Anyone who's had the unfortunate experience of finding a dead mouse in the attic or encountering a decomposing deer in the woods knows exactly what it's like. death smells. Although it is a very distinct smell, it is difficult to describe due to the nearly 800 chemicals involved in the process.
It also turns out that our brains have probably evolved to recognize the smell of death and act accordingly, even if we've never encountered that smell before. Once the smell of death reaches our noses, it acts as a “necromon” that alerts us that something has died and that we need to do whatever is necessary to make sure we are not next.
Read more: After death, the necrobiome helps control the circle of life
What does death smell like?
After death, the body goes through many physical and chemical processes, and each of these processes has its own distinct smell. Odors associated with death are attributed to the secretion volatile organic compounds (VOCs) and other compounds such as cadaverine and putrescine.
Cadaverine and putrescine are two compounds responsible for the most recognizable and pungent odors released after death. These compounds, which are not considered VOCs, are formed from the breakdown of amino acids. They are extremely smelly and are what gives the corpse its “rotten” smell.
When it comes to vertebrates, the death process is usually divided into five stages: fresh, bloated, active, advanced and skeletonized. Each of the individual processes produces different volatile organic compounds and odors.
A fresh body will gradually begin to develop an odor as changes in the body's bacteria begin to occur. This smell will be faint and is often said to resemble the smell of almonds, mothballs and candle wax. In the middle three stages – bloating, active and advanced decay – the smell really begins to develop and alert passersby with notes of garlic, gasoline and even freshly cut grass.
How the smell of death helps us survive
Over more than 420 million years, animals have evolved the ability to detect and respond to odors as a means of survival. New research specifically focused on whether people had developed these skills—and it turns out that we have.
Specifically, research has shown that even the slightest hint of putrescine can subconsciously trigger a threat management response in people. When exposed to putrescine in several experiments, people showed an increased sense of alertness, activation fight or flight reaction and increased aggression towards those outside their experimental group. After exposure, people also experienced increased reaction times and an urgent desire to quickly move away from the unseen odor source.
These reactions show that the human brain perceives the smell of death as a warning signal and prepares our body to fight the associated threat.
Is the smell of death dangerous?
Apart from signaling an immediate threat, inhaling the smell of death poses no danger. VOCs and compounds such as putrescine They are toxic to humans only in very large quantities and do not cause any adverse reactions other than possible nausea.
Understanding and recognizing the smells of death was actually quite useful for humans and our ancestors. Even homo ergaster And The man stood up knew the power of the smell of death, often locating their slaughterhouses far from their settlements to protect themselves from scavengers and predators.
In the modern era, the science of the smell of death remains critical to helping train cadaver dogs, which play a vital role in locating missing bodies for police and in post-disaster situations.
Read more: Worms can smell death, and this strangely changes their fertility and fitness
Article Sources
Our authors in discovermagazine.com use peer-reviewed research and high-quality sources for our articles, and our editors review scientific accuracy and editorial standards. Review the sources used below for this article:
:quality(85):upscale()/2025/10/29/924/n/49351082/3d90ba42690282e90bf2c8.18070665_.jpg?w=150&resize=150,150&ssl=1 "Getting Through a Cancer Breakup")
