I think that&#x27;s exactly it. The groundwork for &quot;complex&quot; features must already be there in some sense, maybe through mutations or hitchhiking. The last mutation is probably like flipping the on-off boolean. Or maybe something dramatic like a keystone. I.e. the parts alone don&#x27;t do anything, but you have this magical bit flipped that suddenly turns everything on and gives them significance.<p>But yeah one bit&#x2F;mutation does not a feature make. Not without some prior stuff to latch on to, in my opinion.