This interesting NY Times article, “Can a Jellyfish Unlock the Secret To Immortality,” (Nov. 28, 2012) by Nathaniel Rich tells the story of hydrozoans, small invertebrates that, depending on their stage in the life cycle, resemble either a jellyfish or a soft coral and Shin Kubota the eccentric marine biologist that studies them.
Kubota is devoted to studying these Turritopsis medusa or “immortal jellyfish” for their amazing ability to re-create themselves. The author writes, “The world’s only captive population of immortal jellyfish lives in petri dishes arrayed haphazardly on several shelves of a small refrigerator in Kubota’s office. Like most hydrozoans, Turritopsis passes through two main stages of life, polyp and medusa. A polyp resembles a sprig of dill, with spindly stalks that branch and fork and terminate in buds. When these buds swell, they sprout not flowers but medusas. A medusa has a bell-shaped dome and dangling tentacles. Any layperson would identify it as a jellyfish, though it is not the kind you see at the beach. Those belong to a different taxonomic group, Scyphozoa, and tend to spend most of their lives as jellyfish; hydrozoans have briefer medusa phases. An adult medusa produces eggs or sperm, which combine to create larvae that form new polyps. In other hydroid species, the medusa dies after it spawns. A Turritopsis medusa, however, sinks to the bottom of the ocean floor, where its body folds in on itself — assuming the jellyfish equivalent of the fetal position. The bell reabsorbs the tentacles, and then it degenerates further until it becomes a gelatinous blob. Over the course of several days, this blob forms an outer shell. Next it shoots out stolons, which resemble roots. The stolons lengthen and become a polyp. The new polyp produces new medusas, and the process begins again.”
Kevin J. Peterson, a molecular paleobiologist who contributed to the Genome Project says, “There’s a shocking amount of genetic similarity between jellyfish and human beings.” He goes on to explain the implication in this, “If I studied cancer, the last thing I would study is cancer, if you take my point. I would not be studying thyroid tumors in mice. I’d be working on hydra.”
Rich writes that Hydrozoans, may have made a devil’s bargain. In exchange for simplicity — no head or tail, no vision, eating out of its own anus — they gained immortality. These peculiar, simple species may represent an opportunity to learn how to fight cancer, old age and death.
*photo Takashi Murai
you can read the entire article at: