fossil DNA

7 Aug 2016

At http://crev.info/2016/08/fossil-dna-stuns-geologists/ ... the link is provided by Robert Farrar and concerns an open access paper in the journal Geology that documents the existence of DNA in ocean bottom sediments up to 1.4 million years of age. Not sure if this is a straw man argument but the claim is that scientists expressed surprise - as DNA is not supposed to last that long. However, it was preserved in bottom sediments, under water, and this might be a mitigating factor. After all flesh and organic material is preserved for thousands of years in wet peat environments - and ocean sediments have the added factor of being located beneath a lot of water. The DNA is also not your everyday DNA so to speak, it is termed cpDNA and is preserved in a particular kind of algae. I'm guessing a mountain is being made about a mole hill. According to the author DNA is supposed to dissipate after 100,000 years. Does this mean that the ocean sediment core is much younger than geochronology allows? I might also add - the core was taken from the Bering Sea. Was this open water during the last Ice Age? and how far from the Bering land bridge was the core taken?

The full article is available at http://geology.gsapubs.org/content/44/8/615.full