Wolverine may be a fictional superhero, bearing retractable claws that can tear his enemies to shreds, but he’s got a real-life counterpart: the Spanish ribbed newt. 

Only, this amphibian is no mutant — its superpowers are entirely natural, a defense mechanism that allows it to use its own rib bones to protect itself against predators. A natural historian discovered the newt’s abilities in 1879, but researchers have only recently learned exactly how the Spanish ribbed newt does it, using modern photographic and X-ray technology.

As it turns out, this incredible little creature has the ability to swing its ribs forward, increasing the ribs' angle to the spine up to 50 degrees when it perceives a threat. As it thrusts its ribs forward, it keeps the rest of its body still, stretching the skin to the point of piercing it.

The tips of the newt’s ribs stick out like spines. If that weren’t already dangerous enough, the newt has another trick up its sleeve.

"When teased or attacked by a predator, [the newt] secretes a poisonous milky substance onto the body surface. The combination of the poisonous secretion and the ribs as 'stinging' tools is highly effective," zoologist Egon Heist of the University of Vienna in Austria told BBC News.

Despite repeatedly puncturing its own body with its ribs, the newt does not suffer any major ill effects. Amphibians are known for a remarkable ability to repair their skin after injuries. Heiss, who plans to analyze the poison, says the newt seems immune to it.

"Anyway, if this newt can avoid being eaten in some cases, this surely has a positive influence."