Effect of Amputation on re-Symmetrization and Physical Behaviors of Cassiopea xamachana

Abstract

The purpose of this experiment was to investigate the physical behaviors and the re-symmetrization rate of the Cassiopea xamachana based on cutting ¼ through the manubrium (center of Cassiopea) versus ¼ amputation not including the manubrium. Jellyfish have four radial root canals, defined as tetramerous radial symmetry, all equally symmetrical. Re-Symmetrization is the process of reorganizing one’s body parts to regain function after a loss of anatomical structure. This process takes approximately four days to complete to regain full function. Cassiopea xamachana swims upside down which is normal for the jellyfish, while swimming right side up and crashing into objects is abnormal. There were two groups: Group A was cut ¼ through the center, and Group B was cut ¼ off center. Each group had seven jellyfish, ensuring that each tank was not too crowded and each tank had similar environments. The jellyfish pre-amputation was used as a control for the Cassiopea’s behaviors. The trial resulted with Group A dying sooner and having a slower pulsation rate than Group B. However, it had a faster re-Symmetrization rate compared to Group B. In conclusion, injury to the manubrium has an effect on the Cassiopea. Limitations of the study included the type of equipment used as the jellyfish were very delicate and finding a way to maintain the ammonia levels overnight and during the weekend. Future work that will be explored will be how different factors such as environmental changes affect their re-Symmetrization rate and physical behaviors.

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