That's what I mean by complexity, yeah.

I don't know if I made this was clear, but the point I make is independent of what high level principles explain thing, only that they are high level. The ancestors that competed across history to produce the organism of interest are not small parts making up a big thing, unless you subscribe to causal reductionism where you use causes instead of internal moving parts. But I don't like calling this reductionism (out even a theory, really) because it's, as I said, a species of causality, broadly construed.