Plenty of cat owners joke about being at the beck and call of a demanding feline, and now researchers have identified one vocal tactic that house cats use to manipulate their owners. The newly identified vocalization, called “solicitation purring,” has never been acknowledged or studied before, although cat fanciers, such as the study’s lead author Karen McComb, are quite familiar with it. “In the case of my cat, if he sees you stirring from sleep at all in the early morning he will immediately switch into giving this solicitation purring and position himself next to your head so you get the full impact” [Discovery News], she says.
Unlike the low-pitched purr that cats produce when they’re lazily lounging, this sound incorporates a high-pitched “cry” with a similar frequency to a human baby’s. The team said cats have “tapped into” a human bias – producing a sound that humans find very difficult to ignore [BBC News]. McComb suggests that cats may learn to embed the subtle wake-up call within the purring sound usually associated with contentment because more overt meowing is likely to get them kicked out of bed.
McComb points out that the solicitation purring is only possible because of a quirk of feline anatomy. Most animals make throat-based sounds using only their vocal folds. But cats can vibrate the muscles underneath their vocal folds very slowly, which produces the rumbling purr. But that action leaves the inner edges of the vocal folds free to do something else. By vibrating those inner edges while also purring, a cat can produce the higher-pitched distress call [National Geographic].
For the study, published in Current Biology, the research team had 10 cat owners record their cats’ purrs at different times, when the cats were hungry and when they were relaxing. They played back the recordings to 50 people, many of whom did not have cats, and asked them to rate how urgent and how pleasant each call was. The more pronounced the high-pitched cry was, the more urgent the call was judged to be. And in households all over the world, the solicitation purr has proved itself an effective strategy, says McComb: “If you ask people who own cats what they do when they get up they say they feed their cats. Even before they have a cup of coffee. Cats are very good at getting their own way” [The Guardian].
Image: flickr / schmollmolch