Gonna have to agree that at the very least, the immune system is way up there! After reading Philipp Dettmer's book "Immune" (recommended), I couldn't help but think, "Wow, the API and protocols that this thing has..."
This - the immune system is fiercely complex, and as I understand it there's reason to believe we don't yet know all the types of cell that are in it. I could be wrong about that - I'm not an immunologist - but seem to recall reading such in the last few years.
> The research group behind the current study previously showed11 that NHEJ <non-homologous end-joining, an error-prone mechanism of double-strand DNA break (DSB) repair> is essential for NSPC <neural stem/progenitor cells> differentiation, which implies a role for NHEJ-mediated DSB repair during normal brain development. It is possible that subpopulations of cells in the brain display the same types of rearrangements, and that some are positively selected. Similar studies in vivo and in other tissues are needed to test this hypothesis.
> We show that genome-wide maps of endogenous DSBs are highly correlated between experimental replicates up to 10 kilobases (kb) resolution, and that DSBs are non-uniformly distributed along the genome, in all three cell differentiation stages analyzed.
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> Our datasets and analytical tools represent a valuable resource for exploring genome fragility during human neurogenesis and investigating how this might contribute to the pathogenesis of NDDs. <neurodevelopmental disorders>
If the rules that govern intelligence are simple (and intuition tells me they are), then the immune system is certainly a complicated and prickly beast.
immune system cells actually share a lot of the same receptor systems as neurons do, and these systems end up influencing each other to significant degree, both ways.
