Darwin recognized that characteristics that make animals a target for predators also reduce survivability and reproduction, Able noted. Darwin's rationale, that conspicuous male displays persist and grow ever more conspicuous because mating females prefer them, never fully explained the benefit of choosing the brightest or loudest. However, in the last 15 years, evolutionary biologists began to focus on debilitating parasite infections and inherited resistance to infection.
Experiments show that the brightest jungle fowl males have the greatest mating success.
In his analysis, Able examined previous studies of parasite transmittability in 15 species with conspicuous male displays. When the analysis was complete, six of eight species with associatively transmittable parasites showed a negative correlation between parasite intensity and male mating success. In other words, males with the fewest transmittable parasites have the most conspicuous traits and the best luck. But it is beginning to look like, when a female selects a flamboyant male, avoiding contagion may be more important than getting good genes. A graduate of Indiana University with a degree in biology, Able has been conducting his research and teaching at Cornell for seven years with teaching assistantships in introductory biology, animal behavior and animal social behavior.