HAVE YOU EVER WISHED you could live a day, or a year, or your life over again?
The idea of Trinidad living multiple lives came from studying the Immortal Jellyfish–the Turritopsis nutricula. This hydrozoan jellyfish form can revert to the polyp stage after becoming sexually mature. It is the only known case of an animal capable of reverting completely to a sexually immature, colonial stage after having reached sexual maturity as a solitary stage. It does this through the cell development process of trandifferentiation.
Theoretically, this process can go on indefinitely, effectively rendering the jellyfish biologically immortal, although, in nature, most Turritopsis, like other medusae, are likely to succumb to predation or disease in the plankton stage, without reverting to the polyp. No single specimen has been observed for any extended period, so it is not currently possible to estimate the age of an individual, and so even if this species has the potential for immortality, there is no laboratory evidence of many generations surviving from any individual.
The Nadirians have a similar life cycle, but they are regenerated to be reborn at sexual maturity (eighteen for them) and begin a forty-year lifespan. If we could learn the secret of trandifferentiation, maybe we could live our life over again like Trinidad.