Why do we cry? The three types of tears - Alex Gendler
- 6,744,077 Views
- 7,061 Questions Answered
- TEDEd Animation
Let’s Begin…
Whether we cry during a sad movie, while chopping
onions, or completely involuntarily, our eyes are constantly producing tears.
Alex Gendler tracks a particularly watery day in the life of Iris (the
iris) as she cycles through basal, reflex and emotional tears.
Create and share a new lesson based on this one.
Additional Resources for you to Explore
Check out these microscopic images of tears. So beautiful!
The lacrimal apparatus works to produce tears that are needed to wet the front of the eye and flush debris from the ocular surface.
Many animals yelp or cry out when they're in pain. But as far as scientists can tell, we humans seem to be the only species that shed tears for emotional reasons. Scientists who study evolution say crying probably conferred some benefit and did something to advance our species — because it's stayed with us. Read more here.
A supporter of the Spanish team cries while watching the World Cup final soccer match, which Spain won 1-0. Crying may have evolved as a signal to those who were in close physical proximity to us, but it also adds a powerful dimension to interpersonal communication:

Women do it 64 times a year, men just 17. Actors and politicians do it on demand. But why does crying happen in the first place? John-Paul Flintoff learns that even scientists are still guessing.

The lacrimal apparatus works to produce tears that are needed to wet the front of the eye and flush debris from the ocular surface.
Many animals yelp or cry out when they're in pain. But as far as scientists can tell, we humans seem to be the only species that shed tears for emotional reasons. Scientists who study evolution say crying probably conferred some benefit and did something to advance our species — because it's stayed with us. Read more here.
A supporter of the Spanish team cries while watching the World Cup final soccer match, which Spain won 1-0. Crying may have evolved as a signal to those who were in close physical proximity to us, but it also adds a powerful dimension to interpersonal communication:

Women do it 64 times a year, men just 17. Actors and politicians do it on demand. But why does crying happen in the first place? John-Paul Flintoff learns that even scientists are still guessing.


TED-Ed
Lesson Creator
New York, NY
It is sometimes difficult to see how or why certain human physical characteristics would have evolved. One theory about emotional tears is that they signal your emotional state to others. Another says that they help to stabilize your mood by releasing stress hormones.
Create and share a new lesson based on this one.
More from Getting Under Our Skin
9,051,114 Views
151,635 Views
2,432,646 Views
280,681 Views