Contrary to how certain organisms cope with a loss in their bodily faculty through regeneration, the moon jellyfish simply rearrange their remaining limbs to regain their symmetry.
CalTech researchers name this survival process as “symmetrization”, culled from the word symmetry, a process that allows these translucent sea creatures to realign their limbs so they could carry out their functions such as moving and eating. Symmetry is indispensable to the survival of jellyfish.
Michael Abrams, a CalTech graduate student and lead researcher inputs: “What we found was that they rely on the mechanical forces generated by their own propulsion machinery, [which is] their muscle and the viscoelasticity of their jelly material.”
The research team studied some 500 organisms from four different species of the jellyfish. They cut off one to seven limbs of ephyra or young jellyfish and observed how the entire process of symmetrization was completed within two to four days. Those jellyfish who successfully completed the process matured into adults while those who failed to achieve symmetry, around 15 percent, did mature but with abnormalities.
“It broadens our understanding of the self-repair mechanism,” Abrams commented. He adds: “So maybe we think about self-repair a little differently. It’s not always about regeneration and regaining lost parts.”
Extending the depths of their study just a bit more, the researchers added magnesium to the disjointed jellyfish’s seawater. They found out that this slowed down the sea creatures’ reorganizing of its parts. However, when magnesium levels were decreased, the jellyfish completed the symmetrization faster.
Abrams explains: “With each pulse of the arm, they contract their arms. “That pulls their material in and that means there’s higher pressure of material that pushes against itself and repels against each other.” “The jelly material facilitates the process,” Abrams added.
This discovery appeared this week in the journal Proceedings of the National Academy of Sciences.