Researchers are starting to unravel the mystery surrounding one of the most common behaviors: the yawn. WSJ's Jonathan Rockoff and evolutionary psychologist Dr. Andrew Gallup explain reasons behind the yawn on Lunch Break with Tanya Rivero.
With "My Queue" you can quickly save videos to watch later.
To add an item to your queue just click the sign next to the video.
Once you've added a video visit "My Queue" to start watching!