rodentie

Rodentia, sometimes referred to as rodents (rodentie in some languages), is the largest order of mammals, comprising more than 40 percent of all mammal species. The defining feature is a pair of continuously growing incisors in the upper and lower jaws, used for gnawing. These incisors are usually orange-brown from iron in the enamel and are separated from the cheek teeth by a gap called a diastema. Most rodents lack canines or have only very small ones.

Rodents occupy nearly every terrestrial habitat and some aquatic environments. Their size range spans from tiny mice and voles to large beavers and capybaras. Diets are diverse, including seeds, vegetation, insects, and occasional animal matter. This ecological versatility helps rodents thrive in deserts, forests, grasslands, and urban areas.

Taxonomically, Rodentia is divided into several subgroups, such as Sciuromorpha, Myomorpha, and Hystricomorpha, with major families including Muridae (mice and rats), Sciuridae (squirrels), Castoridae (beavers), and Caviidae (guinea pigs and relatives). The order likely originated in the Paleocene to early Eocene, with the earliest rodent fossils dating around 60 million years ago and diversifying extensively in the Cenozoic.

In ecosystems, rodents perform important roles as seed dispersers, prey for many predators, and, in some cases, ecosystem engineers. Humans rely on rodents as model organisms in biomedical research, while others pose challenges as agricultural pests or urban nuisances. Conservation status varies widely among species, from abundant to endangered due to habitat loss, climate change, and introduced competitors or predators.