Question

NEED HELP QUICK ON BIO FINAL

The graph below shows the frequency of moths in a population. The original population had more black and white speckled moths, but the new population has more dark-colored moths.


a. What type of selective pressure was taking place in this population?

b. Come up with a hypothesis related to genetic drift or sexual selection about why this shift may have occurred in the population.

Answer 1

This actually happened in real life. A hypothesis for b. is that if pollution made the trees in the moths environment darker, then the dark moth population would increase because they blend in with the darker trees better than the speckled moths and are not as visible to predators (this is related to genetic drift). Therefore a. would be natural selection since the dark moths are more fit to the environment.