Pheromones in Humans and Animals

Pheromones are used by almost any animal you can think of. Unrelated species can use the same pheromone molecule and mammals can use them for physiological responses.

What is a pheromone?

A pheromone is a sensory stimulation from a group of molecules that pass through the VNO. They are used as chemical messengers to attract the opposite sex.

Some common behaviors that pheromones had been associated with playing a role in our sexual relations and courtship, fighting, social communication, and maternal caregiving. The investigation of pheromones began in the sixties and seventies with their discovery and insects and eventually in other animals like mammals, reptiles, and eventually humans.

Scientific interest eventually led to the creation of a journal called pheromones fitting well with many theories of behavior at the time, like stimulus-response conditioning. The concept of pheromones became an attractive unconscious explanation for all sorts of animal. And eventually, human behaviors want to tell rivals that this is your territory.

You just release a pheromone, want, attract someone of the opposite sex, you release a pheromone. And while millions of dollars have been invested in, spent on not only research but marketable pheromone, unrelated products, many scientists question the existence in mammals and humans at all.

How They Work

I’m going to be detailing how pheromones are proposed to work, uh, and the evidence for and against their functionality in human behavior. So how do they work? Well, the vast majority of research done on pheromones has done in invertebrate species, mostly insects in insects.

Pheromones are produced in a series of glands that vary depending on the species and are received through receptors that send signals to the brain to alter their behavior from one insect to another. Pheromones are usually classed to do four broad categories.

These are releasers that elicit immediate specific behavioral responses, primers that affect hormone levels during development, signalers, which provide information about the sender and modulators that alter or synchronize body functions between individuals.

The direct causal nature of pheromones and insects, and the fact that insects are relatively simple creatures means the scientists can reliably get insects to aggregate, mate, defend our territory, etc. Just by isolating and administering these pheromonal compounds. The actions of pheromones in insect behavior is so robust that they’re often used for pest control. Learn more at

Pheromones in Humans and Animals

Pheromones are chemical scents cued by members of the opposite sex within a species to the alter the behavior of others. This can be in the form of sexual attraction, aggression, dominance, and other social cues. They are detected by the vomeronasal organ which is less active in humans than it is in other mammals.

Human behavior with pheromones

How can males and females trigger diffract sexual behavior under the influence of human pheromones? Experiments have shown a male will attack another male and a female detecting a male will trigger mating behavior instead. In a very simple behavior experiment, we observed the receptivity of the female. As you can see the female was behaving very strangely in the presence of androstenone. While they are displaying typical sexual behavior it was indeed due to the influx of pheromones. Learn more at

Courtship Behavior

What is happening specifically regarding the detection of pheromones? How is this information processed within the brain and how are specific behaviors generated? How is the quality of the pheromone information perceived? There are two systems, the vomeronasal system on one hand and the main olfactory system on the other.

The assumption for a very long time was that the VNO was specialized in the detection of pheromones and the olfactory system was specialized in the detection of odors and chemicals. This notion came from scientific experiments were people had surgically abated their olfactory system and this led to impairment of odor detection.

This led to defects in mating and sexual behavior. In contrast, pheromone information that is detected by the vomeronasal organ is processed by an independent pathway. To make sense, the area is that involved would be responsible for the cognitive detection of androstenone and androstenol.

How Pheromones Are Detected Through The VNO

The VNO is more involved in the process of pheromonal signals and sexual behavior. This is all very logical at the molecular level. The pheromone odor is banded to the VNO to an electrical signal. In the vomeronasal organ, we do not find any cyclic nucleotides. At the molecular level pheromones provide a chemical message to influence behavior for sexual intercourse.