Question

1. What is often true about the relative rates of phenotypic evolution of sexually selected traits vs most other kinds of traits?

2. In the good genes model, why does a male trait have to be costly in order for the female preference to be maintained by natural selection?

3. Explain the Fisherian (runaway)model of sexual selection –what generates correlations between female preferences and male traits. What kind of experimental observation would support the model?

4. Explain the concept of sensory/sexual exploitation. Provide a real possible biological example.

5. Give one example where there are fitness conflicts of interest between the sexes resulting from a sexually selected trait?

Answer 1

Ans 1: The sexually selected traits are often evolving more quickly as compared to other traits

Ans 2: Good gene models are costly because of the

Females prefer males who possess "good genes". the genes that code for favorable traits

They enhancing the fitnesses of offspring

The elaborate trains are costly to produce and maintain

Ans 3: This model claims the positive associations made up between desire and traits cause to a positive feedback loop resulting in the evolution of better traits and desires even if the male traits are not associated with overall higher quality genotypes.

This model shows that preferred males do not sire overall higher quality offspring, but do sire sons that also tend to be preferred by females

Ans 4: This is the idea that pre-existing sensory bias of females can lead to the higher mating success of males that have traits that are favored simply because of the female sensory bias

The real possible biological example male call of tungara frogs and the tails of swordtail fishes

Ans 5: The example for the fitness conflicts of interest between the sexes resulting from a sexually selected trait is Flies, The male-male competition in the form of sperm competition may have led to the evolution of ejaculate products that may be harmful to the female