Question

In an experiment with birds, researchers glued artificially longer tails to males birds that have fairly large tails to beging with and left another group unmanipulated. They then allowed males to court females and found that the males with the artificial tails were more successful at attracting mates than the normal males. This observation seems most relevant to?

1) the good genes hypothesis
2) the sensory bias hypothesis
3) direct benefits
4) intrasexual selection

Answer 1

The experiment with birds with artificially longer tails supports the good genes hypothesis (option 1) , suggesting that traits like longer tails are an honest signal of genetic fitness, leading to greater reproductive success despite potential survival costs.

Step-by-step explanation:

The observation that male birds with artificially longer tails were more successful at attracting mates than the normal males is most relevant to the good genes hypothesis. In the context of sexual selection, this hypothesis suggests that certain traits, such as longer tails in birds, act as an honest signal of an individual's genetic fitness.

Therefore, females may prefer males with these traits because they indicate good genes that can be passed on to offspring, potentially leading to fitter and healthier progeny. The experiment highlights how sexual selection favors traits that may not necessarily enhance individual survival but can increase reproductive success through attracting mates.

While other options like sensory bias, direct benefits, and intrasexual selection are aspects of sexual selection, they do not directly explain the preference for longer tails as an indicator of genetic quality. The handicap principle further supports the good genes hypothesis by suggesting that only the fittest males can afford to survive with such costly traits.