Under both the handicap principle and the good genes hypothesis, the male trait functions as:

1. Two hypotheses converge on the same interpretation of ornaments. 2. The good genes hypothesis links ornaments to metabolism and disease resistance. 3. In both the handicap principle and the good genes hypothesis, the trait is an honest signal. 4. It signals the males' quality. 5. That gives females a way to find the fittest mates. _Source: OpenStax Biology 2e (CC BY 4.0), Ch 19 'The Evolution of Populations', sections 19.1-19.3_