Scientists have cracked the mystery of how cats produce the purring sound that signals their approval. It turns out they use a strikingly similar technique to “vocal fry” – the croaky voice used by the singer Katy Perry and reality television star Kim Kardashian.
Researchers have long puzzled over how an animal as small as a domestic cat can produce the deep resonance of a purr, when such vocalisations are usually only produced by animals with far longer vocal cords, such as elephants. For many years, they believed purrs were produced using a unique mechanism that involved the cyclical contraction and relaxation of muscles in the voice box – something that would require constant neural input from the brain.
