The urchin in cats is located in the throat - these are the vocal cords and the muscles of the larynx, which quickly contract and relax during breathing, which produces a sound called rumbling. Until recently, everyone thought that only domestic cats and some of their small wild cousins, which belong to the feline family, have a urchal, while large ones such as lions or tigers are not capable of rumbling in principle. This opinion was based on the fact that the hyoid bone, which is involved in the process of sound production, in large felines contains cartilaginous tissue, which allows them to emit a very loud roar, even a roar, while in other cats this bone is completely calcified and is hard design.
Recent studies have shown that large cats can also purr, but not all. For example, tigers, lions, jaguars, and leopards can purr, but only when they exhale, while snow leopards can turn on the urchin both when inhaling and when they leave.
Fun fact: most cats stop purring when they hear the sound of running water. The trick is used by veterinarians when you need to listen to a cat, and he hums. It is almost impossible to hear a heartbeat or breathing while the urine is running, so you have to turn on the tap.
Cats produce sounds just like us, by passing air from their lungs through two fibrous, elastic vocal cords located in the larynx. However, unlike humans, a cat does not use the tip of its tongue to shape these sounds, but instead creates thirteen distinct vowels by altering muscle tension in the mouth, throat, lips, and nasal sinuses. The cat also emits from seven to eight consonants - it does this by opening and closing its mouth, changing its shape, and, in a variety of ways, in order to change the resonance.
Purring occurs due to vibrations rhythmically occurring in the larynx of the animal. It is interesting that regardless of breed, gender, age, the frequency of oscillations is the same - 25 cycles per minute.
By the way, with the help of purring cats are able to heal themselves and other cats, as well as people. You probably felt it on yourself if you have a cat. Agree, when this animal comfortably nestles next to the place that hurts, and begins to rumble, then the pain subsides, and the soul becomes calmer and more joyful. And it doesn't matter what your beloved cat is purring with. What matters is that he just hums.