Developmental growth rate plasticity drives organ morphology self-correction after injury

Control of organ size requires tissue-level instructions on cell behavior, especially upon injury. However, the mechanisms utilized by cells to promote organ growth rate adaptation, ensuring proportional sizes and shapes, remain poorly understood. Here, we uncover that organ morphological robustness to perturbations relies on self-correction mechanisms that can bypass developmental genetic defects. By developing precision-microsurgery in developing zebrafish larval pectoral fins, we identify a dynamic adaptation of this organ’s growth rates: while jointly driven by global cell proliferation and extracellular spacing, upon injury, growth becomes uncoupled across tissues and the fin’s axes. These dynamics scale with the amount of injured tissue, restoring organ size and structure without compromising developmental growth rates. Connecting these observations with a mathematical model, showed that the fin area is tightly controlled to a target size, indicative of positional information cues active in the tissue. Our work reveals how cells adapt context-specific growth mechanisms to restore organ proportionality.