But AFAIK nobody really believes you'll find readable DNA in there. It just doesn't last more than a couple of million years no matter how carefully you preserve it.
I don't remember which source it was, but I remember they did claim to have (partially) sequenced it, and found that it's nearest living relative was chickens.
EDIT: Reading on I see that if stored at cold temperatures it can last a lot longer.
Yes, though it seems they need to be stable, constant temperatures too. The Denisovans (human related species, ancestors of some of us) are known entirely from 41,000 year old DNA from a cave in Siberia, and the sequence recovered is basically the full genome - as good as for living humans and a lot better than any found for Neanderthals so far.
Honestly, if you're worried about your image the citation to slate isn't the one I would have disclaimed.
That's quite some editorial comment at the end of the crev.info piece:
"""
These claims should be remembered if ancient DNA older than that is confirmed in future finds[...] if intact DNA is found in a dinosaur or other fossil older than the upper limit they just stated, it could have the effect of falsifying the evolutionary timescale. Since evolutionists are such staunch believers, though, most likely the reaction will be, “Well, what do you know; DNA can survive for 65 million years.” [...]
The rest of us should remember what they said beforehand about DNA’s upper limit age, and not let them get away with it.
"""
Now we know -- if you've had result A for hundreds of years, and result B for singles of years, then evidence suggesting that the two conflict clearly supports result B.
EDIT: link to http://crev.info/2013/07/longevity-of-dna-estimated/ (and vacillation about the propriety of citing to slate) was removed even before I posted this reply. It seems to be a nice, on-topic summary of current knowledge on the longevity of DNA, but wow, the editorializing. :/
I really should have taken a second look at what I was citing! I removed that before I saw your comment. For some reason I thought I'd cited some interesting genetics blog. I read the paragraph. Yep. Took a quick look around — looks science-y.
Oops. Bah. My shame. I spat my coffee out when I read the whole article.
On a related note, I really wish HN had a preview feature. I often end up posting & then editing because 1) no preview 2) sessions timing out.
However… Mammoths!?