A very special jellyfish was in the news recently…actually the term jellyfish is no longer fully acceptable isn’t it? It isn’t anything like a fish afterall. From now on, please refer to these ethereally beautiful creatures as sea jellies or just plain old jellies. This is just like star fish which are now called sea stars. Generally I like sticking with a name once it has become ingrained (hello brontosaurus) but these name changes are different for obvious reasons.
Back to the jelly…
The name of the sea jelly species in question here is turritopsis nutricula. It has the fascinating distinction of being the only known animal that is potentially immortal.
There are other animals that we know live long long lives with no known upper-limit but this sea jelly does something that none of these ancient vertebrates can do…they become youngsters again and again,
More specifically, they can cycle from their adult stage called a Medusa back to an immature polyp stage again and again.
This fascinating process is called transdifferentiation. When this happens, one type of non-stem cell transforms into another type kinda like a liver cell turning directly into a heart cell. It can also happen when a stem cell that has already specialized itself creates cells different from this specialization.
There are some animals that you have heard of that can do this to a limited degree like the iconic limb re-grower the salamander which can make a new leg on demand. As great as that is, it’s pretty much as far as it can go in that regard. This sea jelly though, affectionately called T Nut, can regrow an entire body. How cool is that.
Because it can cycle from its adult stage back to its immature stage, scientists think there is no limit to its life-span. I wonder if we can apply this knowledge to aid humans in regrowing organs or even whole limbs. My guess is that we couldn’t because their physiology is just too different from ours. Making our whole bodies younger has obvious appeal too but these creatures are in a sense, giving birth to themselves. I wouldn’t want to be young again if it caused my brain to also re-enter a youthful stupid state. For every other organ though…have at it.
Because they don’t die naturally, the numbers of these jellies are spiking. They’re now found in oceans around the globe rather than just in their native Caribbean waters. “We are looking at a worldwide silent invasion,” says Dr. Maria Miglietta of the Smithsonian Tropical Marine Institute.
Perhaps I’ve been wrong all these years about the inevitable robot takeover of human kind.