Your body is made up of many, many systems, too: diaphragm, lungs, capillaries, nervous system, and heart, just to name a few. When you exercise, your muscles require oxygen, which requires your heart to pump faster, which requires your lungs to diffuse oxygen into your blood at a higher rate. But when you begin to think about your body as a ‘system of systems,’ you begin to wander down a seemingly endless rabbit hole of ‘subsystems,’ all of which are endlessly fascinating.
For example, when you look at a diagram of the mammalian respiratory system, it appears to be a rather poorly designed setup. Every food and liquid you consume must pass dangerously close to the trachea (the air tube that leads to your lungs) before making its way down your esophagus and into your stomach. The back of your throat is a rather terrifying danger zone: with every swallow there is a potential for something to go terribly wrong. If a piece of food becomes lodged in your trachea (instead of going down the esophagus) then your oxygen supply is cut off, which would lead to suffocation by choking. Liquids pose a similar threat: if enough fluid finds its way into your lungs, the result is drowning.
And yet you eat and drink all the time without much trepidation. How does it work?
At the top of your trachea, immediately behind your tongue, just above your voice box (larynx), there is a small cartilage called the epiglottis. Swallowing triggers a series of muscles that push your larynx up against the epiglottis, closing off the airway to the lungs and ‘redirecting’ all incoming substances (food and liquids) down the esophagus (and into the stomach). The epiglottis is like a bypass switch. Thus, breathing and swallowing must happen in perfect synchronization, since opening the trachea while swallowing would risk allowing the incoming food or drink to “go down the wrong pipe”. Such an error, if serious enough, could lead to some potentially lethal scenarios for the respiratory system. Considering the number of times this mechanism repeats over the course of a life time, its success rate is truly stunning (although, unfortunately, it only takes one devastatingly careless ‘misfire’ to incite a fatality).
Our ability for phonation (speech) means that our oxygen intake must be temporarily hampered as the larynx constricts the vocal folds behind the epiglottis. Speech, then, must cooperate with the respiratory system as a whole. Among mammals, we humans are especially flirtatious with danger, because we regularly combine eating, breathing, and talking. (Perhaps the average dinner party is much more hazardous than we give it credit for.)
As is often the case, exploring the anatomy of an organism introduces us to the unsung heroes of existence and survival. Every time you swallow you are dependent on your epiglottis — this rather unsightly little flap of cartilage — to keep you from drowning or choking. But you probably do not think about your epiglottis often (if at all) precisely because it works so well.
When you adopt ‘systems lens,’ you begin to see things different. You might discover that some of the most amazingly ‘well coordinated’ processes are just about invisible. Perfect synchronization might be virtually inconspicuous. Sometimes a part of a system that is vital for survival can easily be be taken for granted, much like the epiglottis, until something goes wrong.