Molecular Clocks: Determining the Age of the Human–Chimpanzee Divergence

Abstract The approximate clocklike nature of the accumulation of nucleotide substitutions (the ‘molecular clock’) allows for the estimation of the time of divergence between modern species, dependent on calibrating the clock with known divergence dates from the fossil record. The molecular clock gives dates of approximately 6–8 million years ago for the human–chimpanzee divergence, in general agreement with the palaeontological evidence.