, tumbleweeds, dandelions, saltbush, and cacti in addition to