molecular clocks

A molecular clock is a method scientists use to estimate how long ago two species shared a common ancestor. It’s based on the idea that genetic mutations, or changes in DNA, happen at roughly consistent rates over time. By comparing the DNA sequences of different species, scientists can count the number of genetic differences and, knowing the approximate rate of mutation, estimate when they diverged. Molecular clocks are valuable tools in studying evolution, helping to date events in the history of life on Earth.