Yawning serves a dual purpose in regulating the body's temperature associated with sleep and wakefulness. In the evening, yawning occurs as the body and brain prepare for sleep, facilitating a decline in temperature during the onset of sleep. Conversely, in the morning, yawning helps modulate the rapid increase in temperature as the body transitions from sleep to wakefulness. The frequency of yawning aligns with these critical temperature changes, highlighting its role in managing our physiological states during these transitions.