molecular clock

This term describes a specialized bio-chronological tool rather than a physical timepiece. It relies on the premise that genetic mutations accumulate at a relatively constant rate over millions of years, allowing scientists to calculate the timing of evolutionary divergence.

In academic and scientific registers, it is used as a technical methodology. It is often contrasted with the fossil record, which provides physical evidence of existence, whereas the molecular clock provides a calculated estimate of time based on genomic sequences.