It turns out that the smell of fear is real. A recent article in The New York Times addresses a new study on how the smell of fear effects “family dynamics behavior in Eurasian Rollers–spectacular Jay-sized birds…” What scientists discovered only reinforces the growing evidence that animals–humans included–can smell each others’ fear. The odor (which comes from molecules roughly 10-09 meters across) raises a red flag that can kick our cognitive skills into high gear and help us avoid danger.
“In human studies, the sweat of frightened people has been shown to cause anxiety and heightened vigilance, and even to enhance cognitive performance on tests.” In another study, Karl Grammer of the University of Vienna and his colleagues had subjects take a whiff of underarm pads from women who had either watched a benign documentary or a horror film. They “…rated the latter’s odor as ‘significantly stronger and more unpleasant’ and claimed it reminded them of ‘aggression.’”
Every time a little kid stomps on an ant hill, the disruption causes the bugs to “…produce alarm pheromones that rally colony defenses. If air is blown over the cage of a rat as it receives an electric shock to the foot, rodents downwind of the jolting event react with a full-blown stress response, as if they, too, had been shocked.”
When the skin of an injured minnow (generally 10-02 meters long) secretes what researcher, Karl von Frisch has coined Schreckstoff, or “fright stuff,” all nearby minnows flee as quickly as possible to avoid the same fate.
Injured plants send out similar alarm signals to animals, only they do so through air and soil. (Air molecules are 10-10 meters across with a mass of 10-26 kilograms. There are approximately 10+26 air molecules in a 4m x 3m x 3m room.) When that signal is transferred through the air to other plants, it “…can be construed as evidence of vegetal despair, or at least a reminder that no life form likes being eaten.”
If it is true that we can smell each others’ fear, then remember this the next time you have to look cool, calm and confident in front of someone who intimidates you: it is best stand downwind.