How does evolution build brains without a blueprint? Terrence Deacon reveals how self-organizing developmental processes, constrained by diffusible molecular signals, generate the neural architecture that natural selection then sculpts through competition and functional use. Subscribe for more from the Convergent Science Network podcast series. Terence Deacon brings the evo-devo perspective to brain science, arguing that understanding how brains are built during development is essential to understanding how they evolved. The core insight is that evolution does not modify adult brains directly , it modifies developmental programs. Since development relies heavily on self-organizing processes at every level, from gene regulatory networks to cell migration to axon guidance, the space of possible evolutionary changes is profoundly constrained by what ...