Despite advances in science and technology, the human body still holds mysteries. One such enigma is our subconscious ability to sense death. While it may sound like science fiction, researchers suggest this perception may be rooted in biology and scent recognition.

As the body begins to break down after death, it releases a compound called putrescine—a toxic, foul-smelling substance produced during decomposition. Though unpleasant, this scent plays a powerful role in survival behavior, triggering an automatic response in both humans and animals.

According to Arnaud Wisman from the University of Kent and Ilan Shira from Arkansas Tech University, humans subconsciously react to this odor just like animals do: with instinctual avoidance or aggression. Their studies showed that even when people aren’t aware of the scent’s meaning, they still react with discomfort and increased alertness.

This reaction is likely part of an evolutionary survival mechanism, developed to keep us away from potential threats like disease or danger. Putrescine may not be consciously linked to death or fear, but it creates a shift in behavior nonetheless.

Interestingly, this isn’t the only example of scent influencing behavior. Sex pheromones are another potent force, known to draw individuals together for reproduction.

However, where pheromones trigger attraction, putrescine prompts repulsion and heightened awareness.

As Wisman and Shira explain, scent affects our emotions, decisions, and preferences—even when we’re not consciously aware of it.