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There’s something living in the fog. Repeat: there’s something living in the fog.
It may sound like a twisted update to the classic John Carpenter film — or a log line for the new Apple TV horror series “Widow’s Bay” — but these low-hanging clouds are indeed rife with living bacteria, according to new research.
The findings, published in a study in the journal Environmental Microbiology, showed that fog is teeming with so much life that the researchers liken it to a vast aquatic ecosystem unto itself.
“We found that millions of bacteria inhabit… fog droplets,” coauthor Ferran Garcia-Pichel at Arizona State University, told USA Today.
“When you take all of the droplets together, the concentration of bacteria is the same as in the ocean,” he added in a statement about the work.
The presence of bacteria in airborne water droplets isn’t a new revelation in itself. But the work helps elucidate what it is that bacteria do while suspended in fog and other clouds — something that wasn’t clear before — and the impact this has on the broader environment.
“There’s very limited knowledge about what kinds of bacteria are present in fogs, which are like clouds at the ground level,” lead author Thi Thuong Cao, a researcher at ASU, said in the statement.
To peer into this gloomy microscopic realm, the researchers meticulously collected air samples before, during, and after fog events. Since wind can blow fog banks away and confound attempts to get consistent samples, the researchers focused on a specific type called radiation fog that forms on calmer days when the ground cools and chills the air above it, allowing water droplets to condense close to the surface.
After assiduously collecting samples, the researchers found that only one percent of fog droplets contained bacteria. But a thimbleful of these droplets in all packs around ten million bacteria, which is nothing to scoff at.
Some thrived more than others. The population of one bacteria called Methylobacteria, known for devouring simple carbon compounds including pollutants like formaldehyde, increased after fog events. A closer look showed that the bacteria were actively growing and multiplying.
“We observed them under the microscope to see that yes, the bacteria are getting bigger and they’re dividing, so there is growth,” Cao said. “We also found that they’re using the formaldehyde as food to support their growth.”
Garcia-Pichel said this marked a “mindset change” in how we think about fog. “If they are growing,” he said of the bacteria, “then the droplets are a habitat.”
From this habitat, bacteria could be influencing air quality, thanklessly sucking up pollutants. It’s a possibility that might give pause to calls to start collecting fog for drinking water, the researchers say.
“If we harvest fog, we are getting rid of our little friends in the air,” Garcia-Pichel said in the statement. “We don’t know if that’s going to make a big impact or not, but we should be considering that.”
More on biology: Scientists Intrigued by Chunk of Flesh That Refuses to Die After Several Years
