Rodent

Rodents are mammals of the order Rodentia which are characterized by a single pair of continuously growing incisors in each of the upper and lower jaws. Rabbits, hares, and pikas were once included with them, but are now considered to be in a separate order, the Lagomorpha. Most rodents are small animals with robust bodies, short limbs, and long tails.

About Rodent in brief

Summary Rodent Rodents are mammals of the order Rodentia which are characterized by a single pair of continuously growing incisors in each of the upper and lower jaws. Rabbits, hares, and pikas were once included with them, but are now considered to be in a separate order, the Lagomorpha. Most rodents are small animals with robust bodies, short limbs, and long tails. Most eat seeds or other plant material, but some have more varied diets. Mating among rodents can vary from monogamy, to polygyny, to promiscuity. Many have litters of underdeveloped, altricial young, while others are precocial at birth. Rodent molars are well equipped to grind food into small particles. The jaw musculature is strong. The lower jaw is thrust forward while gnawing and is pulled backwards during chewing. The rodent fossil record dates back to the Paleocene on the supercontinent of Laurasia. Rodents greatly diversified in the Eocene, as they spread across continents, sometimes even crossing oceans. Some species, in particular, the brown rat, the black rat, and the house mouse, are serious pests, eating and spoiling food stored by humans and spreading diseases. Accidentally introduced species of rodents are often considered to are invasive and have caused the extinction of numerous species, such as island birds, previously isolated from land-based predators. The specific morphological feature used for storing food and storing food is evident in particular subgroups of rodents like kangaroo rats, chipmunks, hamsters and gophers which have two bags that range from the front to the front of the mouth.

The Sciuromorphal order includes the rodent squirrels, the eastern grey squirrel, the rat-like squirrels and the gopher-like gerbils. The species of gophers may have two internal pterygoid muscles that may allow them to move the jaw further sideways when chewing when they have a cheek pouch. The brown rat has large large deep deep temporalis muscles making them able to chew powerfully with their molars. The guinea pig has larger superficial masseter muscles and deep masseter muscle making them less efficient at biting with the incisor. The black rat has enlarged temporalis. muscles making it able to chewing powerfully with its molars, possibly making it less efficient with theincisors, but possibly making them more efficient with chewing with their pterygiad. The gophers have enlarged internal. masseter. muscles and larger superficial. masseters making them easier to chew with their jaws. The rat, squirrel, and gerbil have two shoulder bags that may be used to store food and may have the cheek pouch that is used to storing food. The chinchillas and guinea pigs have a high-fiber diet; their m teeth have no roots and grow continuously like their incisory. In many species, the m teeth are relatively large, intricately structured, and highly cusped or ridged.