Turritopsis

Maria Pia Migletta is a marine biologist and an associate professor at the University of Texas at Galveston.

She's been studying jellyfish for decades, especially a species called Turritopsis durorni.

It's nicknamed the immortal jellyfish because it can transform from an adult back to a younger form in as little as 24 hours when it's injured, starving, or stressed.

And this was discovered entirely by accident in the 90s.

The legend says that this scientist was keeping Turritopsis in the laboratory, the jellyfish, and then he forgot to feed them during the weekend.

So without food for a few days, they usually die because they're very small.

But when he came back to the lab on the Monday, he found in the container not the jellyfish anymore, but they revert to a juvenile form, the polyp.