When a cat sniffs intently at a new bag or piece of furniture, it is engaging with its world in a way humans often overlook. For felines, scent provides a foundational layer of information, often superseding what they see or hear. Their daily experiences, from understanding their environment to communicating with others, are deeply intertwined with the subtle chemical signals around them. This powerful sense allows them to navigate, identify, and interact within their territory.
How a Cat’s Nose Works
A cat’s sense of smell stems from its anatomy. Cats possess around 200 million olfactory receptors in their noses, significantly more than humans. This increased receptor count allows them to detect a broader range of odors and at much lower concentrations. Their larger olfactory membrane, approximately four times that of humans, further enhances their ability to process scent information.
Beyond the primary olfactory system, cats also utilize a specialized structure called the vomeronasal organ, or Jacobson’s organ. This auxiliary organ, located in the roof of their mouth, connecting to the nasal cavity through small ducts. The vomeronasal organ is particularly adept at detecting non-volatile chemical compounds, such as pheromones, which are species-specific chemical signals influencing behavior or biological processes. This dual system provides cats with a comprehensive understanding of their chemical surroundings.
Understanding the Flehmen Response
A cat with curled lips and a slightly open mouth is exhibiting the Flehmen response. This behavior draws air and scent molecules into the vomeronasal organ for more detailed analysis. It channels chemical signals, particularly pheromones, directly to this specialized sensory organ.
The Flehmen response allows cats to gather nuanced information. This includes details about other cats, such as their reproductive status or territorial boundaries. Cats commonly exhibit this response when investigating urine marks from other felines, new objects in their environment, or strong, unfamiliar odors. It acts as a sophisticated chemical analysis system, blending elements of both taste and smell.
Communication Through Scent Marking
Cats use their own scent as a primary form of communication, establishing their presence and defining their territory. One common method is “bunting,” where a cat rubs its cheeks, chin, and forehead against objects, people, or other animals. These areas contain scent glands that release pheromones, marking the item or individual as familiar and safe. Bunting also serves as a bonding gesture among friendly cats, creating a shared group scent.
Scratching is another way cats leave scent messages. The pads of their paws contain scent glands that release pheromones when they scratch a surface. In addition to conditioning their claws and stretching, scratching leaves both a visual mark and a chemical signature. Cats often choose prominent objects like furniture or scratching posts to deposit these territorial signals.
Urine spraying serves as a form of scent communication, distinct from normal urination. When spraying, a cat stands, quivers its tail, and directs a small amount of urine onto a vertical surface. This behavior conveys messages about territorial ownership, sexual receptivity, and can also be a response to stress or anxiety. While more common in unneutered males, both male and female cats can engage in spraying.
Scents That Attract and Repel Cats
Certain environmental scents can elicit strong reactions from cats, influencing their behavior in various ways. Catnip, derived from the Nepeta cataria plant, is known for its euphoric effects on many felines. The active compound, nepetalactone, interacts with receptors in a cat’s nasal tissue, causing behaviors like rolling, rubbing, and increased playfulness. Silver vine (Actinidia polygama) and valerian root (Valeriana officinalis) also contain compounds that can produce similar stimulating responses in some cats, even those unaffected by catnip.
Conversely, many scents are disliked by cats due to their heightened sense of smell. Citrus fruits, including lemon and orange, release aromas that cats find overpowering and often avoid. Strong mint varieties, excluding catnip, and lavender are also unpleasant for felines. Harsh chemical cleaners, eucalyptus, and strong spices like cinnamon can also deter cats due to their intense odors. These repellent scents are sometimes used in commercial deterrents to guide cat behavior.