Even so, I'm surprised there'd be much of a cockroach left after 500 years or so. Presumably, they were in a well protected part of the wreck not exposed to flowing water. After water rushed in it must have essentially stayed there and any oxygen in it absorbed by nearby wood, etc. and not replaced.
Similarly, with the cat DNA. It would be interesting to know the exact circumstances of how they were found.
isn't there oxygen in H2O ?
There's very little free oxygen in the water below certain depths, actually!
Interesting, thanks!
The oxygen inside water molecules is chemically bound and not really available for other work.
Water does carry dissolved gases like O2 gas, but as sibling pointed out, not at these depths.