Molecular Clock Hypothesis
Evolution & Adaptation
1962
Discoverers: Emile Zuckerkandl, Linus Pauling
Overview
The observation that protein and DNA sequences accumulate mutations at roughly constant rates, allowing estimation of divergence times between species.
Significance
Provided a quantitative method to date evolutionary events independent of the fossil record, transforming molecular phylogenetics.
Methodology
Comparison of haemoglobin amino acid sequences across mammalian species, correlating sequence differences with estimated divergence times.
Impact
- Enabled molecular dating of evolutionary divergences
- Complemented fossil-based timelines
- Underpinned modern phylogenomics