Närilised

Närilised, or rodents, constitute the order Rodentia, a highly diverse group of mammals defined by a pair of continuously growing incisors in each jaw. These incisors are chisel-shaped, grow throughout life, and are kept sharp by constant gnawing. A gap, or diastema, often separates the incisors from the cheek teeth. This dental architecture supports a gnawing lifestyle and a wide range of feeding habits across species.

Rodents are the largest order of mammals, comprising thousands of species that inhabit nearly every terrestrial environment. They include familiar groups such as mice and rats (Muridae), squirrels and marmots (Sciuridae), beavers (Castoridae), and guinea pigs and capybaras (Caviidae), among others. Their size spans from small, mouse-sized species to large forms like the capybara. Rodents are found from deserts to forests, wetlands to urban areas, and many are adapted to nocturnal or crepuscular activity patterns.

Ecology and life history vary widely within the group. Diets range from strictly herbivorous to omnivorous, with some species specialized for seeds, bark, or aquatic vegetation. Reproduction is typically prolific, with many species producing multiple litters per year under favorable conditions. Lifespans also vary, with smaller species often living only a few years in the wild while some larger forms live longer in protected environments.

Humans have a multifaceted relationship with närilised. They can be agricultural pests and disease vectors, but they also play important ecological roles as seed dispersers and prey. Rodents are widely used as model organisms in scientific research. Conservation status ranges from common to endangered, influenced by habitat loss, climate change, and invasive species in various regions.