By Devon Murphy  

You might not like this — in fact, you almost certainly won’t — but your house is full of insects. Not just in your house either, but in everyone's! And it's not just a few … there's a lot. Insects like being inside just as much as we do, but we know almost nothing about the creatures that share our space.

centipedeThis centipede is just one of the hundred or so insect species living in your house.

That’s why a team of scientists from North Carolina State University, featured in the documentary The Great Wild Indoors, created the first ever indoor bug census called the “Arthropods of the Great Indoors.” They discovered a diversity of insects that they never expected.

“Our houses are really kind of novel ecosystems from an evolutionary perspective. And there’s still so much to learn and discover, even in these spaces where we spend the vast majority of our time,” said Michelle Trautwein, a research scientist at the California Academy of Sciences and a member of the census team.

A Community of Bugs Live In Our Homes

They found between 32 and 211 species of arthropods — an exoskeleton-covered creepy crawly — in every home they studied. Most were usual suspects were carpet beetles, and dust mites. There were also some other surprises along the way. For example, a kitchen sample the team brought back to the lab contained microscopic hermit crabs.

“We found a lot of rare interesting things that we had never seen outside in even a decade of collecting outdoors,” said Trautwein. “Houses seem almost as likely of a place to find rare, bizarre insects as the outdoors is.”

SCENE FROM THE FILM: We think our homes are ours alone, but they are actually shared by an entire community of insects.

Trautwein and her team started their study with 50 homes in Raleigh, North Carolina They sent two entomologists into a house at a time to scour every room. Each field mission took between two to seven hours. The team was decked out with headlamps, kneepads, forceps and vials just as they would on any other species-gathering mission. “When we would go out we would prepare ourselves for a full expedition,” said Trautwein. “It looked like we were ready to go into the rainforest.”

Bugs Have Been Unlikely Roomies Since Our Caveman Days

Their findings tell us a few things about our tiny little friends — namely, having insects in our houses isn’t really up to us. Even houses that underwent regular pesticide treatments still contained dozens of species. The team recently published a paper on some of their findings. They found that homes in wealthier neighbourhoods tend to host more arthropods. The paper posits that it’s a combination of house size and proximity to vegetation. Wealthier areas also tent to have more tree and parks. 

Since their initial search, the study has expanded globally. They are now collecting data from San Francisco, the Peruvian Amazon, Sweden and Japan, with trips set for Australia and an African site within the next year. Many of the species the study mentions over and over again are found globally, and that’s something that particularly interests Trautwein.

"If you really look at bugs and take time to get to know them a little bit, they’re just spectacular creatures."

“Humans, as we migrated out of Africa and eventually spread all over the world, we kind of brought a suite of species with us that seem to really like living in our houses,” she said. “Learning about how some of these arthropods have moved all around the globe with humans adds to the evidence of how humans themselves have moved around the globe. For me, it’s starting to paint this bigger picture.”

Trautwein understands if that may not be enough of a reason for most people to put down the fly swatter, but she wants to share her findings with the public to educate them on their own environments.

“If you really look at bugs and take time to get to know them a little bit, they’re just spectacular creatures.” Before Trautwein was a scientist, she was a fine arts major. When she stumbled upon a giant dead wasp on the sidewalk and became fascinated with the shape of its body, using it as a sketch model, she signed up for an entomology class. She switched majors and the rest is history.

Family over a microscopeThis Toronto family opened up their home for the insect census team.
There's An Amazing World Right Under Our Noses

That connection to, and curiosity about, the natural world is something insects can provide for us, says Trautwein. So, before you go home and scour your bookshelves, know that the vast majority of species in any given home are nothing to worry about.

“A diversity of benign roommates is not going to be harmful,” says Trautwein. “This is just part of life on Earth.”

And it’s a part of life that’s actually kind of exciting. Our homes are really just modern nests, and the insects that cohabitate with us — who have adapted to live in our strange, unnatural environments — are daily reminders of evolution. So, while covering your eyes when you see a spider may put you in a state of ignorant bliss, there’s a whole amazing world you’re not seeing right under your nose.

Watch The Great Wild Indoors

“Evolution isn’t something that happened a long time ago — it’s happening now, right in our lives, inside our houses, on our bodies. To be ignorant about it is kind of missing one of the coolest parts of being alive.”

The Wild Canadian Year

Wild Canadian Year

Visit our website to watch the series online, discover extra behind-the-scenes stories and view Canada's nature scenes in 360. Visit Wild Canadian Year

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