“But basically, the 1 bit/generation bound is information-theoretic; it applies, not just to any species, but to any self-reproducing organism, even one based on RNA or silicon. The specifics of how information is utilized, in our case DNA → mRNA → protein, don’t matter.”
OK, and I’m familiar with information theory (less so with evolutionary biology, but I understand the basics) but I’m thinking that the 1 bit/generation bound is—pardon the pun—a bit misleading, since:
A lot—I mean a lot—of crazy assumptions are made without any hard evidence to back them up. (E.g., the “mammals produce on average ~4 offspring, and when they produce more, it’s compensated for by selection’s inefficiencies.”)
I’m still not convinced that we’re measuring in the right units. Some mutations do absolutely nothing (for example, if a segment of DNA translating to a UAU codon mutated into one translating to UAC), and some make a ridiculously huge difference. This kind of redundancy, along with many other factors, makes me wonder if we need to change the 1 bit by some scaling factor...
Eliezer, I’m a little skeptical of your statement that sexual reproduction/recombination won’t add information...
Single base pairs don’t even code for amino acids, much less proteins. 2. If we’re looking at how a mutation affects an organism’s ability to reproduce, we want to consider at least an entire protein, not just an amino acid. 3. There can be multiple genes that are neutral on their own, yet in combination are either very harmful or very beneficial.
Can you provide an argument as to why none of this affects the “speed limit” (not even by a constant factor?)