Question

A population of western skinks, a type of lizard, lives in a grassland habitat along the base of a mountain range. The construction of a multi-lane highway will divide the habitat into two separate regions. How will the construction of the highway most likely affect the western skink population?
A. The western skink population size would decrease by half, reducing the probability that the population will evolve and speciate.

B. Western skinks would become an invasive species in one of the two regions, so the total population size would increase.

C. Western skinks would become better able to find unrelated mates, decreasing the population's susceptibility to diseases.

D. The western skink population would be separated into two groups, and genetic diversity would decline in each group.

Answer 1

Answer:

Option D

Explanation:

This case of western skink is an example of geographical isolation which reduces the gene pool and hence the genetic diversity.

The entire population of western skink gets divided into two sub population. Now these two sub-populations start living in two different geographic entities due to which they evolve differently and after a long course of period if  species from these two sub population are brought closer for mating then there shall be no mating due to variation in mating preferences.

Hence, option D is correct

Answer 2

Answer:

The most appropriate answer would be D. The western skink population would be separated into two groups, and genetic diversity would decline in each group.

It can be explained with the help of a bottleneck effect due to which population size decreases suddenly due to events like a natural disaster, habitat destruction et cetera.

The construction of the multi-lane highway would have destroyed the natural habitat of western skinks and separate them into two populations.

The separation of a population along with the destruction of habitat would result in a severe decrease in the population size of western skinks.

Consequently, the genetic diversity would also decrease.