Q Why do chipmunks, squirrels, rabbits and beavers have the same kind of teeth?

— Cora Wieneke, Mount Horeb, Wis.

A Erin Flynn, conservation education curator at Henry Vilas Zoo in Madison, Wis.:

Squirrels, beavers, chipmunks and rabbits all have similarly shaped teeth because all of those animals have teeth that continually grow throughout their lives.

Just like your fingernails grow continually throughout your life — you have to clip and file them to keep them healthy and strong — these animals must chew a lot to keep their teeth nice and sharp.

They need to take care of and maintain their teeth so they don’t grow too much. The teeth must be able to fit in their mouth so that they can keep eating.

Beavers, chipmunks and squirrels are all in the rodent family. Rodents tend to be omnivores, which means they can eat a little bit of everything. Rabbits, on the other hand, are vegetarian (herbivores).

Some rodents are more specialized, like beavers. They have those huge teeth that are really great for chewing down the trees they use to make dams, their homes.

A great rule of thumb with animals is that form follows function. If you look at the body and teeth of an animal, you can generally figure out what kind of habitat they live in and what they eat.

Sharp canine teeth, like you would see on a cat or dog, is usually a sign of a predator. Generalized teeth can be a sign of an omnivore. With something like a beaver that has such strong teeth prominently in the front, it’s always a good bet that it is a chewer.

Blue Sky Science is a collaboration of the Wisconsin State Journal and the Morgridge Institute for Research.