Teenage girls collude through song; music is a secret code, a signal, a warning. Maybe that’s why Showtime’s Yellowjackets is so good at reaching deep into my lizard brain and splattering my adolescent memories all over the screen. Like in the second episode, right after teenage Misty (played with impeccable ick by Samantha Hanratty) chops off her coach’s mangled leg, the chorus to “Mother, Mother,” Tracy Bonham’s 1996 alternative chart topper — “I’m hungry / I’m tired / I’m losing my mind / everything’s fine” — drops at full volume. This song, this goddamn perfect song. The lyrics pour over Misty’s blood-spattered face as she locks eyes with the viewer, capturing everything that’s so great about the first season of this show: It’s not just a Lord of the Flies…