Question

In a city park, it is noticed that within a population of brown squirrels there are some white or albino phenotypes.  The city council decides that this would be a terrific tourist attraction and passes a law forbidding anyone to hunt, capture, move, or kill any of the albino forms of the normally brown squirrels.  Brown coat color indicates the ability to produce the pigment melanin, which is a product of a dominant allele, B.  The albino coat color or absence of melanin production is under the control of the recessive allele, b.

A world famous population geneticist, Dr. Otto Meckanick, decides to study this population of squirrels to determine whether gene frequencies for coat color change with time.  In 1998, he takes a random sample of the squirrel population.  This sample contains 4 albino and 36 brown squirrels. In 2018, he takes a second random sample of the population and finds 32 albino and 43 brown squirrels.  

A) Calculate the gene frequencies for each sampling period.  (Show work!)

B) Is either allele undergoing positive selection over time?  If so, which one?

C) Where did the allele for albinism most likely come from?  How might it have entered this population of previously brown to gray only squirrels?

D) Would you expect to see similar results in wild natural population?  Explain.

Answer 1