The Play Signal

What it is

Animals that play-fight need a way to show that a bite or a shove is not meant seriously. Robin Dunbar treats human laughter as a modified form of the play calls of apes, and Marina Davila Ross and colleagues found that tickle-induced calls in great apes and humans share a common origin. Steven Pinker argues that laughter still works as a signal that a remark is not a threat.

In effect

In the article on why we laugh, it links human laughter to the panting play calls of other apes.

What it does not say

It is an account of where laughter came from. It does not claim that every laugh signals play.

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