Final answer:
The peacock's tail is an example of the handicap principle, where a healthy, beautiful tail discourages predation and increases survival and reproduction for those individuals.
Step-by-step explanation:
In both the handicap principle and the good genes hypothesis, the trait is an honest signal of the males' quality, thus giving females a way to find the fittest mates—males—that will pass the best genes to their offspring. The peacock's tail is an example of the handicap principle. Having a healthy, beautiful tail discourages predation, helping in survival. This means that those individuals are most likely to survive and produce offspring. The speculation is that large tails carry risk, and only the best males survive that risk : the bigger the tail, the more fit the male. This idea is known as the handicap principle. An example of a trait that may have evolved as a result of the handicap principle is the large and extravagant tail of the peacock.
The idea behind the handicap principle is that only the fittest individuals can afford costly traits. In the case of peacocks, the large tail makes males more visible to predators and less able to escape, implying that it is a disadvantage for survival. However, these elaborate tails serve as an honest signal of the males' quality, thus giving females a way to choose the fittest mates—those that are most likely to survive despite the handicap and pass the best genes to their offspring. This phenomenon is a part of selection, where even detrimental traits can become sexually attractive and therefore selected for if they indicate genetic fitness.