> Is there a better article we could link to? "Mother Nature gave RNA editing a try, found it wanting, and largely abandoned it" ... "it looks like cephalopods didn't get the memo" What is that supposed to mean?
The transcription process is DNA -> RNA -> Protein. In the vast majority of living systems mutations happen at the DNA and DNA -> RNA transcription levels, but once you've got RNA it's a relatively straight path to proteins. It's possible to edit RNA but quite unstable and fiddly, so most living systems only make limited use of it, and their "RNA edition pipeline" is quite fixed and limited.
coleoids however apparently edit RNA to an extent unknown of elsewhere, seemingly trading that off for DNA-based evolution: for RNA edition to keep working properly, the source RNA has to be pretty stable otherwise you're building on quicksand, that means DNA mutations will break RNA editions and thus probably viability.
Think of it this way: DNA is source code, RNA is compiler IR and proteins are object code.
Most species edit the source code, they can have optimisation passes on the IR (RNA edition) but it can't be too extensive because the pattern matching will easily break if the source changes too much, and that might break the software entirely.
However coleoids do most or all their coding as optimisation passes working on the IR. And the more these IR passes do, the more they rely on the source code not changing because all of a sudden your "optimisation" passes don't work anymore and it turns out they're absolutely critical to the software working.
The octopus is editing its RNA to deal with different temperatures. Sounds like an overly dramatic way of doing it. Maybe instead of using an `#ifdef TEMP_THRESHOLD 15`
they should have used a `int temp_threshold = 15;`
The transcription process is DNA -> RNA -> Protein. In the vast majority of living systems mutations happen at the DNA and DNA -> RNA transcription levels, but once you've got RNA it's a relatively straight path to proteins. It's possible to edit RNA but quite unstable and fiddly, so most living systems only make limited use of it, and their "RNA edition pipeline" is quite fixed and limited.
coleoids however apparently edit RNA to an extent unknown of elsewhere, seemingly trading that off for DNA-based evolution: for RNA edition to keep working properly, the source RNA has to be pretty stable otherwise you're building on quicksand, that means DNA mutations will break RNA editions and thus probably viability.
Think of it this way: DNA is source code, RNA is compiler IR and proteins are object code.
Most species edit the source code, they can have optimisation passes on the IR (RNA edition) but it can't be too extensive because the pattern matching will easily break if the source changes too much, and that might break the software entirely.
However coleoids do most or all their coding as optimisation passes working on the IR. And the more these IR passes do, the more they rely on the source code not changing because all of a sudden your "optimisation" passes don't work anymore and it turns out they're absolutely critical to the software working.