An earthquake drastically reduces the size of squirrel population. The surviving population happens to have broader stripes on average than the initial population. If broadness of stripes is genetically determined, what effect has the squirrel population experienced during the earthquake

A genetic bottleneck

Explanation:

A genetic bottleneck occurs as an event that drastically reduces the size of a particular population producing a decrease in the gene pool as a lot of the gene variants is taken along with it.

The bottleneck effect may be caused by various events, such as an environmental disaster, excessive hunting etc.

The genetic bottleneck occurs when a gene pool is narrowed to a fraction of its former diversity and then taking along with it a lot of genetic variants leading to the increased frequency of the broader striped population.

clumped distribution, because you'de have all of the population gathered in a relatively small are.

it's the most common because it provides protection and a mate for reproduction

example: humans, seeweed, cattles, etc.