THE HIDDEN WORLD

WHAT’S LEFT OF THE PLANET TO DISCOVER? SCIENCE AND CHILDLIKE WONDER WOULD SUGGEST ... A LOT.

They are plump, charismatic and nearly microscopic, with eight legs and a smushed face. It is easy to become inordinately fond of them. It is remarkably unusual for something nearly indestructible to be so cute. The story goes like this: Dr. Kazuharu Arakawa, of the Institute for Advanced Biosciences at Keio University, plucked some moss from the parking lot in front of his apartment building and discovered something new: Macrobiotus shonaicus.

“I routinely survey tardigrade ecology by screening moss samples all around the town,” he writes, after I ask why he was gathering samples in his parking lot. “So I was actually not looking for a new species.” But why moss? Many tardigrade species were discovered from mosses and lichens, “thus any cushion of moss seems to be interesting for people working on tardigrades.” Tardigrades are technically aquatic, and need water around their bodies so they don’t dry out, though drying out is not always a death sentence. Tardigrades that were dehydrated and exposed to the vacuum of space and solar radiation for 10 whole days have returned to earth, been rehydrated, and gone on to produce viable offspring.

I ask him what it feels like to discover something new, and his answer reflects the careful, continuous process of inquiry that typifies the scientific method. “That is my job as a scientist: to discover something new, so it is an ordinary part of my life. And the moment of discovery is not as exciting as popular image portrays, but rather a continuous process.” Arakawa walks me through the process of approving a new species of tardigrade, starting with the early days of seeing if it makes tardigrade babies. Once the eggs hatch, the research team waits for the second generation, at which point they move on to DNA sequencing and compare its morphology to other previously described species using electron micrographs. After all of that is completed, “we write the paper, and seek the judge of multiple referees, and the species is finally approved to be novel.” This whole process took the researchers about two years. “I was surprised to find the new species at such a familiar place,” he admits. Look closer, and you’ll find that unknowns are everywhere. We are, in fact, covered in them, something that Dr. Rob Dunn, a professor of in the applied ecology department at North Carolina State University, is quick to point out. “Every morning, each of us wakes up covered in species no one has ever studied.”

Dunn would know. Previously, his research team sampled the microbial life from 60 belly buttons and found 2,368 bacterial species, of which 1,458 might be new to science. And these days, Dunn and his team are turning their formidable powers of inquiry to something you’ve probably never considered: the common showerhead.

“To put it simply, showerheads are a novel habitat that favours the growth of communities of microbes that sometimes seem to make us sick and may, sometimes, make us well.” Beyond that, little was known about what lives up there and why. “Collectively then, we all look up into the spray and bathe beneath a rather vulgar sort of mystery. I guess the better question is, ‘Why would someone, in knowing this, not study showerheads?’”

Before we go any further into the great secrets of the microbial life that surrounds us, let me provide a gentle reminder that the omnipresence of microbes is okay. “In a small proportion of people, particularly those that are immunocompromised, the microbes in showerheads can potentially make us sick,” Dunn explains. “But the important thing to know here is that it isn’t the presence of microbes that makes us sick, but rather the specific mix we have. All tap water and all bottled water is full of microbes. All showerheads are full of microbes. The question is: which ones?”

Humans have invented all kinds of new habitats for wildlife inside our homes, from toilets to showerheads to whatever is currently living inside the unwashed coffee mugs that haunt our kitchens. Dunn points out that we created these spaces without really thinking about which microbes these habitats favour. The question isn’t if there are microbes around, the question is: which ones?

“Repeat after me, there are microbes everywhere the vast vast vast vast vast vast majority of which are beneficial or harmless.” And now we need to look at how our actions may favor problematic species. “My personal hypothesis is that it is probably better to have a shower head with more biodiversity,” rather than one with only a few resistant and potentially harmful microbes. “But,” Dunn concludes with the sort of professionally resigned uncertainty that fuels scientific progress and occasionally exasperates the lay public, “we’ll see.”

It is easy for me to blow through my day focused on the minutiae of modern life, but then I remember that there are people out there sampling moss in parking lots, marvelling at the ecology of our homes, crouching in city streets to draw blood from pigeons. There is the way I rush when I take the trash out and there is the way that my child follows behind, checking under rocks for worms and chirping about what she sees in the sky. The idea of the great undiscovered is often relegated to the ocean floor, given how little we know about it and how foreign it seems. But the undiscovered is everywhere.

My daughter’s curiosity is spring-green, boundless, and wildly contagious. Yesterday alone she asked for a detailed explanation of where ants come from, threw an appreciation party for the sunset, wanted to discuss how the sky becomes pink, found half of a robin’s egg in the yard and set about re-seeding the yard with flowers, announcing her wish of “more dandelions” each time she blew their wispy seeds into the wind. She reminds me that the great unknown is everyday. For her, wonder is not only a joy, it is perfunctory; a function of being alive. It reminds me that we humans still have so much to learn.

As Dunn so succinctly surmised, “To figure out the stories of those species is wonderful – but also humbling. It gives you good chills, but also a kind of gape-mouthed awe at the reality that we are still so damned ignorant. Biologically, we are still in the dark ages.”