Mate value is perceived through signals and cues. Signals are characteristics that have been selected for because they offer reliable changes in receiver behavior that lead to higher reproductive success for the receiver. Conversely, cues have not been selected for to carry meaning, instead they are byproducts. However, with sexual selection, cues can become signals over time. Costly signals are ones that require intense effort for the signaler to send. Because they require high investment, costly signals are typically honest signals of underlying genetic qualities. However, signals that are not costly enough can be faked and therefore are not associated with the underlying benefits.
