Arizona State University (ASU) BIO345 Evolution Exam 1 Practice

Molecular clocks are tools used by scientists to estimate the time of evolutionary divergence between species. They rely on the idea that mutations accumulate at a relatively constant rate over time in the DNA of different organisms. By comparing the genetic differences between species and calibrating these differences against known divergence times from the fossil record or other reliable sources, scientists can infer when two species last shared a common ancestor. This can provide insights into the timing of evolutionary events, helping researchers understand how long ago species diverged from one another.

This method is particularly useful because it allows for the estimation of divergence times even in cases where the fossil record is sparse or nonexistent, giving a deeper understanding of the evolutionary history of life on Earth. Additionally, molecular clocks can be adapted to different groups of organisms and types of genetic material, making them a versatile tool in evolutionary biology.