Suppose I design my Pikachu. It has a terabyte of DNA. And it’s replication mechanisms are accurate enough that 90% of it’s children are mutation free.
Now suppose that any mutation is instantly fatal. I implemented some elaborate system of checksums and kill switches.
This is stable.
Now suppose that, by some oversight, the DNA-polymerase is not error checked.
A mutent Pikachu appears, with a change in DNA-polymerase that causes P(mutation)= 50%.
But half of this Pikachu’s children die of a mutation. So this is still stable.
But if I didn’t put in any checksum, and most of the DNA is managing cosmetic details, then the mutation rate can increase, and generations of increasingly wonky Pikachu can be born.
Wouldn’t this hold in general? If the chance of a lethal mutation is small, there is little downside to increased complexity. If the chance of a lethal mutation is large, a better DNA-polymerase is a substantial advantage.
I’m not convinced by the Pikachu example.
Suppose I design my Pikachu. It has a terabyte of DNA. And it’s replication mechanisms are accurate enough that 90% of it’s children are mutation free.
Now suppose that any mutation is instantly fatal. I implemented some elaborate system of checksums and kill switches.
This is stable.
Now suppose that, by some oversight, the DNA-polymerase is not error checked.
A mutent Pikachu appears, with a change in DNA-polymerase that causes P(mutation)= 50%.
But half of this Pikachu’s children die of a mutation. So this is still stable.
But if I didn’t put in any checksum, and most of the DNA is managing cosmetic details, then the mutation rate can increase, and generations of increasingly wonky Pikachu can be born.
Wouldn’t this hold in general? If the chance of a lethal mutation is small, there is little downside to increased complexity. If the chance of a lethal mutation is large, a better DNA-polymerase is a substantial advantage.