Understanding the emergence of (functional) geometry from genetics is one of the great challenges of biology. I will describe how simple physical principles associated with active growth and flow are beginning to help illuminate multicellular tissue morphogenesis in such instances as laying out the body plan, e.g. gastrulation, body elongation, and creating functional organs e.g. guts, brains, and beaks. Combining experiments and theory allows us to link molecular genetics to morphogenesis in a developing organism and construct evolutionary phase diagrams across organisms, while raising new questions in physics and mathematics