When a juvenile moon jellyfish loses tentacles, it rapidly reorganizes its remaining limbs to maintain symmetry, a new study says.

In the lab, researchers removed the tentacles from the translucent jellyfish. “Each time, they would start reshaping and reorganizing their bodies,” said Michael Abrams, a biologist at California Institute of Technology and an author of the new study.

The process was quick, beginning 12 hours to four days after researchers removed the tentacles. Mr. Abrams and his colleagues describe their findings in the current issue of Proceedings of the National Academy of Sciences.