Imagine that you are studying a species of guppy in which mature males are obser
ID: 255233 • Letter: I
Question
Imagine that you are studying a species of guppy in which mature males are observed to have bright orange tails, while females and immature fish have grey tails. You decide to test whether sexual selection can explain this dimorphism. Describe an experiment to test this hypothesis. Include details about what you will measure. Draw and label two diagrams: one showing potential data that would refute your hypothesis, the other showing potential data that would support it. A competing colleague discovers that some mature males in this population have grey tails, and publishes a paper claiming that this evidence shows that sexual selection could not explain the dimorphism in tail color in this species. Do you agree or disagree? What observations or experiments could help you refute your colleague’s conclusion
Explanation / Answer
Guppy females select males depending on their color cues . This method of selecting males for mating is called as sexual selection. This type of selection takes place when there is more number of males in a particular habitat to compete with a female. Females get confused in choosinhg males for copulation. The above point can be tested using UV transmitting filters. Guppies have the ability to absorb UV rays and gets brightly colored. So , inorder to test this 2 male guppies with bright colored and dull colored are allowed inside an aquarium containing a female guppy . Under UV spectra , males with bright spots perceive UV light and gets bright compared to dull colored male. Female guppy will prefer male which is brightly colored. Colleague's experiment is false . Some males are grey colored and this character is used by other males which is brightly colored to exploit themselves. Similarly as above experiment using UV transmission, Bright orange colored and grey colored males are allowed into an aquarium containing female and allowed for mating. Female guppies prefer orange male guppies compared to male guppy that is grey.