After reading this fact, there is a 50% chance you will yawn.
Research shows that 11-week-old fetuses yawn. Yawns become contagious
to people between the first and second years of life. When one person in
a group yawns, over half of the people in the group will yawn within 5
minutes, and the rest will at least be tempted to yawn. Even animals
yawn when they see another animal yawn. The average duration of a yawn
is about 6 seconds, and guys yawn for longer than girls.