The following questions refer to the paragraph and graphs below.
In a hypothetical situation, the National Park Service, which administers Grand Canyon National Park in Arizona, builds a footbridge over the Colorado River at the bottom of the canyon. The footbridge permits interspersal of two closely related antelope squirrels. Previously, one type of squirrel had been restricted to the terrain south of the river, and the other type had been restricted to terrain on the north side of the river. Immediately before and ten years after the bridge's completion, ten antelope squirrels from both sides of the river were collected, blood samples were taken, and frequencies of alleles unique to the two types of antelope squirrels were determined (see graphs below).

-In order for speciation to occur, what is True?
A)The number of chromosomes in the genome must change.
B)Changes to centromere location or chromosome size must occur within the genome.
C)Large numbers of genes that affect a single phenotypic trait must change.
D)Large numbers of genes that affect numerous phenotypic traits must change.
E)At least one gene, affecting at least one phenotypic trait, must change.

Question

The following questions refer to the paragraph and graphs below.
In a hypothetical situation, the National Park Service, which administers Grand Canyon National Park in Arizona, builds a footbridge over the Colorado River at the bottom of the canyon. The footbridge permits interspersal of two closely related antelope squirrels. Previously, one type of squirrel had been restricted to the terrain south of the river, and the other type had been restricted to terrain on the north side of the river. Immediately before and ten years after the bridge's completion, ten antelope squirrels from both sides of the river were collected, blood samples were taken, and frequencies of alleles unique to the two types of antelope squirrels were determined (see graphs below).

-In order for speciation to occur, what is True?
A)The number of chromosomes in the genome must change. 
B)Changes to centromere location or chromosome size must occur within the genome. 
C)Large numbers of genes that affect a single phenotypic trait must change. 
D)Large numbers of genes that affect numerous phenotypic traits must change. 
E)At least one gene, affecting at least one phenotypic trait, must change.

Quizplus · Accepted Answer

Speciation can occur when at least one gene, affecting at least one phenotypic trait, changes. This can lead to genetic divergence between populations, ultimately resulting in the formation of two separate species. The footbridge in this hypothetical scenario allows for interspersal of the two closely related antelope squirrel populations, potentially leading to gene flow and reduced genetic divergence.

The Following Questions Refer to the Paragraph and Graphs Below