How are certain animals determined as Rodents?

As in, why would a specific animal be called a rodent (physical characteristics, behaviors, etc)?How are certain animals determined as Rodents?
It's everything to do with anatomical distinctions and nothing whatsoever to do with behaviour. The skeleton, skull and teeth have to be put together in the necessary way, and so does the genetic make-up. It's a matter of ancestry. All rodents are descendants of a common rodent ancestor.





I've never read a diagnosis for Rodenta, as it happens, but that doesn't mean such a thing hasn't been written. I've read about some of the dental requirements. Among those are the need for having open-rooted, ever-growing teeth; chisel-shaped, self-sharpening incisors; and lots of other wacky and wonderful details.





Update


%26lt;%26lt;Rodents are characterised by two continuously-growing incisors in the upper and lower jaws which must be kept short by gnawing%26gt;%26gt;





The same applies for lagomorphs, meaning bunnies and relatives, which aren't actually rodents. Therefore, the charactor isn't definitive of rodents.How are certain animals determined as Rodents?
The defining feature of rodents is the four large incisor teeth at the front of the mouth. These grow constantly and must be worn down by eating hard foods or by gnawing - the term rodent comes from the Latin 'rodere', meaning 'to gnaw'.
usually their teeth, as they need to always eat to stop them from growing to long
Rodents are characterised by two continuously-growing incisors in the upper and lower jaws which must be kept short by gnawing





Forty-percent of mammal species are rodents, and they are found in vast numbers on all continents other than Antarctica.





Common rodents include mice, rats, squirrels, chipmunks, gophers, porcupines, beavers, hamsters, gerbils, and guinea pigs.





Rodents have sharp incisors that they use to gnaw wood, break into food, and bite predators. Most eat seeds or plants, though some have more varied diets. Some species have historically been pests, eating human seed stores and spreading disease.
it all with the skull and teeth. nothing with behavor. also some thing to do with the heartbeat.