Why do Human beings spits whenever they smelled something bad?

The disgust response of wrinkling the nose, opening the mouth, exposing the tongue, spitting, and gagging/vomiting is a reflex meant to clear noxious and potentially dangerous substances from the body (or prevent their ingestion in the first place).

When you smell something rotten or foul, you have inhaled through nose and in distress exhale some of it through mouth. This leads to particles of the substance leave through your mouth and your brain takes things that smell bad as tastes bad and hence makes us spit!

https://imgflip.com/memegenerator/43049060/Stank-face
https://www.quora.com/Evolutionary-Psychology-Why-do-people-in-general-spit-or-vomit-if-they-smell-something-bad

                    Hello my fellow Steemians... 

I've always wondered why people feel like spitting whenever we smelled a bad odor, so I decided to do a little research as soon as I got off work so I can share it with the Community and my son Omarion. I hope this post helps to give a little more understanding of why we naturally gag or spits whenever we smell something bad.

                   From my understanding... 

"There's always saliva in our mouths, so whenever we sense an unpleasant odor, the saliva that's already in our mouths gets sour and everything in our cells wants to get rid of it being that we only rather breathe fresh air."

                  Danger signal

They say it takes more than a mere whiff of an offending odour to trigger the response.
Smells so irritating they make you cough or gag may act on a single type of cell in the nose that senses caustic chemicals and warns the brain of potential danger, US researchers say. Scientists thought such smells acted directly on nerve endings in the nose
http://www.nairaland.com/2788257/why-spit-when-perceive-odour
http://www.abc.net.au/science/articles/2008/03/05/2180489.htm

Hope you guys enjoyed as much as I did... Thanks to the Steemit Community and please don't forget to UpVote and Follow.
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