When we injure ourselves, our bodies will try to repair the wound. But other creatures such as flatworms, and some lizards, are able to self-repair by regenerating new body parts. Jellyfish have a lot of natural predators and are even vulnerable to cannibalism by other jellyfish. They thus require an effective method of self-repair. A recent study on moon jellyfish has revealed a unique healing strategy now known as symmetrisation – a few days after losing an arm, the jellyfish had regained the radial symmetry of its body parts. However, rather than regenerating the lost arm, this was achieved by rearranging the remaining body parts. Pictured are three different species of Scyphozoan jellyfish (top row), the arms on one side were amputated, prompting the jellyfish to rearrange themselves, regaining their symmetry (bottom row). This process is believed to be driven by muscle contraction, and provides insight into different biological self-repair strategies.
BPoD stands for Biomedical Picture of the Day. Managed by the MRC London Institute of Medical Sciences the website aims to engage everyone, young and old, in the wonders of biomedicine. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.
BPoD is also available in Catalan at www.bpod.cat with translations by the University of Valencia.