What is the mammalian order that includes rabbits, hares, and pikas?

The mammalian order that includes rabbits, hares, and pikas is Lagomorpha.

Lagomorpha contains two living families: Leporidae, which includes rabbits and hares, and Ochotonidae, the pika family. These animals are placental mammals and are found across much of the world, from grasslands and forests to rocky mountain habitats.

Lagomorphs are often mistaken for rodents because of their incisors and plant-based diets. However, rabbits, hares, and pikas have four upper incisors—two visible front teeth backed by a smaller pair—whereas rodents have two upper incisors. Lagomorphs also practice cecotrophy: they re-ingest nutrient-rich soft droppings to extract more energy from fibrous food.

The name comes from Ancient Greek words meaning “hare” and “form.” German naturalist Johann Friedrich von Brandt coined “Lagomorpha” in 1855, and the group was formally treated as a mammalian order in 1912. Rabbits generally raise altricial young in burrows, while hares give birth to more developed leverets above ground; pikas gather vegetation into winter haypiles.