Yawning is a universal phenomenon observed in many vertebrate species, from wolves to parrots. Of course, we also know it well in humans, which appears from a very early age. But why do we start yawning when we see someone else yawning? Whether it's supplying oxygen to the brain, regulating body temperature, or relaying social signals, there's no shortage of speculation about the true purpose of yawning. The most widespread idea is that yawning increases oxygen delivery to the brain, but this has not been scientifically confirmed. According to another explanation, it helps maintain interest, but there is no consensus on that either.
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However, the relationship between yawning and circadian rhythms, such as our biological clock, is certain. The majority of yawning occurs during rest and is usually centered around the wake and sleep stages. Specifically, it occurs when the body is less alert, such as when it is working to digest a meal
Astrid Thibault Guichon, researcher at Ingénieure et Enseignemente A Science Alert Online scientific portal.
Yawning as a tool for communication?
Although the causes of yawning have not been fully verified by experts, its “contagious nature” leads to important discoveries in various disciplines, whether in the field of biology or social psychology.
Yawning may play an important role in social interactions, as observed for example in ostriches, which are used to synchronize group behavior. Like humans, they often yawn when transitioning from being awake to resting or vice versa. Yawning can then signal changes in activity or alertness, ensuring that all group members are alert or at rest at the same time, increasing group safety and maintaining the group's rhythm.
Astrid Thibaut-Guichon noted, adding that the prevalence of yawning is primarily a human trait, with a few exceptions, such as chimpanzees or lemurs.
