Why Are We Ticklish?

SciShow series Quick Questions host Hank Green explains the science behind why humans are ticklish. Green also explains that the concept of tickling actually breaks down into two parts, knismesis and gargalesis, and suggests tickling may be a form of self-defense training.

Description:

What’s up with ticklishness? And are other animals ticklish, too? Quick Questions has the answers!

 

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