As we walk through our daily environments, we’re surrounded by exotic creatures that are too small to see with the naked eye. We usually imagine these microscopic organisms, or microbes, as asocial cells that float around by themselves. But, in-reality, microbes gather by the millions to form vast communities known as biofilms.
Natural biofilms are like miniature jungles filled with many kinds of microbes from across the web of life. Bacteria and archaea mingle with other microbes like algae, fungi, and protozoa, forming dense, organized structures that grow on almost any surface. When you pad across a river bottom, touch the rind of an aged cheese, tend your garden soil, or brush your teeth, you’re coming into contact with these invisible ecosystems.
But why do microbes build such complex communities, when they could live alone? For one thing, microbes living in a biofilm are rooted in a relatively stable microenvironment where they may have access to a nutrient source. There’s also safety in numbers. Out in the deep, dark wilderness of the microbial world, isolated microbes face serious risks. Predators want to eat them, immune systems seek to destroy them, and there are physical dangers too—like running out of water and drying up. However, in a biofilm, the extracellular matrix shields microbes from external threats.
Biofilms also enable interactions between individual cells. When microbes are packed against each other in close proximity, they can communicate, exchange genetic information, and engage in cooperative and competitive social behaviors.
So the next time you brush your teeth, bite into that cheese rind, sift through garden soil, or skip a river stone, look as close as you can … imagine the microbial jungles all around you … waiting to be discovered and explored.
Throughout history, most currency (including the US dollar) was linked to valuable commodities, and the amount of it in circulation depended on a government’s gold or silver reserves. But after the US abolished this system in 1971, the dollar became what is known as fiat money, which means it is not linked to any external resource but instead relies solely on government policy to decide how much currency to print.
The value of money is determined by how much (or how little) of it is in circulation. But who makes that decision, and how does their choice affect the economy at large? Join us on a trip into the United States Federal Reserve, examining how the people who work there aim to balance the value of the dollar to prevent inflation or deflation.
1. If the total amount of currency circulating increases faster than the total value of goods and services in the economy, each individual piece will be able to buy a smaller portion of those things than before. This is called inflation.
2. On the other hand, if the money supply remained the same while more goods and services were produced, each dollar’s value would increase, in a process known as deflation.
3. So which is worse? Too much inflation means that the money in your wallet will be worth less tomorrow, making you want to spend it today. While this stimulates business, it also encourages overconsumption or hoarding commodities like food and fuel, raising their prices and leading to consumer shortages as well as more inflation.
4. But deflation makes people want to hold on to their money. The decrease in consumer spending reduces business profits, which leads to more unemployment and a further decrease in spending, causing the economy to keep shrinking.
So most economists believe that while too much of either is dangerous, a small consistent amount of inflation is necessary to encourage economic growth. The Fed uses vast amounts of economic data to get the numbers just right in order to stimulate growth and keep people employed without letting inflation reach disruptive levels.
Microbial communities provide humans and other species with tangible and sometimes even delicious benefits. Microbes make up a major fraction of the biomass on Earth and play a critical role within the global ecosystem that supports all larger organisms, including us. They produce much of the oxygen we breathe, and are recruited to clean up environmental pollution like oil spills, or to treat our wastewater. Not to mention, biofilms are normal and flavor-enhancing parts of many of the foods we enjoy, including cheese, salami and Kombucha.
If you tried to pay for something with a piece of paper, you might run into some trouble. Unless, of course, the piece of paper was a hundred dollar bill. What is it that makes that bill more valuable than other pieces of paper?