This column is part of a series where Verge staffers post highly subjective reviews of animals. Previously, we've written about animals without telling you whether they suck or rule. We are now rectifying this oversight.

In medieval bestiaries, every animal is imbued with symbolic meaning that reflects God's plan for the world, but the monks that made these compendiums didn't know much about jellyfish-- especially one as unusual as Turritopsis dohrnii, better known as the immortal jellyfish. The bestiaries tell us that the fox is deceitful and cunning: it plays dead to remind us that the Devil hides in plain sight. They say that the turtledove is faithful and mourns its mate after they die; just like the Church stayed true to Christ after his crucifixion. What would they have made of a tiny animal no bigger than a dime, with no brain, no heart, no central nervous system, in fact, barely any motive power at all, but that-- theoretically-- lives forever. The lesson we should take from the immortal jellyfish? We're trying too hard. We Need if we want to beat entropy. To. Chill.

When faced with old age, sickness, or trauma, it simply ages backwards

In medieval bestiaries, every animal is imbued with symbolic meaning that reflects God's plan for the world, but the monks that made these compendiums didn't know much about jellyfish-- especially one as unusual as Turritopsis dohrnii, better known as the immortal jellyfish. The immortal jellyfish doesn't live forever by simply persisting at some magical low-level intensity. The immortal jellyfish can still die, of course, in the violent and exciting ways the ocean has to offer (mainly getting eaten by strange fish and relatable dugongs). Turritopsis dohrnii's staying power is only more impressive when you look at the jellyfish phylum as a whole (which is bending the rules a little for the Review, I know, but it's necessary in order to properly take in the species' genius). If the bestiaries had known about jellyfish, they probably would have just given up trying to extricate God's meaning from the natural world and just worshipped the jellies instead.

"Among the world's most successful organisms.".

Jellyfish blooms-- vast spawnings of jellies in short periods of time-- are on the rise around the world. That's troublesome, because jellyfish can be astonishingly destructive in large numbers., biologist Lisa-ann Gershwin describes how the species has crippled national economies by wiping out fishing stocks and delivered blackouts to millions in the Philippines by clogging up water intake vents in nuclear power plants.

Turritopsis dohrnii's staying power is only more impressive when you look at the jellyfish phylum as a whole (which is bending the rules a little for the Review, I know, but it's necessary in order to properly take in the species' genius). Jellyfish have been around for at least half a billion years; the fossil record tells us they predate the evolution of teeth, claws, or even bones. They're hardly having a tough time adapting to modern environs, though: thanks to a combination of overfishing, global warming, and an influx of chemicals and trash, they're thriving.

The immortal jellyfish doesn't live forever by simply persisting at some magical low-level intensity. Instead, it cheats death by repeatedly returning to its polyp form-- one of the earliest stages of jellyfish development. The behavior was first described in a 1996 study titled "Reversing the Life Cycle," with the paper's authors noting that the behavior was tantamount to "achieving potential immortality." The immortal jellyfish can still die, of course, in the exciting and violent ways the ocean has to offer (mainly getting eaten by strange fish and relatable dugongs). But when faced with old age, sickness, or life-threatening trauma, it will simply rejuvenate, aging backwards over a period of a few days.

Add the understated immortality of Turritopsis dohrnii to this list of achievements and you've got at the very least an impressive Powers and Abilities section for a supervillain's Wikipedia page. If the bestiaries had known about jellyfish, they probably would have just given up trying to extricate God's meaning from the natural world and just worshipped the jellies instead.

Turritopsis dohrnii hasn't been the subject of a Big Pharma-sponsored jellyfish-hunt with black ops divers tracking it down to reverse-engineer its genetic secrets. This is thanks, at least in part, to the difficulty of breeding the species, which requires constant nannying and care. (For more on this topic and the Japanese marine biologist who cultivates the species-- he's known as Mr. Immortal Jellyfish Man-- you should read this fantastic New York Times piece.) It's an animal that's difficult to exploit because it's just so demanding-- like a kidnapped teen in a '90s comedy who outwits their captors simply by being unthinkingly spoiled.