I'm preparing a manuscript, and I'd like to give credit where it
is due. But I don't know where some ideas which are now second nature
to molecular evolutionists were first aired.
Who first published the idea that, when comparing homologous DNA
sequences which have diverged under selection for the conservation of
the function of an encoded protein, we should expect to see less
variability at first and second positions of codons, but more at the
third positions? And, in the same situation, the similar idea that
synonymous nucleotide differences (synonymous at the amino acid level)
should be more frequent than nonsynonymous nucleotide differences
(which alter the encoded amino acid)?
The idea must have come up after the discovery of the genetic code
and before the neutral theory became popular - I've only managed to
trace it back to the beginnings of the neutral theory. I'd appreciate
any references from those who know the literature better than I do.
dwithers at genetics.utah.edu