It is sloppy to use dubious metaphors to describe brains or people. It is egregious to actually believe those metaphors.
"Back a long time ago, everyone thought the world was square. And this guy, he said it was round? So they burned him."
In some cases, such as the horseshoe crab, the coelacanth, or the ginkgo tree, these species seem to have remained virtually the same for hundreds of millions of years.