Some biologists (lumpers) use broad definitions to group organisms. Others (splitters) believe in using higher resolution. Fungi and bacteria, claiming half of the kingdoms that comprise life as we know it, are usually lumped under the marquee of "microbes." This is lumping on an epic scale. As a mycologist (I study fungi) and a father, here are two reasons why I think we should stop being such lumpers and dive into the details instead.
First, splitting microbes makes sense for environmental science. I can remember being a student and visualizing microbially driven processes as inputs/outputs through a swarm of cells on a microscope slide. Then I met a fungus that was bigger than me. A single Armillaria ostoyae fungus in Oregon's Blue Mountains was shown in this research to weigh more than a blue whale and be more than 2,000 years old. This is a fungus with a personality, and it is still rotting tree roots and posing for aerial photographs. For reference, this research suggests there are 2,000 bacterial species in an average 0.5 grams of soil here in Minnesota. We are lumping mountains with molehills.
What happens if a widely distributed fungus with a unique function, such as degrading spruce lignin in boreal forests, goes extinct? If, when we think "fungi," we think of a swarm of thousands of species of microbes, we might assume a robust community with functional redundancy: No problem. But I would argue that single species can drive large environmental processes in low-diversity systems like the boreal, and extinction of a single species could be a problem. This may justify "red listing" threatened fungi as folks do in Scandinavia and elsewhere.
Second, there is value in knowing species as individuals. Yes, we fight off particular bacterial diseases, and certain isolates offer unique biotechnological promise. But also consider "Ötzi the Iceman," found frozen in the Italian Alps in 1991. The story goes that Ötzi was out for a walk about 5,000 years ago after having a meal of goat meat. He never made it back to camp. He froze to death with a fire-starter kit at his side (irony can be painful) containing the tinder polypore mushroom Fomes fomentarius. As tinder for starting fire it was a life-saver, and if you didn't know the fungus, you didn't get your fire going. This type of working knowledge of biota has withered since industrialization, and many of us want it back.
"Microbes," especially fungi, are a good place for you and your kids to start reclaiming that knowledge. It's the next big scientific frontier, and you usually don't have to stray too far from the sandbox to make hands-on discoveries. So dive in!
Jonathan Schilling is an associate professor in the Department of Bioproducts & Biosystems Engineering (College of Food, Agricultural and Natural Resource Sciences) and a resident fellow at the Institute on the Environment, where he is collaborating with forest ecologists, economists and others to improve understanding of how fungi and environmental protection can benefit each other.