Carving Embryogenesis at Its Joints

Abstract: Embryogenesis entails self-organizing forces, flows, and cell fates with robust information expansion and error correction to give an embryo form and function. We quantify and compress morphogenetic flows in early embryos into their fundamental kinematic units: attractors and repellers constituting the “Dynamic Morphoskeleton” (DM). By leveraging the DM to guide new experiments and develop mechanistic continuum models, we have uncovered the mechanistic origin of the attractor in avian gastrulation and controlled its shape, inducing gastrulation flows in avian embryos that are typical of other vertebrates. We have also identified independent mechanistic origins for each of its two repellers, which we can separately eliminate in models and experiments. Our results reveal a remarkable modularity in embryogenesis, delineated by the DM, and offer new perspectives for making sense of complex morphogenetic processes with implications for morphological evolution and control in the emerging science of synthetic morphogenesis.