> For example, one very important difference is that DNA can be edited and lose history, unlike blockchain, but an intact fossil record could be used to infer how those edits came in over time and space, kind of like an incomplete distributed ledger.

That is a very good point. (I'm intentionally ignoring all the assumption in your preamble, since it doesn't actually further the discussion.)

It is true that editing blockchain completely destroys the chain, and editing DNA in very specific ways does not. I was thinking (when I wrote it) that because of the way the genes interact it can be completely destructive to take only a single piece of DNA. But, as you correctly point out, we do that all the time. So, yes, the blockchain analogy only partially fits.

Thank you.