What does Turbo actually want when he meows in that particularly strange way? And what kind of funny chattering noises does the normally shy, even fearful, Rocky make when he sits on the windowsill and sees a bird in the garden? Do these sounds have any meaning at all? Why do cats purr anyway, and what exactly does it mean? When and why do cats use sounds to communicate with humans? Why do we (humans and cats) seem to understand each other so well? Or is it just an illusion when we believe that we can communicate with our animals so well through speech and sounds? Is there even something like Cat-language, Feline or Cat, and if so, how similar is this “language” to our human languages?
Could it be that we might understand the sounds our cats make if we look for universal features like pitch, length, volume (acoustic sound level pressure or intensity) and melody rather than for words, grammar, vowels and consonants? In 2010, I attended a lecture about cat purring. He opened my eyes (and ears) to the fact that I, too, could apply my phonetic and linguistic knowledge, my experience and my research methodologies, to the study of cat sounds. Not just to purring, but to all cat sounds. I started eavesdropping on my own cats and other cats as soon as I returned home. I made as many recordings as I could so that I could study their phonetic characteristics.
Since then, I have been recording my own and other cats on an almost daily basis. My first big discoveries were that the frequency range in cat sounds is enormous; that cats use a very large number of different sounds in order to communicate with us humans and with their fellow felines; and that the fundamental frequency can rise very rapidly from approximately 25 hertz (number of oscillations per second, Hz) to over 1100 Hz. All of the sounds of both human and cat language (our vocalizations) are produced when a stream of air encounters an obstacle either in the larynx (voice box) or farther upward in the vocal tract. This may occur in the larynx when, for example, producing a vowel as the airstream from the lungs encounters resistance in the form of the vocal folds held closely together and thus causing them to vibrate, but also at the front part of the palate (alveolar ridge) directly behind the teeth, when we use our tongue to produce at or an s, or between the lower lip and the teeth, when we pronounce an f. That an s or an I sounds brighter than an h or an o also has to do with articulation. The size and shape of the mouth or oral cavity determine the color (or resonance) of a sound.
The organs cats use to produce sounds are smaller than ours, but they are similar. Both humans and cats have larynxes, tongues, palates, lips and jaws. Cats move them in much the same way we do when they produce their sounds. That is why we can also study the sounds of cats using phonetic methods.
