The Grand Canyon was carved out by the Colorado River several million years ago. This caused the separation of members of one squirrel species. The Abert’s Squirrel lives on the southern side of the canyon and in other parts of the United States. A second species, the Kaibab Squirrel, has been found around the northern rim of the canyon and nowhere else in the country. According to the process of natural selection, we know that there must have been some genetic variation among the existing squirrel population, but how did that lead to the development of a second species?

B-

Explanation:

There were both genetic variations and environmental variations. In each location, the genetic variations helped certain squirrels survive to reproduce. Those unique and differing traits were passed on. When the squirrels were separated, there was genetic variation within the population. In each group, some had traits that allowed them to survive and reproduce in their specific environment. Over time, each group evolved unique traits for their home location until one species evolved into two. (From usatestprep)

not the best question format lol but what i think might as scale color is controlled by a single gene with two alleles, the green allele and the yellow allele. when moths that are homozygous for green scales are mated with moths that are homozygous for yellow scales, 100% of the offspring have green scales.

c.) polymerase chain reaction

- "unlike the original dna fingerprinting method, dna profiling does not use restriction enzymes to cut the dna. instead it uses the polymerase chain reaction (pcr)? to produce many copies of specific str sequences. pcr is an automated procedure that generates lots of copies of a specific sequence of dna."