Have you ever caught your cat making a funny sneering face, with their mouth slightly open and upper lip curled? It might look like a mix of disgust and deep thought, but this is actually a Flehmen response, which is a natural behavior that helps cats analyze pheromones in their environment.
In this article, we'll explore what the Flehmen response is, why cats do it and whether you need to take any action when you see your feline making this curious expression.
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Content:
- Why Do Cats Do the Flehmen Response
- What Is the Flehmen Response
- What to Do About the Cat Flehmen Response
- Final Thoughts
Why Do Cats Do the Flehmen Response
Cats use the Flehmen response to detect pheromones in a variety of situations, such as:
- Recognizing territory (cats may respond to another cat’s scent markings or urine).
- Determining reproductive status (male cats often use Flehmen to sense if a female is in heat).
- Identifying familiar scents (such as distinguishing littermates or detecting changes in the household).
- Reacting to strong odors (catnip, new furniture, or even human sweat can trigger it!).
Dr. Benjamin Hart, a veterinary expert, explains: “Cats generally make nasooral contact with the stimulus source before performing Flehmen. This observation is consistent with the notion that Flehmen is involved in the transport of fluid-borne stimuli from the oral cavity to the VNO.”
In other words, before a cat performs the Flehmen response, they typically touch their nose or mouth to the source of the scent. This helps them collect the odor particles on their tongue, which they then transfer to the vomeronasal organ to analyze important chemical signals.
Male cats display Flehmen a lot more than females, especially when they smell urine marks left by other cats. But many scents can trigger this response, including catnip. This is probably because experts believe the scent of catnip, particularly from a compound nepetalactone, smells just like certain feline pheromones.
Want to keep an eye on your cat’s funny Flehmen moments? Check out the Petcube Cam to capture and monitor your pet's behavior in real-time.
What Is the Flehmen Response
The Flehmen response is a special way that cats gather information about their surroundings, specifically detecting pheromones (chemical signals used for communication). Many cat parents also call it the “stinky face”.
This is like "sixth sense" for social secrets because this organ helps cats detect emotional states, dominance and stress cues from other animals. They get all of this in the chemicals they pick up from the air. Male cats are most prone to it because it’s helps them tell when a female cat is ready to mate.
When a cat sniffs something intriguing, they may curl their upper lip and open their mouth slightly. This allows scent molecules to reach a special sensory organ called the vomeronasal organ (VNO) or Jacobson’s organ, which is located on the roof of their mouth.
As one Redditor writes: “My cats typically do this after the other cat has recently sat down somewhere, so, um, it's them kind of smelling the scents left behind by areas that cats will typically sit upon.”
A fun fact is that the name “Flehmen” actually comes from the German word for “lip curl,” which perfectly describes the reaction!
Quite a number of animals, such as dogs and horses, also have a VNO. Snakes have it, too, they just use their tongues to “taste” the air. Even humans have a vomeronasal organ, but sady ours is non-functional and we can’t use it like cats do.
What does the Flehmen Response Look Like?
You can tell when your can is giving the Flehmen response when they give the following behaviors:
- Sniffing an object or surface (such as urine, bedding, another cat, or even human skin).
- Licking their nose to help collect scent particles.
- Curling their upper lip and slightly opening their mouth while appearing “frozen” for a few seconds.
- A dazed or thoughtful expression, often with their head slightly tilted.
What to Do About the Cat Flehmen Response
If your cat is making that classic sneering face, there’s no need to panic! Pet parents sometimes mistake this expression for aggression, panting or even nausea, but it’s completely harmless. It simply means your cat is gathering information from their environment.
However, here are a few things to keep in mind:
Check what they’re sniffing
If your cat is reacting to another cat’s urine or scent marks, it could be a sign of territorial behavior. If it’s happening indoors, you could clean the area with an enzymatic cleaner to reduce stress if they’re worried about the pheromones left by other cats.
Let them finish
It may look funny, but try not to interrupt them! Flehmening is part of how cats analyze scents, and stopping them mid-process could disrupt what they’re trying to learn.
Pay attention to frequency
If your cat is constantly flehmening, especially in response to human sweat or unexpected objects, it might be worth asking your vet if there’s an underlying issue, such as anxiety or a medical issue.
If you’re worried, remember that the Petcube Cam lets you watch, record, and understand any odd behaviors while you’re gone.
Final Thoughts
If you ever catch your cat in the middle of this goofy, open-mouthed expression, don’t worry! It’s just their super-cool and funny way of decoding the world around them!
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