Cat purr

[shkrobius]

...Cats purr at a frequency of 26 Hz. Purring frequency for individuals does not change with age. Purring can occur simultaneously with other vocalization. The primary mechanism for sound and vibration production is a centrally driven laryngeal modulation of respiratory flow. The diaphragm and other muscles appear to be unnecessary for purring

Comments

[stas]

Yes, it surprised me too when I learned it is not known how exactly cats purr. Makes one rethink the limits of human ignorance.
BTW my personal observations suggest purring has absolutely nothing to do with food.

[shkrobius]

The last paper is really something. They suggest that 26 Hz purr adds reverberation to a screachy "baby" cry at 300-900 Hz making it especially annoying. The precise analog would be Tarzan's call, when you beat your chest as you vocalize! You add some low-frequency amplitude modulation to a high-frequency sound. I wonder if cats themselves know why they purr. Did Tarzan know why he was making Tarzan calls?