Why Do We Yawn?

Everyone yawns, but no one knows why. We start when we are in the womb, and we do it through old age, but the purpose and survival value of yawning remain a mystery.

There is no shortage of theories but a dearth of experimental proof that any of them is correct. "The lack of experimental evidence is sometimes accompanied by passionate discussion," said Dr. Adrian G. Guggisberg, the lead author. Hippocrates proposed in the fourth century B.C. that yawning got rid of "bad air," and increased "good air" in the brain. The widely held modern view of this theory is that yawning helps increase blood oxygen levels and decrease carbon dioxide. If this were true, Dr. Guggisberg writes, then people would yawn more when they exercise. And people with lung or heart disease, who often suffer from a lack of oxygen, yawn no more than anyone else.

​There are two kinds of failure – but only one is honorable

Malcolm Gladwell teaches "Get over yourself and get to work" for Big Think Edge.

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  • Learn to recognize failure and know the big difference between panicking and choking.
  • At Big Think Edge, Malcolm Gladwell teaches how to check your inner critic and get clear on what failure is.
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Why the ocean you know and love won’t exist in 50 years

Can sensitive coral reefs survive another human generation?

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  • Coral reefs may not be able to survive another human decade because of the environmental stress we have placed on them, says author David Wallace-Wells. He posits that without meaningful changes to policies, the trend of them dying out, even in light of recent advances, will continue.
  • The World Wildlife Fund says that 60 percent of all vertebrate mammals have died since just 1970. On top of this, recent studies suggest that insect populations may have fallen by as much as 75 percent over the last few decades.
  • If it were not for our oceans, the planet would probably be already several degrees warmer than it is today due to the emissions we've expelled into the atmosphere.
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Image source: Topical Press Agency / Getty Images
Politics & Current Affairs
  • Though we know today that his policies eventually ended the Great Depression, FDR's election was seen as disastrous by some.
  • A group of wealthy bankers decided to take things into their own hands; they plotted a coup against FDR, hoping to install a fascist dictator in its stead.
  • Ultimately, the coup was brought to light by General Smedley Butler and squashed before it could get off the ground.
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Health care: Information tech must catch up to medical marvels

Michael Dowling, Northwell Health's CEO, believes we're entering the age of smart medicine.

Photo: Tom Werner / Getty Images
Sponsored by Northwell Health
  • The United States health care system has much room for improvement, and big tech may be laying the foundation for those improvements.
  • Technological progress in medicine is coming from two fronts: medical technology and information technology.
  • As information technology develops, patients will become active participants in their health care, and value-based care may become a reality.
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