We Yawn All the Time, Yet Know So Little About It

It must be important though, not only do we yawn daily, but we aren't the only animals that do it

Hiya!

If you think about it, yawning is weird. We look ridiculous while doing it, spreading our mouths wide and clinching our eyes shut like a crocodile. Then we make silly sounds as we stretch and exhale simultaneously. Yet, despite its absurdity, yawning feels damn good, and we do it daily.

Yawning is so common that most of us don’t give it a second thought. But actually, yawning is a pretty complex and full-bodied event that’s widespread throughout the animal kingdom. Knowing this, you might think we’d have it all figured out by now, so I was a little surprised to learn that we don’t. The truth is, while yawning has attracted some attention, it largely remains a mystery.

Yawning

Yawning is a trick of our respiratory system, and like sighing, experts have figured out many of the physical aspects of yawning but struggle to explain its purpose. Though there are plenty of theories, far more than the act of sighing has.

Dipak Kumar Dhar, a clinical researcher in the Department of Physiology at the Himalayan Institute of Medical Sciences, published a research paper about yawning in July 2020 in the Journal of Health and Allied Sciences NU. In his abstract, Dhar writes,

“Yawning is a very ubiquitous yet very poorly understood phenomenon. Even though with advancements in science, the scientific community has been able to decode the mechanisms and mysteries behind most of the physiological functions of the body, we still do not have clear answers to this common activity that all of us experience numerous times on a daily basis.”

While a smidge dense, Dhar's research is an impressive breakdown of the knowledge we’ve accumulated since the days of Hippocrates. Most of this newsletter refers to his research.

The Physical Aspect of Yawning

While sighing is a small action, yawning encompasses multiple areas of our body. It takes about six seconds for a yawn to be completed, and includes taking a deep breath, extending your neck, and expanding your jaw while contracting your tongue. Sometimes, we raise and stretch our arms and tense up our arms and/or legs, which makes yawning a coordinated, full-bodied activity.

Even more so, considering yawning often includes dilating our throat, stretching our diaphragm, and even making us teary. The tears caused by yawning are called lacrimation and are thought to be caused by pressure on the lacrimal glands in our eyes — rather than crying, which is caused by an emotional state.

What’s particularly interesting about the actions included in yawning is that the sequence of events stays the same regardless of our surroundings. This in itself isn’t unusual as it’s well known that some of the built-in features of our central nervous system include pre-programmed motor activities that have fixed sequences.

Though Dhar believes the lack of change suggests yawning is “a semi-involuntary act, which once initiated cannot be suppressed, but its manifestations can be modified.” Still, while everything experts have learned much about the physical and biological effects yawns have on our bodies, they still can’t explain their importance. Let alone why we yawn as regularly as we do.

Naturally, where there’s an unanswered question, there’s no shortage of ideas to test them.