the display of sensory preferences that may not relate to species-typical signals. Female tungara frogs prefer a low-pitched chuck note that males add to courtship calls, and females of a closely related species also prefer low-pitched chuck notes, even though males of their species do not produce these notes. The preference for low-pitched chuck notes is a sensory bias that can be exploited by any males able to add such a note to their mating calls. See sensory exploitation.