But it turns out that it's not the comforting sound of the purr that heals, so much as the gentle vibration. Think of a purring cat as an ultrasound treatment on four feet.
Chickens, gorillas, ring-tailed lemurs, rabbits, raccoons, guinea pigs, squirrels and elephants also purr. But you probably wouldn't want to snuggle up to an elephant or gorilla when you need pain relief. That's where cats come in.