Why does a cat's jaw click when it yawns? - briefly
The clicking sound you hear when a cat yawns is due to the movement of its lower jawbone, known as the mandible. This bone has a unique structure with a notch that allows it to move freely and can produce an audible click when the cat opens or closes its mouth widely, such as during a yawn.
Why does a cat's jaw click when it yawns? - in detail
The clicking sound that occurs in a cat's jaw during yawning is a phenomenon that has intrigued both pet owners and scientists alike. This audible event, known as temporomandibular joint (TMJ) clicking, is not unique to cats but can also be observed in humans and other animals. To understand the mechanics behind this occurrence, it is essential to delve into the anatomy of a cat's jaw and the physiological processes involved during yawning.
The TMJ is a complex joint that connects the lower jaw (mandible) to the temporal bone of the skull. It is composed of several components, including the articular disc, which acts as a cushion between the mandibular condyle and the glenoid fossa. This disc facilitates smooth and silent movement of the jaw, allowing for activities such as eating, drinking, and communicating through vocalizations.
During a yawn, a cat's jaw undergoes a significant range of motion, opening wide to expose its teeth and tongue. This extensive movement can lead to temporary displacement or dislocation of the articular disc within the TMJ. As the mandible returns to its resting position, the disc may snap back into place, producing the characteristic clicking sound. In some cases, the clicking noise might also be accompanied by a slight popping sensation, which is often imperceptible to the cat but noticeable to humans.
It is important to note that TMJ clicking in cats is generally considered a normal and benign occurrence. However, if the clicking is accompanied by signs of discomfort or pain, such as reluctance to eat, excessive drooling, or difficulty opening and closing the mouth, it may indicate an underlying issue with the TMJ. In such cases, consultation with a veterinarian is recommended to rule out potential problems like dental disease, fractures, or arthritis of the temporomandibular joint.
In conclusion, the clicking sound in a cat's jaw during yawning is primarily attributed to the temporary displacement and subsequent realignment of the articular disc within the TMJ. This mechanism allows for the extensive range of motion required for a deep yawn while ensuring the smooth functioning of the joint. While this phenomenon is typically harmless, pet owners should be vigilant for any signs of discomfort or pain that may warrant veterinary attention.