Well, I know when both of my cats (Sam and Babe) want to eat---that's for sure. I just didn't know how much power they actually have over the human race.

If you've ever wondered who's in control, you or your cat, a new study points to the obvious. It's your cat.

Household cats exercise this control with a certain type of urgent-sounding, high-pitched meow, according to the findings.

This meow is actually a purr mixed with a high-pitched cry. While people usually think of cat purring as a sign of happiness, some cats make this purr-cry sound when they want to be fed. The study showed that humans find these mixed calls annoying and difficult to ignore.

"The embedding of a cry within a call that we normally associate with contentment is quite a subtle means of eliciting a response," said Karen McComb of the University of Sussex. "Solicitation purring is probably more acceptable to humans than overt meowing, which is likely to get cats ejected from the bedroom." They know us

Previous research has shown similarities between cat cries and human infant cries.

McComb suggests that the purr-cry may subtly take advantage of humans' sensitivity to cries they associate with nurturing offspring. Also, including the cry within the purr could make the sound "less harmonic and thus more difficult to habituate to," she said.