Question

Species A: ATTCGGATTATTCGAGG Species B: GTCCGGTTCATTGGACA Species C: ATCCAGATCGTTCGTGG Which of the following inferences can be made, based on this information?
A. Species B and Species C most likely diverged from Species A since they both have more mutations than Species A.
B. Species B most likely evolved from Species C since they are closest to each other in terms of number of mutations.
C. Species A and Species C most likely share the most recent common ancestor since they differ by the fewest mutations.
D. Species C most likely diverged from Species A more recently than Species B since Species C has fewer mutations than Species B.

Answer 1

Answer: D. Species C most likely diverged from Species A more recently than Species B since Species C has fewer mutations than Species B.

Explanation: The mutations between species A, B and C can be found counting the differences in the nucleotides (letters). So, the mutations in the sequences between Species A and Species B are 8, between Species A and C are 5 mutations and between Species B and C are 9 mutations. Then, we can proposed that species A and C are more close related because the sequences have fewer mutations and this could happen because they diverged more recently, compared to Species B that have more mutations.