Comb Jellyfish Can Reverse Your Aging

Oct. 30 (EUROPA PRTESS) –

A new article published in Proceedings of the National Academy of Sciences (PNAS) reveals the unprecedented ability of a ctenophore, known as a comb jellyfish, to reverse its development.

The findings suggest that Life cycle plasticity in animals may be more common than previously believed.

The life cycles of animals usually follow a familiar pattern of decline with countless variations: they are born, grow, reproduce and die, giving way to the next generation. Only a few species are capable of deviating from this general principle; The best-known example is the “immortal jellyfish” Turritopsis dohrnii, which can revert from an adult jellyfish to a polyp. This elusive group of animals with flexible life cycles now includes the ctenophore Mnemiopsis leidyi.

“The work challenges our understanding of early animal development and body plans, opening new avenues for the study of life cycle plasticity and rejuvenation. The fact that we have found a new species that uses this peculiar ‘time travel machine’ raises fascinating questions about how this ability spreads across the tree of animal life,” said Joan J. Soto-Angel, a postdoctoral researcher on the Manet Team in the Department of Natural History at the University of Bergen.

The remarkable discovery began by chance. While observing animals in the laboratory, Soto-Angel noticed that an adult ctenophore had disappeared from a tank, apparently replaced by a larva.

Curious to discover whether they could be the same individual, he and Pawel Burkhardt, group leader at the Michael SARS Center at the University of Bergen, designed experiments to try to reproduce this possible reversal under controlled conditions. When exposed to the stress of starvation and physical injury, Mnemiopsis leidyi demonstrated an extraordinary ability to transition from its lobed form to a cydipid larval stage.

“It was fascinating to watch them slowly transform into a typical cydipid larva, as if they were going back in time,” Soto-Angel recalls. “Over several weeks, they not only changed their morphological characteristics, but also showed feeding behavior completely different, typical of a cydipid larva”.

The study extends the known developmental flexibility of ctenophores and positions Mnemiopsis leidyi as a valuable model for future research in developmental biology and aging. Since ctenophores are among the earliest animal lineages, the findings suggest that reverse development may represent an ancient characteristic in the animal kingdom.

“This is a very exciting time for us,” Burkhardt said. “This fascinating finding will open the door to many important discoveries. It will be interesting to reveal the molecular mechanism that drives reverse development and what happens to the animal’s nervous network during this process.”