- The molecular clock is used to estimate the time when two forms of life diverged from each other. It is based on the observation that evolutionary changes in the sequence of an RNA or a protein molecule occur at a fairly constant rate.
- The difference in the amino acids of, say the haemoglobin of two animals can tell you how long ago their lineages diverged.
- The molecular clock is useful for obtaining evolutionary information when there is little or no fossil record.
- Molecular clocks corroborate well with other evidence, such as the fossil record.
- Scientists across a range of biological disciplines use a technique called the molecular clock, where the past is deciphered by reading the stories written in the genes of living organisms.
- On the largest scale, the molecular clock has enabled palaeontologists to unveil the story of evolution over millions of years.
- And on the smallest scale, epidemiologists are able to trace the spread of disease over mere decades. The molecular clock has provided a narrative for evolution across short and long timescales.
- In 2012, researchers concluded that the AIDS epidemic in India had a common ancestor 40 years ago, and from this they could infer the spread of the disease.
- The molecular clock can also be used for putting a series of evolutionary events into chronological order. This is done by comparing sequences from different species to determine when they last shared a common ancestor, in effect drawing the family tree.
