Biodiversity, Down and Dirty
A loss of bacterial diversity on our skin and in our environment is taking its toll
It is the characteristic thumbprint of human dominance on Earth: take a complex system and simplify it. We do this in our yards when we replace hundreds of "weeds" with a single species of lawn grass. We do this in our agriculture fields when we plant three hundred acres containing only soybeans, corn or wheat. We do it in our forests when we selectively eliminate animals that are predators like ourselves and trees we can sell for profit.
All these choices we make result in a loss of biodiversity, and all too many of us could care less. "What has a dandelion done for me lately?" "What good is a chipmunk, I mean, really?" The presence of life forms other than and different from our own is frankly not very high on the list of desirable things most people insist on for their children's future. But it should be.
The loss of biodiversity matters, from the human gut to the human skin to the human home and the home's landscape. It is seeming to matter more than we thought, if by we you mean everybody but an assortment of ecologists who have suspected this all along but now are gathering evidence.
Rob Dunn, writing in Anthropocene Magazine, looks at this topic in an excellent article titled "Letting Biodiversity Get Under Our Skin." It explains that our health may depend as much on keeping around us the high diversity of "good" or seemingly-neutral bacteria as it does on eliminating the bad ones. We came, we saw, we cleaned. Cleaning almost always means "to kill."
There are costs to a life, too deep-scrubbed and squeaky-clean:
Half a dozen theories—biophilia, nature deficit disorder, the deficiency theory of disease, the dilution effect, and more—describe the ways in which the loss of a connection to biological richness might cause us to ail.
Less biodiverse systems—be they grasslands, forests, or the biomes of tiny life on our skin and in our guts—are less resilient and at greater risk of invasion (whether by pathogens or weeds) than more diverse systems.
Country kids are exposed to more life, be it cows, chickens, or—as Strachan suspected—the microbes that cows and chickens harbor. It was a wild, speculative idea. It also increasingly appears to have been right.
Homo charges ham-fisted through a scary world we don't understand very much at all, and we shoot at anything that moves. If it truly is all about us, then why have this ugly mix of unnamed and unknown creatures about us? Look at how our crippled immune systems increasingly fail to protect us:
We kill the life most susceptible to our weapons. In their place grows a more depauperate and resistant wildness—nature despite us, not for us—a jungle of potentially dangerous weeds. We are reducing diversity in our daily lives, even on our bodies, in exactly the same way that we are reducing it in the world. We manage our own flesh as we manage the earth.
As we rebuild after the most recent (but not the last) pandemic--itself a product of lost habitat and biodiversity in rural China--it is crucial that we come to understand the basic science of ecology--the principle that in nature, you cannot do only one thing. The current, willful science illiteracy must be reversed if we are to nurture nature so that it supports us.
We are good at killing species around our houses and on our bodies, but far less practiced at cultivating them.
The article describes studies currently underway to determine how the mix of microbes in and around us, in urban and rural homes, keeps us well or makes us sick. The jury will be out for some time, but we know the right questions to ask, and biodiversity is a much bigger issue even than the disappearance of sexy big mammals and exotic cacti. It starts with our skin. The article concludes:
Our conscious minds and progressive societies seem slow to realize this, but our subconscious immune systems may have known it all along. We will be measured by our immune systems and our microbes, which in their function or dysfunction seem to record the richness of our lives.
Without any logic or rational thinking, I have never used anti-microbials and I never have washed my hands very often. I have a daughter-in-law that keeps a dust free house because of her allergies and her son has always been sick.