Herb Silphium | First Contraceptives Of Ancient World
Back in times, silphium was used in cooking; the sap of the plant was also used as a medicinal treatment as a birth control. Sil...
Yawning excessively happens when the act of yawning occurs frequently or in close succession. When you yawn, your mouth opens and you take a long and deep breath. It may also be triggered by viewing someone else yawning.
The exact reason of human yawn is unknown but common causes are here:
Psychological or emotional causes
Excessively yawning may be the sign of sleep disorder like sleep apnea and may also occur in the presence of heart disease.