good morning CoSo bird lovers. secret passwords keep families together.
"Superb Fairy-wrens teach their embryonic chicks a secret code. This "incubation call" contains a special note that will later serve as a password. When the chicks have hatched, this password enables the adult birds to identify their babies in the darkness of their domed nest. wren chicks learn their mother’s song and incorporate the password note into their begging calls."
https://www.birdnote.org/listen/shows/fairy-wrens-sing-secret-passwords-unborn-chicks