Hamsters Are Rodents
| Hamsters belong to the Rodential orders of mammals. So, what exactly is a rodent?
Rodents are by far the largest mammalian order. Rodents are characterized by front teeth adapted for gnawing and cheek teeth adapted for chewing. Rodents have enlarged, chisel-shaped upper and lower front incisors that grow throughout their lives. These have hard enamel on the front surface and soft dentine on the back surface, so that unequal wear keeps the chisel edge sharp. There is a gap between the front teeth and the cheek teeth. When the lower jaw is in a forward position, for gnawing, the upper and lower incisors are in contact but the upper and lower cheek teeth are not; thus, wear on the cheek teeth is avoided. The cheeks are drawn in behind the incisors when the animal is gnawing, so that bits of hard material cannot be swallowed. When the lower jaw is pulled back into the chewing position, only the cheek teeth make contact. The approximately 1800 rodent species are divided on the basis of their anatomy into 3 suborders. The Sciuromorpha, or squirrellike rodents, include the various species of squirrels, chipmunk, marmot, ground hog, prairie dog, gopher, pocket mouse, kangeroo rat and beaver. The Hystriomorpha, or porpupinelike rodents, include the porcupine, cavy, guinea pig, chinchilla, as well as many species whose name include the term rat (e.g., the South American bush rat). Hamsters belong to the third suborder Momorpha, or mouselike rodents. Other animals in this category include the great variety of mouse and rat species, as well as lemming, vole, muskrat, gerbil, dormouse and jerboa. The rabbits and hares were once classified as rodents because of their large, chisel-shaped incisors. However, they are quite distinct anatomically and have a long, separate evolutionary history; they are now classified in an order of their own, the Lagomorpha.
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