Comments
TheManInTheShack t1_j27szcw wrote
Not bones but even better. Scientists found soft tissue from dinosaurs that was 75 million years old.
loki130 t1_j28abjz wrote
That claim has met with a lot of controversy, and even accepting it, these are like microscopic fragments of heavily degraded material.
TheManInTheShack t1_j28io39 wrote
Interesting. At the time I don’t remember them being described as microscopic. But it was many years ago.
AllanfromWales1 t1_j27z728 wrote
Can't speak for bone, but the bases of trees in a forest which is drowned due to sea level rise can remain as wood for many thousands of years. I suspect that in waterlogged but not anaerobic conditions the same would be true of bone.
AllanfromWales1 t1_j280zjm wrote
On a similar note, bog bodies up to 10000 years old have been found preserved ("mummified") without fossilisation.
[deleted] t1_j287tmi wrote
[removed]
Faelwolf t1_j2893k0 wrote
Some Dinosaurs have been found partially unfossilized, one even in a fully non-fossilized state, with even the skin pigment preserved (mummification). It all depends on the circumstances surrounding it's burial over time. Of course, such finds are exceedingly rare.
You may find this of interest: https://en.wikipedia.org/wiki/List_of_dinosaur_specimens_with_preserved_soft_tissue
[deleted] t1_j298szx wrote
[removed]
jellyfixh t1_j29kaaw wrote
Fossilization is strictly the process where minerals have replaced tissue and bone, so as long as mineralization doesn’t happen you could have a bone as old as you want. It’s just hard to find them in nature because bone and tissue decays unlike minerals unless something like amber is involved.
Worthyteach OP t1_j2agghn wrote
I was wondering if the situation which would naturally preserve bones would end up causing fossilisation so if there is a limit in nature. Hadn’t thought of the amber angle, So potentially the tail of the dinosaur that was preserved in amber might still be bone?
atomfullerene t1_j2bcqhz wrote
Things that aren't yet fossilized are usually referred to as "subfossils" , which is probably how you want to search for this information
Anyway, I did some research and here's some things I found
This paper describes camel bones from about 3 million years ago on Ellesmere Island. They are embedded in layers of leaf and moss that are described as "subfossil" and the bones themselves were fresh enough to allow the removal of significant collagen for analysis. There have been reports of even older collagen/soft tissue, but that's in bones that have clearly been fossilized. I'm guessing these bones are closer to what you are talking about, given the context of their preservation.
Here's a similar study from the same area looking at beaver teeth and local vegetation, comparing isotope ratios to see what beavers were eating. So we are talking about plant and animal remains that still have organic material that isn't too heavily modified.
Finally, here's a paper that managed to snag DNA from mammoth teeth slightly more than a million years old. That's less than the previous studies, but DNA is more fragile than collagen, so we are talking better preserved specimens here.
Anyway, the answer is probably "A few million years, and you find them in frozen sediments"
Although who knows what might be frozen under the ice at the bottom of Antarctica