>>> it should be possible to directly predict the end sensory result of an input molecule, even without knowing the intricate details of all the systems involved
Maybe we're missing the most interesting aspect. Olfactory Receptor Genes in humans comprise ~1% of the total genome. The benefit here is in understanding how environmental changes trigger beneficial mutations and enhance sensory features.
I doubt the olfactory complex evolves via simple mutations directly on the receptors, but rather on other dna constructs that can quickly (and badly) replicate genes like retrotransposons
if anybody could answer questions like that definitely, it would be a great advance. There is fairly strong evidence that olfaction evolution occurs by gene duplication followed by selection.
Maybe we're missing the most interesting aspect. Olfactory Receptor Genes in humans comprise ~1% of the total genome. The benefit here is in understanding how environmental changes trigger beneficial mutations and enhance sensory features.
https://en.wikipedia.org/wiki/Evolution_of_olfaction