We think of indoors and outdoors as separate, divided by the walls of our home. Inside, we control things: temperature, light, cleanliness, orderliness. Outside, nature calls the shots. Sometimes the line gets blurred.

In our house, various of our children occasionally traverse through. But mostly it is Pam, me, and the cat now. Except when the line between in and out is blurred, and we have uninvited guests.

Early this winter, I was in town. Pam called to report breathlessly that she had extricated a bat from the kitchen. A broom and a dish towel were skillfully used in the roundup.

Years ago, our home regularly had winged visitors, more often birds. A wire guard around the chimney put an end to that. So, the bat was a surprise. So was the next one.

That evening, Pam was in bed watching Netflix, when I heard a shriek. I ran upstairs to find the covers over her head. Then I saw the second bat darting about, looking at least as frantic as my wife. Pam yelled something about a tennis racket. I raced downstairs to look for that. I haven’t played tennis in 20 years, so had no idea where it was.

I grabbed the broom and a box. I spent some time swinging and missing. (It reminded me of my baseball career.) Finally, I knocked our visitor to the floor, got him/her into the box, and outside. I like bats, so was happy to see it fly off into the night when I opened the box.

When I see bats in the farmyard on summer nights, they are more a shadow than a real thing. I got a good look at our bat-guest as it was flying directly at me. About 6 inches with its wings extended, it was cute in a bat sort of way. As I said, I like bats. Anyone who eats mosquitoes is a friend of mine. We still aren’t sure how they got into our house. We assume they were a pair. There haven’t been any bat sightings since.

Our bats were a surprise. Mice aren’t. We usually have a caravan of mice looking for a winter home each autumn. Sometimes a couple, sometimes up to a dozen end up in a trap. It’s possible an exceptionally smart one or two isn’t falling for the old trap trick and overwinters with us.

One memorable morning, I was getting breakfast for our kids before school. One of Abby’s cat-friends was in the house at the time. In a hallway just off the kitchen, the cat suddenly leapt upon an unfortunate mouse making its way home from a night of crumb-hunting. I’m not sure if you have ever heard a cat eat a mouse, but there is loud crunching. The kids were repulsed and intrigued and excited. Nothing in science class that day could have been half as interesting.

About 20 years back we had the Plague of the Ladybeetles, a plague of biblical proportions. The Eurasian ladybeetle was brought to North America to protect crops. Turned out they absolutely loved soybean aphids and multiplied by the gabillions. It was fine to have them chomping aphids out in our fields, but then they began to seek shelter for winter.

Farm houses were perfect for that. They got in by the thousands, crawling on every window and across the ceiling. They had a clever defense mechanism of being stinky if you did anything to them. Kamikaze bugs dive-bombed into my coffee. It was as if they were trying to drive us from our house.

There were raging debates about the difference between the ladybeetles and ladybugs. Everyone was an entomologist. It seemed a distinction without a difference. For whatever reason, the plague passed before we were forced to move to the Arctic.

These structures we call homes are meant to shelter us from nature. Inside, we are isolated from the world outside. It is an enclave in that way. That’s a good thing when it is -20 outside. We are blessed to have one if we do, as millions on our planet do not have permanent and safe shelter.

Nature has ways of intruding, as our bats, mice, and bugs give evidence to. There are other critters, too: flies, spiders, fruit flies, and a few creepy, crawly things that show up in the basement. It is said that the most adaptable species on Earth are human beings and rats. Rats flourish wherever people migrate to. I’m pretty sure Pam would be gone if there were rats in the house.

Of course, we are trying to maintain these abodes on top of what used to be the tall grass prairie. Human beings are disruptive of nature wherever we take up residence. But nature has a way of adapting and likes to fill a vacuum. Which is a good thing. Otherwise mankind probably would have killed off this planet long ago.

Long before we came along, Brown County was home to a vast array of prairie plants and creatures that evolved over millennia. Maybe our forebears should have tried harder to live within the natural systems that were here. Or at least maintained more of what was here in preserves, like a museum to honor the natural past. But they didn’t, and our homes are mostly surrounded by lawn and pavement and millions of acres of corn and soybeans. Prairie was pushed to the margins, tiny margins.

I was talking to a farmer during a late spring once when we were having trouble getting into the fields. He was disappointed that plants were growing out in his untilled fields. He thought after all the years he had controlled weeds that the seed bank should have been reduced to none.

I remember thinking it was a good sign that nature was prepared to cover that soil with growing things if we couldn’t. Unfortunately, it is not the ancient prairie plants that were sprouting. It was the common weeds that farmers do battle with. I suspect though, that given time, the prairie would have returned. We see that where programs to reestablish prairie are in place. It is a testament to the nature’s resilience.

Man vs. nature is the ancient battle. Now we know that is a wrongheaded way to see this. If it is a battle, both sides lose. We begin to understand man must work with nature if we are to survive.

In this worldview, bats and other critters have their place. Maybe not in our house, though.