Immortal Jellyfish: The Science of Falling in Love Again
As hearts turn toward promises of forever on Valentine's Day, a Texas A&M University at Galveston researcher examines how the blueprint for eternal love may be hidden in the life of a tiny jellyfish.
Every February, Valentine’s Day encourages couples to promise eternal devotion. We often think of love as something fragile or finite; many see it as a spark destined to dim once routine sets in. Just in time for the season of hearts and flowers, an ant-sized jellyfish named Turritopsis dohrnii shows that a relationship doesn’t have to end just because it has grown old: Instead, it can revert to a state of fresh potential and begin anew. The immortal jellyfish is a hopeful reminder that forever may not be a fantasy at all, but a biological possibility.
It is largely through the scholarship of Dr. Maria Miglietta, associate professor in marine biology at the College of Marine Sciences & Maritime Studies at Texas A&M University at Galveston that scientists have uncovered T. dohrnii’s extraordinary biological “immortality”. With 20 years of experience studying jellyfish and a Ph.D. in biology, Miglietta is one of the few experts capable of consistently finding the ant-sized T. dohrnii in the wild. Although she has studied at institutions like Duke University, Notre Dame, and even the Smithsonian in Panama, she proudly considers Texas A&M University at Galveston her home.
“I am one of the only people working on the immortal jellyfish,” said Miglietta. “They are hard to study in many ways—even just going out in the field and recognizing the jellyfish is something very few people in the world can do.”
T. dorhnii’s size isn’t all that makes it atypical. Typical jellyfish live only one life: It starts as a larva, settles as a polyp (a plant-like stalk), and eventually blooms into the free-swimming, tentacled medusae that many envision when thinking of jellyfish. After reproducing, most medusae die.
Rather than ending its life, T. dohrnii renews it — resetting its cellular development while retaining its original genetic identity. When faced with starvation, physical injury, or the simple aging of its tissues, the medusa doesn’t perish: The entire jellyfish collapses into a cyst-like ball and falls to the ocean floor to become a polyp again, beginning its life cycle anew.
While in this cyst-like state, the specialized cells of the jellyfish undergo a process called transdifferentiation. Any specialized cells—such as those meant for swimming or digestion—essentially “forget” what they are and transform back into stem cells. Stem cells can then develop into many different cell types. The process of transdifferentiation is what allows the cells of the jellyfish to reset and regrow into a free-swimming medusae again.
T. dohrnii is capable of surviving damage that would kill other organisms, according to Miglietta: “Even if you starve it, bring it to 100 degrees Celsius, cut it, or even use UV light—things that would normally kill an animal—it doesn’t die.”
The immortal jellyfish retains its original DNA when going through this cycle, and so do the multiple new medusae that bloom from its polyp during the renewed life cycle — meaning they are near-perfect genetic clones of the original jellyfish. They are able to do this without a brain, nervous system, lungs, or any dedicated organs for this biological immortality.
“When the season is right, one T. dohrnii polyp can bud off multiple jellyfish,” said Miglietta. “So from one jellyfish that doesn’t die, you can have hundreds of new jellyfish injected into the environment.”
While the method by which this jellyfish achieves immortality isn’t fully understood yet, Miglietta’s research has been pivotal in moving T. dohrnii from a niche biological curiosity to a promising path for regenerative study in humans. Her research explores how these creatures achieve “life-cycle reversal,” a feat that seems to defy the very laws of biology.
“Understanding how cells can reprogram themselves to become something else that is needed is at the base of regenerative medicine,” Miglietta explained. “And this jellyfish is the only creature that can do it in less than 24 hours.”
This rare life‑cycle reversal provides a striking metaphor for long-term relationships. The jellyfish show that love doesn’t need to end simply because it has matured. Starting over doesn’t require starting from scratch. Renewal can occur without erasing history — a return to possibility, not a goodbye.
Through Miglietta’s research at Texas A&M University at Galveston, the immortal jellyfish becomes more than a marine curiosity. It becomes a scientific Valentine from the sea: a reminder that longevity — whether in nature or in love—is not defined by permanence alone, but by the capacity to renew and begin again.
Toni Mooney Smith| Office of Marketing & Communications
Texas A&M University at Galveston| [email protected]