““It all starts with the fact that thinking is expensive from the standpoint of natural selection,” Mitchell continues. “The brain consumes 20 percent of the calories that humans eat. And while intelligence enabled humanity’s survival, our ancestors were in a constant race against starvation, too. So their brains only got so big.” Pugwash gets it. “Being smarter gets you more to eat but only up to a point,” he says. “Then there’s diminishing returns.” Mitchell nods. “And if human brains devoured double the calories, grandma and grandpa wouldn’t have found twice the nuts and berries. So our ancestors’ brains grew until they hit a certain equilibrium.” “Which means humans are a lot stupider than maybe they could be. Which explains Republicans.””
