What happens when an animal is injured and loses important structures? Some animals simply heal the wound, while others are able to regenerate lost parts. Here we show a new strategy of self-repair, where moon jellyfish respond to injuries by reorganizing existing parts, and rebuilding essential body symmetry, without regenerating what is lost. Specifically, in response to arm amputation, the young jellyfish of Aurelia aurita rearrange their remaining arms within 12 hours to 4 days. We call this process symmetrization. The eight armed organism depicted here was not injured, but the rest of the organisms have had one or more arms amputated. Each of them, no matter how many arms were removed, rapidly formed new radial symmetry. Therefore, the full image depicts the spectrum of symmetrization, and the incredible flexibility of life.