Another link sent in by Robert – www.livescience.com/preserved-DNA-sampled-sheep-mummy.html …. pristine DNA from a sheep leg found in a salt mine in Iran, carbon dated to the 5th or 6th centuries AD. The DNA was good enough for a genetic investigation. It seems it was discarded by miners – leftover from a meal. However, that has not stopped the extraction of DNA as the salt seems to have mummified the leg. It dates back 1600 years, or nearly so, and it is described as an 'immaculate' preservation. All down to the salt. The mine has a high salt but low moisture environment, capable of preserving skin and hair – and of course, patches of DNA. This is achieved by saprophytic microbes that gorge on dead and decaying organic matter such as meat. Normally, enzymes that break down DNA rely on water to execute chemical reactions. Saprophytes use these enzymes to break down the flesh. However, in the mine the salt molecules bind to water making it unavailable to the enzymes. Soft tissue from human and animal carcasses completely dry out – a sort of natural mummification process. See also www.heritagedaily.com/2021/07/dna-from-1600-year-old-iranian-sheep-mummy… …
Robert also sent in a link to https://crev.info/2021/07/sheep-mummy-shows-limits-on-dna-longevity … where the intention appears to be to show the limits that soft tissue can survive in the fossil record, on the basis the author is a young earther. It's an interesting view but whether or not it shows that dinosaur tissue cannot survive for millions of years or not is something that may have nothing to do with the salt mine preservation. Dinosaurs in sedimentary rocks were mostly drowned and buried in mud, silt, and sand, in the blink of an eye. Rather, that is how a catastrophist would see it. Hence, the preservation of soft tissue, in that case, was entirely different from that of the sheep leg. The point the author of the CREV piece wants to make is that dinosaurs cannot be as old as the mainstream allows – using the sheep leg to show how unlikely it was that soft tissue could survive for so long, as bacteria and enzymes set to work very quickly. Immediate burial would seem to alleviate that point of view. However, mainstream does not necessarily see the dinosaurs being entombed very quickly and the author, therefore, has a point.
The paper itself is at https://royalsocietypublishing.org/doi/10.1098/rsbl.2021.0222 .. or variously https://doi.org/10.1101/2021.04.15.439892 …