I think that the revolutionary innovation embodied in our brains is to create external abstract structures, what Dawkins called the "extended phenotype", and that the torch of evolution has been handed off from biology to sentience.

Our organic brains have remained essentially unchanged for (depending on the theory) 50,000 to two million years, while the nonphysical structure of human civilization has evolved quickly and at an exponential rate; and through the tool of civilization, our grasp of technology and our power to influence our environment have exploded. It's as if the development of biological life has been recapitulated in the blink of an eye in the development of human abstraction, from zero to today. Our brains are a tool for further evolution beyond the limitations of biology...for better or worse. We also have the power to propel ourselves into an evolutionary dead end in a matter of just years.

We live in interesting times.