When considering large predatory cats, the powerful roar often comes to mind. However, not all large felines possess this iconic ability. The cheetah, known for its incredible speed and distinctive spotted coat, is a notable exception among its larger counterparts. It communicates through a diverse range of sounds that do not include a roar, a unique vocal characteristic rooted in specific biological differences.
The Cheetah’s Unique Vocal Repertoire
Cheetahs employ a varied array of sounds to communicate, contrasting with the roaring ability of other big cats. They frequently purr, much like domestic cats, often indicating contentment or serving as a self-soothing mechanism. Cheetahs also use chirps, particularly between mothers and their cubs, to locate each other and signal distress or safety.
Beyond these, cheetahs produce growls and hisses during encounters or as warnings. They can also emit meows, similar to house cats, to express emotions. Other specialized vocalizations include an “explosive yelp,” chirrs used in courting, and howls employed by adults searching for lost family members.
The Anatomy of a Non-Roar
The fundamental reason cheetahs cannot roar lies in the unique structure of their hyoid bone, a U-shaped bone in the throat that supports the tongue and larynx. In roaring felines, such as lions and tigers, this bone is not fully ossified; instead, it consists of an elastic ligament. This flexible connection allows the larynx and vocal cords to stretch significantly, creating a larger sound-producing passage necessary for deep, resonant roars.
Conversely, cheetahs, along with smaller cats like domestic felines, possess a fully ossified, rigid hyoid bone. This fixed anatomical arrangement restricts the extensive movement of the larynx and vocal cords required for roaring. While this structure prevents roaring, it enables continuous purring, as their vocal cords are divided and vibrate during both inhalation and exhalation. Their vocal folds are sharp-edged and more suited for vibrating rapidly to produce purrs and other high-pitched sounds. This anatomical distinction highlights a key evolutionary divergence in feline vocal capabilities.
Categorizing the Big Cats
The ability to roar or purr has been a significant factor in classifying members of the cat family, Felidae. Cats that can roar belong primarily to the genus Panthera, including lions, tigers, jaguars, and leopards. These species share the flexible hyoid bone structure that facilitates their powerful vocalizations.
Cheetahs, classified in their own genus Acinonyx, are grouped with the “purring cats” or the Felinae subfamily. Despite their large size, cheetahs’ vocal anatomy aligns more closely with domestic cats and cougars, enabling them to purr but not roar. This means that, from a physiological standpoint, cheetahs are considered large members of the “small cat” group. An interesting exception is the snow leopard, a Panthera genus member, which possesses the flexible hyoid bone but cannot roar due to other vocal cord differences.