After yet another bout of late-night bleary-eyed thought, I've got some additions to last night's post. Hopefully, I can flesh them out in more detail when I'm not half asleep.
I've thought of at least two more factors that need to be considered. Genomic size may help to compensate for some of the evolutionary losses brought about by focus on individual survival rather than species-level diversity/selection. After all, the sheer number of polymorphisms/combinations is much higher with the larger genomes of more evolved animals. This would mean that each individual is a walking repository of much more genetic diversity than less evolved species... I think. Yet I'm not sure that this matters that much: genome size seems to 'saturate' at some point, and there is not a direct correlation between genomic size and 'individual focus', for lack of a better term.
Another bit deals with levels of genomic regulation. I haven't thought this out carefully yet, but it is clear that higher species have much more complex levels of regulation of gene expression. This allows for a much finer 'tweaking' control of evolutionary factors. Does this matter in the long run, if most humans survive to reproduce? I'm not sure. But something at the back of my head was nagging me about it, so I'm tossing it out there for discussion.
What I would really love is if I could find some hard data on all of these factors to adequately weigh them against each other. I'd like to see studies of genetic diversity of various types of species over time, with and without selective pressures, a look at mechanisms of controlling litter size, etc. Maybe I can try cornering some evolutionary geneticists I know and get some answers.
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