Going out of my comfort zone to show you something really cool in Biology and Genetics — the “Immortal Jellyfish”.
Ever wish you could live forever? This jellyfish, scientifically known as turritopsis dorhnii, can potentially do just that. I came across an article about this a few months ago, and couldn’t believe what I had just read. This species of jellyfish can literally revert back to its baby form when stressed, and can do it as many times as it wants. Pictured below from an article in National Geographic in the jellyfish’s adult and younger state:
Photos are courtesy Maria Pia Miglietta and Stefano Piriano (inset). According to the article, “When stressed, the tiny jellyfish’s cells transform, returning the animal to its youthful polyp state (inset). Attached to the seafloor or another hard surface, the jellyfish polyp can spawn hundreds of jellyfish that are genetically identical to it.”
These jellyfish don’t necessarly live forever (or at least, there’s no direct evidence that they do) or always clone themselves. In fact, they often die and reproduce like normal jellyfish. But they have an advantage–if certain problems arise, such as physical damage, they can just revert back to the polyp form, which develops into a colony of polyps. This is essentially the first stage of their normal life. They transform all of their cells, in a way which sounds to me a lot like stem cells–“muscle cells can become nerve cells, or even sperm or eggs.” This process is called transdifferentiation, and surprisingly isn’t unique to these jellyfish. Some animals can undergo partial transdifferentiation, which allow them to regenerate limbs or organs. The reason is it so amazing in this case is that the turritopsis dohrnii can undergo transdifferentiation in order to regenerate its entire body. It’s easy to see why there are so many of these around, and why their population is booming!
These jellyfish are super small–about the width of a person’s pinky nail. It wasn’t until the 1990’s that they knew about this jellyfish’s ability, approximately 110 years after it had been discovered! I don’t know about you, but I think this is pretty awesome! Imagine if human’s had this ability? Actually…I don’t think I’d want to see a world like that. It might be scary.