The Bird Way: A New Look at How Birds Talk, Work, Play, Parent, and Think

by Jennifer Ackerman

brown-headed cowbird mothers use a special “chatter call” that gives nestlings a key bit of information: self-knowledge. “The female brown-headed cowbirds produce the chatter call in different social contexts,” says Louder. “The call acts as an acoustic password cue for her offspring, guiding their choices about who they learn from, so they learn the songs of their species and identify appropriate mates.” Hearing the password actually changes the brains of the young birds, transforming the auditory region of the brain into a state ready for learning the songs of their own kind. In this way, a mother cowbird tells young cowbirds who they are and what they should become—a brood parasite rather than a member of their host species.