Jill is a PhD student who is writing her dissertation on a population of rats. These rats are in the wild. The majority of the population consists of darkly-colored rats. After 5 years of observations, rats with white fur outnumber the dark-colored rats.

Question

Jill is a PhD student who is writing her dissertation on a population of rats. These rats are in the wild. The majority of the population consists of darkly-colored rats. After 5 years of observations, rats with white fur outnumber the dark-colored rats.

In three to five sentences, provide two or more different explanations of why Jill is seeing this change in her wild rat population. Please use vocabulary you learned in this unit.

Answer 1

One possible explanation for the change in the rat population could be natural selection. If the area where the rats live has experienced changes such as temperature or vegetation, the white fur may provide an advantage for the rats to thrive in the new environment. Another possible explanation could be genetic drift, which is a random change in the frequency of alleles in a population over time. This could result in an increase in the frequency of the white fur allele due to chance events, rather than natural selection.

Answer 2

There are several possible explanations for the change in the rat population observed by Jill. First, genetic mutation and natural selection could have favored rats with white fur over the course of five years. If the dark-colored rats were more visible to predators, they may have been selectively preyed upon, allowing the white-furred rats to survive and reproduce more successfully. Second, there could have been an influx of white-furred rats from neighboring populations, leading to an increase in their numbers. This could have been driven by migration or accidental transport of rats with white fur into the area. Finally, changes in the environment, such as increased vegetation cover or altered prey availability, could have provided better camouflage or reduced the advantage of dark fur, leading to an increase in the white-furred rat population.

Answer 3

There could be several explanations for Jill's observation of an increase in white-furred rats in her wild rat population. One possibility is natural selection, where the white fur provides a selective advantage in the environment. This could be due to changes in their predator-prey dynamics or an adaptation to new food sources that favor white rats. Another explanation could be genetic drift, where random events such as chance mating or fluctuations in birth rates influence the frequency of different fur colors in the population over time. Both natural selection and genetic drift play significant roles in shaping the genetic makeup of populations and can account for the observed changes in fur color.