The flehmen and the organ of Jacobson or vomeronasal in the cat

Have you ever seen your cat smell something, then open your mouth and stand still for a few moments with your mouth open? That kind of grimace is technically called flehmen, and at that moment your cat was using Jacobson’s organ or vomeronasal organ to analyze pheromones. We see in this article in detail what this means.

The flehmen

The reaction of the flehmen is a typical grimace that the cat performs by slightly opening the mouth and slightly raising the upper lip, to uncover the teeth. The cat freezes for a few moments, staring at the void, as if it were stopping.

This grimace of the flehmen occurs after the cat has smelled something, which can be a surface, a liquid, a tissue, to then move away from it and stop at this strange position. Maybe it will have happened to you that your cat does this expression after having smelled your feet, and you will believe that it may be a disgusting expression.

In reality with the face of Flehmen the cat is not smelling with normal smell, and is not analyzing an odor. Instead, it is analyzing pheromones, molecular signals that contain valuable information through which cats and other animals communicate. Read also: Cat pheromones, what they are and what they are for.

Through the Flehmen the cat directs the pheromones towards a particular organ that has behind the palate, which is called the vomeronasal organ or Jacobson’s organ, which is specifically designed to analyze these particular molecules.

The cat is not the only animal to use the flehmen, but it is a grimace characteristic of many felines like tigers and lions but also of many mammals such as the horse, giraffe, goats, zebras, llamas and bisons.

The grimace of the Flehmen is very often used by animals in the reproductive period, to analyze the sexual signals in the female, not only between animals of the same species, but also between animals of different species, when analyzing the reciprocal urine.

But how are pheromones analyzed after the cat or animal made the face of the flehmen? Let’s see what Jacobson’s organ is and what it is for.

Vomeronasal organ or Jacobson’s organ

The vomeronasal organ is also called a jacobson organ because Ludwig Jacobson discovered it in 1811, although he had already been identified by Frederik Ruysch.

It is an organ located in the palate, behind the upper incisors, under the nasal cavity, and connected to the palate through the vomeral pits. Jacobson’s organ is also present in humans and other animals such as the dog, the snake, and all the animals already mentioned to use the face of the flehmen.

The first studies date back to Jacobson, who in 1811 cited the vomeronasal organ, but was observed as early as the 1700s. In some studies it is observed that in humans the vomeronasal organ is present in the fetus but then disappears in adulthood. His disappearance in man seems to be the result of the evolution and lack of need to analyze pheromones for man, even if in later studies the presence of the Jacobson organ in the adult man was reconfirmed.

The vomeronasal organ is separated from the rest of the olfactory apparatus, and it seems that the signals it processes are not sent to the nervous system that encodes the odors, but to the areas of the brain that are more tied to the emotions. There are still many things that we do not know about pheromones and human reactions to them, certainly we should not underestimate the function they have without us realizing it.

Jacobson’s snake organ: What centers the Jacobson’s organ and the snakes? Well, they too are equipped with it, in fact the snakes use a lot of this system of analysis of the external world, extracting the tongue and thus transporting these molecules towards the mouth, to then be analyzed by the Jacobson organ of the snakes.

Jacobson dog organ: also in the dog there is the vomeronasal organ, which sends signals to the limbic system, after analyzing pheromones, to stimulate emotions, memory, and the dog’s emotional responses. Fascinating, isn’t it?

Horse vomeronasal organ: In horses the sense of smell is very important, and the use of the vomeronasal organ to analyze urine and pheromones is also important, but also substances that could be irritating to it. The horse, along with many other horses, is one of the animals that most often makes the face of the flehmen, also important in the ritual of courtship.

Cat vomeronasal organ: but let’s come to our beloved cat. In the cat, the Jacobson’s organ is placed behind the upper incisors and connected to the palate by the nasal vomero pits. Through being, the molecules are analyzed whether they come from the outside in an aerial form but also in liquid form, so that the cat perceives and analyzes the messages contained in the pheromones.

Also in the cat, the receptors of the vomeronasal organ analyze the messages and then send the signals to the limbic system, where the emotional responses of the cat are governed. For this reason pheromones are very important for the cat as a signal of familiarity with an environment or other beings or even as a signal of danger, as well as a sexual signal.

It is an invisible and mysterious language for us humans, but for the cat it is very important and vital, from which it collects a lot of information which in turn deposits through the markings, which can be facial, urinary, scratches, etc.

I hope in this article to have explained you a little better how the Jacobson organ of the cat works and to have made you know because the cat’s flehmen is a grimace not made at random, but at that moment your cat is analyzing important information . Have you ever noticed the flehmen in your cat? Tell us your experience in the comments.