Have you ever observed your cat with his mouth partially open and upper lip pulled back in what appears to be a sneer or a look of disgust? Typically this will be accompanied by a look of intense concentration. This behavior is called the “Flehmen response” and can also be seen in other animals.
Your cat has something called a Jacobson’s organ, or vomeronasal organ, located in the roof of the mouth behind the front teeth. When your cat makes this strange face, it is because he has smelled something interesting and is drawing the scent into the Jacobson’s organ to get a better smell. The tongue traps the scent and transfers it to the vomeronasal organ in the roof of the mouth for better analysis.
Along with your cat’s highly-attuned sense of smell, the Jacobson’s organ provides additional sensory information and is especially attuned to detecting cat pheromones. So while it might look like your cat is disgusted when exhibiting the Flehmen response, your cat is actually enjoying a particularly interesting scent.
Have you ever seen your cat exhibiting the Flehmen response?