Copy of Friday (02/13) - Mechanisms of Evolution AAC (5/2/2026)

When a whale moves from one pod to another and successfully mates, it introduces new alleles into the new pod's gene pool. Over time, this exchange of genetic material makes the gene pools of both pods more similar and increases genetic diversity in the population.

Which mechanism of evolution is responsible for this change in genetic diversity?

The mechanism responsible is for this change in genetic diversity because .

A small population of mice with brown fur and white fur live in a field. One day, a wildfire, drastically reduces the population size, leaving only a few mice behind.

Over the next few generations, the gene pool of the mouse population shifts, and brown fur becomes much more common in the population, despite there being no advantage to having brown fur in that environment.

What mechanism of evolution is responsible for the change in fur color in this scenario?

The mechanism of evolution responsible for the change in fur color is .

As a result of this change the populations

.

A group of 10 giraffes from a larger population becomes isolated in a new, remote valley after a natural disaster. The valley has different environmental conditions than the original habitat, and only these 10 giraffes are able to establish a new population. Over time, the new giraffe population grows to 200 individuals, but it displays a reduced genetic diversity compared to the original population.

What type of change is responsible for the reduced genetic diversity in the new giraffe population, and how did this phenomenon occur?

is responsible for the in genetic diversity in the new giraffe population, .

Beavers build a dam over a previously un-passable river. This allows deer from one side of the river to mate with deer from the population on the other side of the river, changing the allele frequency in both populations.

The beavers indirectly influenced the evolutionary direction of the deer populations by facilitating. This demonstrates how ecological changes caused a(n) in genetic diversity.

Geneticists have determined that majority of individuals in an isolated island population have blood type B. Type A blood is found to be more common in the mainland population from which the island was settled.

The type of mechanism is because

In a grassland ecosystem, a population of gazelles has a range of running speeds. Some gazelles are naturally faster, while others are slower. Cheetahs, the main predators of the gazelles, hunt by chasing down their prey. Over many generations, researchers observed their average running speed shown in the graph below.

Based on the graph data the running speed of the gazelles through generations. This is due to because.

A group of 12 wildflowers from a larger meadow population is accidentally transported to a new, isolated valley by a passing river. The flowers are able to grow and establish a new population in this valley, where they are sheltered from the original meadow population.

Based on the data shown on the graph above Complete the following statement a researcher can conclude.

Over several generations, researchers notice that the flowers in the valley show an in the isolated valley, while the original population predominantly has .

The cause for this event is due to the since .