&gt; That and the standard narrative is just weird. We know from the fossil record that humans have had large craniums and by extension complex modern brains for at least hundreds of thousands of years. What the heck were we doing for all that time? Saying civilization is only ~10k years old is like saying &quot;birds have had wings for millions of years but they only recently started flying.&quot;<p>That&#x27;s nonsense, brains don&#x27;t exist to enable globe-spanning civilisations (nor do globe-spanning civilisations require it as argentine ants demonstrate).<p>What the heck were we doing for all that time? Surviving at all was a big one (and there&#x27;s suggestions of serious population bottlenecks before we got out of africa), then there was spreading throughout the planet, and then the ratcheting of ideas requires that people who could have ideas have the leisure to have and apply them so you need a certain population density and preexisting social complexity.<p>You could just as well wonder what we were doing for the first 10000 years of civilisation (or whatever) and why it took so long to invent computers so there must have been something fishy going on. Or look at the Antikythera mechanism and wonder what the hell we&#x27;ve been doing with those complex computery brains that we didn&#x27;t get to programmable automation and computers for 2000 years.