TED-ED: Jellyfish predate dinosaurs. How have they survived so long? - David Gruber

Jellyfish are ancient, diverse sea creatures with unique abilities. They lack a brain but have a simple nervous system and can propel themselves by contracting their bell. Some jellyfish have potent venom, while others glow due to GFP, a compound used in scientific research. Jellyfish have existed for over 500 million years and thrive in changing oceans. The immortal jellyfish can revert to a juvenile state, effectively bypassing death.

What role does green fluorescent protein (GFP) play in scientific research?

How long have jellyfish been inhabiting the oceans?

What adaptations allow jellyfish to thrive in changing ocean conditions?