Our brains have very exceptional genetics as evidenced by their exceptional complexity. That humans can live so long with a high metabolism is another indication of genetic complexity. The reason for our long lifespan, well past breeding years, is due to the advantages of having wise people around in war. If two tribes go to war, the side with more wisdom and life experience has a substantial advantage. Most human qualities can be traced back to their advantage in war.
The "advantage after a hurricane" is more likely. Not too long ago a tribe could hold a war and no one would come even if the invitations were sent out decades earlier. Just weren't enough people around.
That doesn't indicate greater genetic complexity. You can get more complex brains with simple variations to the default program, like letting the brain simply grow larger, or longer, or delaying cell death, etc.
The flip side of that is child rearing. A tribe that has grandmothers has an advantage over a tribe that does not -- in part because of their wisdom, and in part because having grandmothers to care for older children frees up the younger women to have more babies.