Converging Minds and the Evolution of Brains for Complex Cognition

The famous evolutionary biologist Stephen Jay Gould famously remarked that “…if the tape of life could be rewound under the same conditions, evolution could take a very different course, and the human mind would not arise again, even if life’s tape could be replayed a thousand times”. In contrast, his contemporary colleague Simon Conway Morris wrote that “convergence hints at the existence of a deeper structure to biology… The evolutionary routes are many, but the destinations are limited”. Decades after this dispute, we increasingly discover that indeed the destinations of evolution are much more limited than previously assumed. At least, when it comes to cognition. Just take this: Great apes like chimpanzees command complex cognition and have a large neocortex. In comparison, birds like corvids and parrots have much smaller brains and no neocortex. This should cast a dim prospect on their cognitive abilities. But studies of the last two decades revealed that there is not a single cognitive ability of chimpanzees (brain weight 400g) that was not also demonstrated in corvids and parrots (brain weights 3-25g). How is that possible? This question keeps me awake because it challenges core assumptions on the evolution and the neural fundaments of complex cognition. Meanwhile I realized that I must travel back into the deep time of vertebrate evolution to find answers. This talk is about this journey.