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The scientific history of reconciling the considerable body of paleontological knowledge of past species, with genomic data obtained from today's species has been an often fractious one, with one or the other form of data presumed superior, depending on the practitioner.  Zuckerkandel and Pauling first proposed the existence of a ``molecular evolutionary clock'', based on evidence that the rate of evolutionary change of molecular sequences appeared to be very similar per unit time across diverse lineages \cite{zuckerkandl1965}. Allan Wilson was a pioneer of the application of the molecular clock and one clock. One  of the first examples of a molecular phylogeny challenging palaeontological evidence came from Wilson and Sarich's paper entitled ``A molecular time scale for human evolution'' \cite{WilsonSarich1969}, in which they estimated an age of the common ancestor of humans and chimpanzees of 4-5Myr, far more recent than the figure of 20-30 Mya accepted at the time by palaeontologists. Nevertheless a few years later Langley and Fitch \cite{LangleyFitch1974} introduced a paper on the molecular clock by saying: