|Sinninghe Damsté,J.S. and M.J.L. Coolen, Fossil DNA in Cretaceous Black Shales: Myth or Reality?, Astrobiology 299-302, 2006|
In summary, we believe that the claim of Inagaki et al. (2005) should be examined by analysis of molecular fossils from the black shales studied by these authors before the existence of fossil DNA in Cretaceous black shales can be accepted. The jury is still out. We also believe that much more work on fossil DNA in sediments much younger than Cretaceous has to be undertaken to assess, in as complete a manner as possible, the potential and potential pitfalls of the analysis of fossil DNA in sedimentary sequences. Unrealistic claims of fossil DNA in old sediments will have a negative effect on the development of this emerging new field in Earth Sciences. Full text of article is available here.