Song Sparrow  says, "Nobody loud talks Little Seymour"

Researchers at Cornell's Lab of Ornithology have come up with a new way to study how birds communicate — recording their songs and then playing them back to other birds of the same species. They use the recordings to decipher strategies that various species use to attract mates and resolve territorial disputes.

Song sparrows in southern California live up to their reputation as tough hombres when they hear the recordings. These gang bangers interpret some songs as "fighting words" and sing the same type of song — known as song-type matching, or snaps — back to one another. These bad dudes come right up to the speaker and throw down.