Meet the lamprey: the nightmarish creature that could hold the secrets to spinal cord regeneration.

You could be forgiven for never having heard of the lamprey, an obscure lineage of fish that shared a common ancestor with humans approximately 550 million years ago.

In fact, the only prominent example of this strange creature featuring in popular culture is their alleged role in the death of King Henry I, who, legend has it, met a gruesome demise after gorging himself on a “surfeit of lampreys.” Disappointingly, historians now believe he simply died of food poisoning.

The ancient creature looks deceptively like an eel, though depictions often focus on its alarming circular mouth: a flat disk covered in menacing rings of teeth that the lamprey uses to latch onto their unfortunate prey and suck their blood. Primitive and somewhat creepy though they may appear, lampreys possess one nifty talent that has inspired great interest among scientists: the ability to regenerate their spinal cord.

In recent weeks this humble fish has been thrust into the spotlight once again, as researchers at the Marine Biology laboratory in Chicago have shown that the lamprey can spontaneously regenerate this critical structure not just once, as previously thought, but twice. “We’ve determined that central nervous system (CNS) regeneration in lampreys…