Allie Pence’s pets come running when she calls, their whiskers quivering and brown eyes blinking. She strokes their fur and runs her finger down their tails. Their eyes are beadier than those of most household pets, their tails long and ropy. Each weighs, at most, little more than a pound. They do not bark or meow; they squeak.

They are rats.

And they wander Pence’s Bloomington apartment for about an hour a day, sitting on her shoulders or just running around on the couch, before retreating into their cages.

As pets go, rats don’t have the greatest rap. They’re associated with garbage, sewers, all that is filthy. And yet two years ago, Pence found herself buying Ella and the now-departed Margo for $5 each. “I had wanted a pet for a while, and I knew I didn’t want a dog or cat because they live a long time, and I didn’t want to move with pets after I graduated,” says Pence, a senior at IU studying community health.

Rats, with a lifespan of about two years, seemed like a good substitute. “My friend had rats as pets, and I knew they were affectionate,” says Pence, who later adopted three more—Froot Loop, Trix, and Coco Puff—via a rat-adoption website. (The Bloomington Animal Shelter often has pet rats available for adoption.) Domesticated rats, also called fancy rats, come in many breeds, which vary by fur color, length, and ear size; dumbo rats, for example, have big, floppy ears.

Regardless of variety, pet rats are clean, Pence says. “And I’ve read that they’re smarter than dogs. They’re like puppies that can run on my shoulder.”

Rodentologists agree: Rats are seriously clever. “Rats that survive to the age of four are the wisest and the most cynical beasts on earth,” an exterminator once told New York magazine. “A trap means nothing to them, no matter how skillfully set. They just kick it around until it snaps; then they eat the bait.… I believe some of them can read.”

As for Pence’s pets?

“My friends don’t particularly like them,” she says, “but they accept that these are my pets and they don’t knock them in front of me. And that’s all I really ask.”

Video by Mark Johnson