Today’s writing prompt was rats.

Rat snuggling in a human hand

Photo from nytimes.com

I like rats. I always have. I think it helps that I was raised in pristine suburbs where rats only appeared as tidy white-furred pets in cages — or as unhappy meals for my high school biology teacher’s pet python — and that I read Mrs Frisby and the Rats of NIMH when I was fairly young.

Rats always seem so intelligent. I love their bright round eyes, their energetic sniffing noses quivering with whiskers, their tiny-fingered paws. When I learned about their use in scientific testing I was upset. I know it often has to be done, but I felt sure these clever creatures would have some inkling of what was happening to them, enough to make elaborate plans for escape and set up a new community in a rosebush if only they’d been given the proper hints.

It’s weird that I like rats, because I also love cats, and that love is older. But then my cats, too, were clean suburban householders who would hardly stand a chance against a sufficiently calculating rat. I never saw the two as enemies; I never saw them together at all. And after all there are those videos on the internet of cats and rats being friends. The ones I knew could have been that way, their instincts quashed out by regular feeding and indoor life.

I like mice, too, but they never seem quite as smart as rats, even though more books have been written about them and I was devoted to the Redwall series for years. Mice are too small. It sounds very weird to say that small creatures make me think of bugs, but there’s something there — all those little squirming bodies. I like creatures to be bigger, to take up enough space that I couldn’t keep more than one or two at a time. Though come to think of it, I guess fear of rats is instinctive enough that the image of multiple rats in my house — even tame, loving, smart pet rats — grosses me out. The word “infestation” comes to mind.

My youngest sister is working with mice now. She recently turned 20 and when none of the school research jobs accepted her she sent out her own queries and received an acceptance from a university on the opposite coast, to work as an unpaid intern in a lab with a cardiology focus. You could say she is their summer lab rat.

Her experiment deals with cardiac tissue, which is to say heart cells. Thanks to her I’ve learned that heart tissue can be removed from the heart and the cells will still beat on their own. This makes me feel all kinds of creepy. For some reason I have always had a weird feeling about the heart and the fact that it beats nonstop for your entire life. I don’t know if this is because of that heart attack video we watched in third grade, or because in fourth grade I was out of school for a month with a rare disease with potential heart impacts. My sister was telling me about the heart cells beating under the microscope, and I got all crawly and told her why.

“But the heart doesn’t beat for your whole life,” she said. “The cells are always refreshing, so you have a new heart all the time.”

“I know,” I said. “But it still bothers me.” All those heart cells working so hard, in spite of mayonnaise and tonkatsu, in spite of my lack of exercise.

Anyway, the beating cells under her microscope belonged to a mouse’s heart, and more specifically, to the heart of a mouse that was only a day old.

“I don’t have to kill them myself,” she told me. But someone did, and because of the nature of experiments, they’ve had to kill quite a lot of them.

“So some poor mama mouse is being kept pregnant to make babies to be killed?” I asked.

“I guess so,” she said.