For as long as we've been around, humans have lived with insects. From the earliest cave dwellings to modern-day McMansions, it's been impossible to find a human dwelling that's insect-free. But surprisingly little is known about the bugs thriving in the cracks and crannies of our homes.

So recently, entomologists completed what they say is the first census of the arthropod (a classification that includes insects and spiders) species that live in the typical American home. Assessing 50 houses in the vicinity of Raleigh, North Carolina, they found a stunning diversity of critters.

Here's a graphic summarizing all the types of arthropods they found in the average home. Say hello. These are your true neighbors.

On average, each house hosted 62 different arthropod families, for an average of 93 different species per home. Some homes had as many as 211 species. The authors stress that this is likely a conservatively low estimate, since they only assessed the room in each house that hosted the greatest number of species.

And, yes, every home contained arthropods. Of the 50 houses researchers studied, they found only five rooms that seemed to be bug-free. The paper was published in the journal PeerJ.

Most of the insects in our homes aren't pests

Of the 93 species found, surprisingly few of them were what we'd typically consider pests: cockroaches, fleas, bedbugs, termites, etc. "In fact," the authors write, "we found a relative dearth of typical household pests."

Instead, they mostly found benign flies, spiders, beetles, bees, wasps, and ants.

Which is to say, the vast majority of insects and spiders that live in our homes don't bother us. They may have even evolved alongside us, creating whole, nearly invisible, worlds. And we have yet to fully understand the benefits (insects may clean up our debris, like skin cells and nail clippings) or the downsides (they also may carry disease).

"Biodiversity in urban landscapes is richer than was once thought," the authors write in conclusion, "and we find here that the indoor, manufactured environment also supports more diversity than anticipated."

VIDEO: Tips for a happier home

Be sure to subscribe to Vox on YouTube for more explainer videos