The Best Laid Plans are Bound to Grow your Rye

Photo Credit inhabitat.com

There are three certainties in life: death, taxes, and the amazing ability of natural selection to produce surprising results. From clownfish making a home in the tentacles of venomous anemones to the poop-eating fly, every niche gets filled and every resource gets used. But what happens when us notoriously destructive humans come into the picture? It turns out we’re not only destroying habitats by building houses, we’re also creating new ones in some pretty surprising places. Who knew your dishwasher could be so cozy?

            Before we venture into what’s colonizing our kitchens, let’s explore the idea of ecological niches and how they drive evolution. In simple terms, and ecological niche is any living thing’s role in its community. The waitress in your community serves you lunch, but also occupies a home, takes the bus to work, and buys bread from the bakery. Her niche in the community is not only what she does, but how she contributes to what everyone else does and where and when she moves around. Everyone has a niche: doctors, homeless people, cashiers, teachers, raccoons, moths, viruses, and fungi.

            Everything in nature occupies a specific ecological niche. If too many organisms have the same role (fill the same niche) in a community, the competition for resources makes it hard for them to make ends meet. Picture a neighbourhood with too many piano teachers: there are just not enough students (and paying parents) to go around. If one of them starts teaching children’s art classes, however, they can collect cash from a whole new set of parents. By using the community resources (ie. bored school kids) in a new way, the various teachers are able to coexist. This is essentially what happens in nature and is one of the major forces driving evolution.

            The pressure to use all available resources results in species that live in some pretty extreme environments. Think of the tubeworms in the boiling ecosystem around hydrothermal vents, fish in acidic caves, and black yeast growing in your dishwasher. That’s right, ecological niches can be man-made too, and some can be just as extreme as those found in nature. The dishwasher, for example provides an environment with intermittent hot temperatures, tons of moisture, and high pH (due to the dish soap). What it also provides is lots of food; after all, that’s what we’re trying to clean off the dishes in the first place. This valuable resource is not accessible to many organisms, but the few that can tolerate the harsh conditions can set up shop and thrive in this newly created household niche.

            Lots of spaces in our towns, cities, and especially bathrooms are great new habitats for the homemaking. Unfortunately for us, some of our microscopic roomies can prove pretty temperamental. Antibiotic-resistant bacteria in hospitals are the result of an environment with lots of these chemicals. Heat-tolerant and potentially harmful black yeast are evolving to fit a very family-adjacent niche thanks to our hatred of hand-washing dishes.

            You can’t control everything, humans. The very areas we create as unlivable will always be taken advantage of by something that thrives in just those conditions. Every once in a while we have to take pause and remember: evolution is one bad grabba-jabba!