animal care |

animal care : "The Physiology of Purring
There seems to be two schools of thought here.
The most popular one is quoted here:
One study determined that purring involves activation of nerves within the voice box. These nerve signals cause vibration of the vocal cords while the diaphragm serves as a piston pump, pushing air in and out of the vibrating cords, thus creating a musical hum. Veterinarian Neils C. Pederson, author of Feline Husbandry, believes that purring is initiated from within the central nervous system and is a voluntary act. In other words, cats purr only when they want to.²
The other theory is that the sound comes more from vibrating blood vessels than in the voicebox itself. "