ICR.org, 8/18/16, “Fossil DNA in Deep Seafloor Mud” [Excerpts]:
Scientists found DNA in two undersea sediment drill cores from the Bering Sea. The researchers thought the chloroplast DNA (cpDNA) must have come from near-surface light-gathering organisms like diatoms, and not mud-dwelling organisms like bacteria. Discovering cpDNA from dead diatoms near the top of the seafloor presents no challenge, but these researchers found it hundreds of meters down. Long-age believers insist that hundreds of meters of sediment require at least hundreds of thousands of years to deposit. Given that DNA degrades relatively quickly, the team faced the significant challenge of explaining how DNA could persist long enough to get buried beneath that much sediment.
In the journal Geology, the three scientists described the DNA samples that came from various depths. Other researchers gave each an assigned age of over a million years. DNA is not supposed to last that long. Not even close.
The Bering Sea DNA they discovered joins prior finds that similarly challenge deep time. The authors briefly described examples of DNA and RNA preservation from sediments thought to be as much as 2.7 million years old. They wrote, “In general, genetic studies of material that pre-dates the Quaternary [i.e., more than 2.6 million years old] are at odds with the current understanding of DNA preservation, especially in wet environments.”
Clearly, DNA decays in hundreds of years at Earth-surface temperatures, but scientists find DNA that apparently lasted over a million years. How can this be?