The Extraordinary Talent of Comb Jellies
Glowing marine creatures known as comb jellies possess an extraordinary talent: when injured, two individuals can merge seamlessly into one without experiencing the tissue rejection seen in most animals. Even more fascinating, their nervous systems combine, and their digestive tracts unite to share food. Researchers note that this unique adaptation has not been observed in any other species before.
What Are Comb Jellies?
Comb jellies, also known as ctenophores, are soft-bodied marine invertebrates that move using hair-like cilia. Despite their simplicity, they possess muscles, nervous systems, and sensory organs. Due to their delicate structure, they are challenging to study, leaving much about them still unknown.
A Groundbreaking Study
In a study published in Current Biology, researchers noticed a missing warty comb jelly during routine experiments. They discovered that one remaining jelly was actually two fused together with no clear separation. Suspecting this fusion was due to injuries, they tested it by removing small body sections from 20 jellies and placing them near each other. Nine pairs successfully fused, with the researchers noting that the injuries were minor compared to what jellies might encounter in the wild.
Rapid Fusion and Integration
Injured comb jellies fused within 24 hours, with their nervous systems syncing up quickly and responding to stimuli across their combined body. Researchers confirmed their stomachs also merged by feeding them fluorescent shrimp. Although they behave as a single organism, they retain separate DNA and cannot pass on this fused form to offspring; however, researchers still describe them as “single entities” in their study.
Implications for Science
This discovery could help scientists understand how immune systems evolved. It may explain how they differentiate an organism’s own tissues from those of others. The researchers plan to study another comb jelly species, Bolinopsis mikado, to see if they can also fuse.
