The first bit of screechy call works like an identifier, providing information about the animal making the racket. This is important for mongoose relationships, because the animals can recognize individuals based on this sound. The second, more tonal part of the call indicates what the animal is doing. Study coauthor David Jansen compared that second part to a vowel, and says it shows for the first time that mongoose, at least, make sounds in a way that bears some resemblance to the way we build words. The study appears in BMC Biology.