Best posts about this topicLoading . . .
Yawning (oscitation) most often occurs in adults immediately before and after sleep, during tedious activities and as a result of its contagious quality. It is commonly associated with tiredness, stress, sleepiness, or even boredom and hunger. In humans, yawning is often triggered by others yawning (e.g. seeing a person yawning, talking to someone on the phone who is yawning) and is a typical example of positive feedback. This "contagious" yawning has also been observed in chimpanzees, dogs, cats, birds, and reptiles, and can occur across species. Approximately 20 psychological reasons for yawning have been proposed by scholars, but there is little agreement on the primacy of any one.
No signin required
Sussle is the first, open visual encyclopedia. Anyone can use it.
It has beautiful images and viral videos that are way more fun than reading all the text in traditional encyclopedias.
Just click on the red module above.