Wild Discovery Reveals That Comb Jellies Can Age in Reverse : ScienceAlert

Sea Walnut Comb Jelly Can Reverse Aging Under Stress, Study Finds

As adults, we often long for simpler times when life gets tough. But for one strange marine creature, reverting to a juvenile stage is not just a wishful thought – it’s a reality. The sea walnut comb jelly, also known as Mnemiopsis leidyi, has joined the immortal jellyfish (Turritopsis dohrnii) in the ability to reverse its physical aging process under extreme conditions.

Comb jellies have always been fascinating creatures with unmatched regeneration abilities. They can fuse together to survive injuries, reproduce sexually in their larval stage, and even adapt their feeding behavior based on their needs. But a recent study has revealed a new dimension to their remarkable capabilities.

Marine biologist Joan Soto-Angel from the University of Bergen in Norway made a surprising discovery when an adult sea walnut in his lab tank transformed into a larva, shedding its mature features. This led Soto-Angel and his colleague Pawel Burkhardt to investigate whether the sea walnut could actually reverse its aging process.

The experiment involved isolating 65 healthy adult comb jellies in tanks and subjecting them to starvation followed by a lean diet of rotifers. The researchers observed that the jellies started shrinking and reabsorbing their adult lobes when stressed. Those that had lobes surgically removed showed even more pronounced signs of reverse aging, resembling cydippid larvae.

Interestingly, only a small percentage of the starved jellies fully reverted to a youthful form, while the injured group showed a higher rate of reverse development. This suggests that stress plays a significant role in triggering the sea walnut’s ability to turn back time.

Collaborator Pawel Burkhardt is now focused on unraveling the molecular mechanisms behind this reverse development and its implications for the animal’s nerve net. The discovery of this unique capacity in the sea walnut comb jelly raises intriguing questions about the prevalence of such abilities across the animal kingdom.

The research, published in the Proceedings of the National Academy of Sciences, sheds new light on the incredible adaptability of marine creatures and their ability to defy conventional aging processes.