A certain segment of DNA can be used as a molecular clock. Its rate of mutation is one mutation per 15 million years. Examine the DNA segments from two different species: Species A: GTTGAGCTAGTATGGACC Species B: GATAAGCTAGTAAGGTCA Using this example, explain how this information can be used to determine how long ago these two species shared a common ancestor. Be sure to answer this question in paragraph form using complete sentences.
We can use these two DNA segments to roughly estimate how many years ago the species shared a common ancestor. First, we can count the number of differences separating segment a from segment b. Because Species B has 5 differences when compared to Species A, we see that as 5 different mutations that happened, or errors when copying the DNA. If there was one mutations per 15 million years, this means these two species shared a common ancestor around 75 million years ago. Hope I helped!
