A penguin with an unconventional call inspires researchers to change how they study penguins

An emperor penguin's sex determines the nature of their courtship call—male vocalizations are composed of long, slow bursts with lower frequency tones than the female version. But calls of SeaWorld San Diego male penguin E-79 caught the attention of researchers by defying this binary. Also unusual was this penguin's male companion, E-81. The pair "kept company" and sometimes exhibited ritual courtship displays.