

Can some please let me understand how they are finding these miraculous genetic/DNA material long past their normal degradation times and how they are so sure that it belongs to humans or their ancestors? As far as I know DNA has 521 years half-life. So every 521 years you’ll be losin 50% of the viable DNA without doing anything. So, by this math there shouldn’t be any viable DNA in anything past couple thousand years but somehow we are keep finding miraculous DNA all over the place that goes back millions of years. When I read about these findings I see that they are talking about couple base pairs and best ones are talking about 120 base pairs. Considering human genome has over 3 billion base pairs how are these scientists are so sure about their findind?
Thank you for your answer. Correct me if I’m wrong but this sounds like they are doing a lot of guess work in that. I’m really trying to wrap my head around it but basing your findings over 26 modern human populations and going back doesn’t sound like solid way to go since you’re looking for something you have and interpreting it based on that modern data while it can be something else and/or you’re biased (like assuming that you have human DNA from dozen or more base pairs).
Also finding certain mutations sounds good but considering the rarity, the age of these findings, natural degradation and base pair counts in their findings makes it very iffy to believe it’s exactly what they say it’s. How can you be so lucky to find such discerning markers all the time and this consistently? It sounds improbable to me. I might be missing something in-between and I’m trying to find it but so far couldn’t. If you or anyone else knows please let me know. Thanks in advance.