Injured comb jellies can fuse into a single organism
Comb jellies, technically known as ctenophores, are one of the weirdest creatures on Earth. They appeared in the seas over half a billion years ago and have maintained to the present day the comb-like rows of cilia they used to move around. Their transparent bodies and internal bioluminescence give them looks that rival gaming computers. But there's something that makes them even weirder.
When a comb jelly is injured, it can regenerate at an amazing rate. But it can also attach a body part of another injured comb jelly and integrate it near-seamlessly into its own body. (Those who have played Elden Ring can enjoy comparisons to Godrick The Grafted.)
I've been observing ctenophores for a long time, so it was easy to spot an unusually large specimen. Some of the anatomical features were doubled, so I realized what I'm looking at is actually two individuals that have fused together," said Kei Jokura, a marine researcher at the University of Exeter and lead author of a recent Current Biology paper on the integration of fused ctenophores.