Final answer:
A female bird that chooses a brightly colored male often gains the benefit of mating with a partner who displays signs of higher disease resistance. This is because bright coloration can be an indicator of good health and genetic fitness, which are desirable traits that can be passed on to offspring.
Step-by-step explanation:
The question asked is concerned with the potential benefits a female bird might gain from choosing a brightly colored male as a mate. In the context of sexual selection, the bright coloration of the male is often a signal of greater fitness, which can be associated with traits such as higher disease resistance. The female birds are selective and tend to choose mates that are likely to provide the best genes for their offspring. For instance, a male bird's colorful plumage could indicate his overall health and his ability to evade predators, hence suggesting that he possesses good genes that could be passed on to offspring, including traits like disease resistance.
In the process of sexual dimorphism and selection, colorful males do not necessarily partake in parental care, as they invest energy in visual displays to attract females rather than in child-rearing. However, in some species, males that engage in elaborate courtship rituals or have colorful plumage might also assist with parental care, meaning energy is not solely dedicated to attraction and can be diverted towards nurturing offspring when needed.
Thus, a female bird that chooses a brightly colored male might gain offspring with higher disease resistance, rather than benefits such as increased predation risk, better singing ability, or camouflage protection.