Hobbies And Interests
Taxonomy
Rodents belong to the Rodentia order of mammals, currently divided into three suborders: Scuirognathi, which covers squirrel and mouse-like rodents; Hystricognathi, or guinea pig-like rodents, including coypus and porcupines; and the less familiar Anomaluromorpha, which includes springhaas and scaly-tailed squirrels. Despite appearances, rodents are more closely related to other placental mammals such as humans and cows, than to marsupials such as possums.
Distinguishing Characteristics
Rodent teeth are distinctive. All rodents have two pairs of incisors, strong molars and no canines. Their incisors are for gnawing and continue to grow throughout the animal's life. Herbivorous animals need a way to digest tough plant material, and rodents do this with a combination of gut bacteria and re-ingesting fecal pellets. This function is roughly equivalent to cows chewing cud--the food goes through the animal's digestive system twice.
Habitat
Rodents have colonized almost every terrestrial habitat on the planet and some aquatic ones. There are rodents that live mostly in trees, such as flying squirrels; in the tundra, such as lemmings; underground, such as naked mole rats; in rivers, swamps and lakes, such as beavers; and in human habitations, such as the ubiquitous house mouse and Norwegian rat.
Diet
Many rodents are omnivores, eating a variety of plant and animal material. Animals such as hamsters, squirrels and mice eat whatever they can find, including nuts, seeds, invertebrates and fruit, but are not active predators. Some rodents are grazing animals, such as the coypu of South America, which feeds on aquatic plants. A few rodents, in particularly grasshopper mice, are true carnivores, stalking and hunting prey with the same techniques as much larger mammalian predators. A grasshopper mouse displays similar behavior to a lion despite being a tiny fraction of the size.