vocalization

"The invitation takes the form of a 'let’s go' rumble, the same vocalizations that dominant females use to coordinate the departure of a large family," O'Connell-Rodwell said.

Many pedagogical and scientific sources suggest that the highest pitches reached in classical singing can only be produced with a so-called "whistle" voice register, in analogy to ultrasonic vocalizations of mice and rats.

“Our results show that the sounds and patterns derived from human speech can serve as a foundation for analyzing and understanding the acoustic patterns of other sounds, such as animal vocalizations.”

The same models can also glean other information from animal vocalizations, such as the animal's age, breed and sex.

The study further validates the idea that some birds use the number of vocalizations to convey ecological information, such as the presence of predators and amount of food.