# Nonverbal Gestures **URL:** \ **Category:** Factual Questions\ **Created:** [August 30, 2017, 2:49am UTC](https://boards.straightdope.com/t/nonverbal-gestures/795073 "2017-08-30T02:49:56Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![lastinline](https://avatars.discourse-cdn.com/v4/letter/l/cc9497/32.png) [@lastinline](https://boards.straightdope.com/u/lastinline)\ **Post date:** [August 30, 2017, 2:49am UTC](https://boards.straightdope.com/t/nonverbal-gestures/795073/1 "2017-08-30T02:49:56Z")
So, hello and everything. My question, which I haven’t found on this site, which I do enjoy, is: What is the origin of nonverbal gestures? Specifically handshakes, the thumbs up, smiling, and laughing. Ostensibly, these gestures seem aggressive. Gorillas think eye contact is threatening, or so I am told. So How did grabbing someones hand, bearing one’s teeth and barking at them become signs of trust? For the record, yes, I have read Eric Idle’s The Road to Mars ---
**Author:** ![Alessan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/alessan/32/465_2.png) [@Alessan](https://boards.straightdope.com/u/Alessan)\ **Post date:** [August 30, 2017, 5:20am UTC](https://boards.straightdope.com/t/nonverbal-gestures/795073/2 "2017-08-30T05:20:12Z")
Smiling and laughing are, I believe, instinctive - we do them because we’re hardwired to, and we react to them in certain ways because we know that people do them involuntarily. Handshaking is a cultural thing, but for most mammals, non-violent physical contact is an expression of trust - like a cat sitting on you lap. The thumbs-up thing is just modern colloquial sign language. Most people throughout history wouldn’t understand what it means. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [August 30, 2017, 12:49pm UTC](https://boards.straightdope.com/t/nonverbal-gestures/795073/3 "2017-08-30T12:49:49Z")
I’ve heard that the origin of the handshake is that it was a way of demonstrating that neither person had a weapon in their dominant hand (assuming that everyone involved is right-handed, of course). This might just be folk etymology, though.