When two lineages split from a common ancestor, each accumulates different mutations over long periods of time. The number of mutations is proportional to
the length of time that the two groups have been genetically separate.
A scientist studies corresponding genes in two species. Which data would be
most useful for determining the time when the split from the common ancestor
occurred?
a. mutation rate and the number of mutations in each sequence
b. mutation rate and the number of nucleotides in each sequence
c. mutation rate and the number of nucleotides that differ between the two
sequences
d. the number of repeated nucleotides and their specific locations in the two
sequences