A molecule that can be used as a molecular clock has a neutral mutation rate of one mutation per 10 million years. How many years ago did two species share a common ancestor if the molecules found in these two species differ by a total of six mutations?

A. 6 million years

B. 10 million years

C. 30 million years

D. 60 million years

Answer;

D. 60 million years

Explanation;

The two species shared a common ancestor 60 million years ago, if the molecules found in these two species differ by a total of six mutations.

Mutation is a sudden, random spontaneous change that occur in the genetic make up of an organism or a cell.

If one mutation occurred after 10 million years;

Then six mutations will need (6 * 10) 60 million years.