Luke Cage

Science Behind the Fiction: Luke Cage's indestructible skin and super strength

Contributed by
Jul 11, 2018

Marvel Studios has been absolutely crushing it, like a Hulk falling from the heavens, for the past decade. Partnering with Netflix, Marvel Studios has produced a slate of shows, including Daredevil, Jessica Jones, Iron Fist, and Luke Cage, that allow the viewer to participate in a slower, more intimate viewing experience.

The second season of Luke Cage recently dropped on Netflix, returning us to Harlem and the ongoing adventures of Carl Lucas, aka Luke Cage, aka Power Man.

Luke Cage first entered the scene in Hero for Hire #1 (1972). Within its pages, we were introduced to Carl Lucas, a New York resident with a complicated past. Framed for a crime he didn't commit, Lucas was sent to prison on drug charges and involved in cell regeneration experiments. Left unattended in a bath of electrically charged organic compounds and at the mercy of a homicidal prison guard with an ax to grind, Lucas emerged with incredible strength and impenetrable skin.

What makes Luke Cage so endearing is his humanity. He seems, despite the fantastical dressings of his daily goings-on, like a regular guy set to task against incredible obstacles. Which forces us to wonder, how might you or I become a hero for hire?

Incredible strength

To the average person, there seems to be a natural limit to endeavors of strength, even if that strength runs the spectrum from your average couch potato to Game of Thrones actor Hafþór Júlíus Björnsson (Gregor Clegane, aka The Mountain). But, according to some studies, there's reason to believe that our actual limit lies beyond what we're ordinarily capable of. Feats of so-called "hysterical strength," tales of individuals lifting cars to save loved ones, showcase ordinary people accomplishing feats beyond the normal limit of human ability.

The data suggests that our brains set limits in order to protect us from injuring ourselves — but under extraordinary circumstances, we're capable of so much more.

The trouble is, researchers are unable to design experiments allowing for unusual scenarios that might uncover the actual limits of our abilities. Such an experiment would run afoul of just about every code of ethics there is and, even with that aside, any intentional experiment would be unlikely to set off the necessary emotional reactions to get measurable data.

As a result, examples of hysterical strength are anecdotal. Even so, there is some evidence to suggest that the limits of human strength lie somewhere beyond what we see in everyday life.

E. Paul Zehr, a professor of neuroscience and kinesiology at the University of British Columbia says, "Our brains are always trying to make sure we don't get pushed too far to where we actually damage something. If you actually used all the possible force or all the possible energy you could to complete exhaustion, you'd wind up getting into a situation where you might die." Which is to say that the average person is always operating at a percentage lower than their actual total strength. It might only take an unusual set of circumstances to unlock the heretofore unseen ability.

Knowing that human ability is somewhere beyond what we see on a day to day basis and that the limits of strength, when considering high performing athletes, are considerably higher than the average person, it's not unreasonable to believe that someone like Carl Lucas, under the influence of science, might accomplish feats of strength that would seem incredible to you and me.

Impenetrable skin

Incredible strength goes a long way toward accomplishing the feats Power Man needs to in order to keep crime at bay in Harlem, but it would be worth little if he was out of the game the first time someone shot at him. And people shoot at him a lot.

That's where Cage's bulletproof skin comes into play. Cage has survived walls of bullets, explosions, collapsing buildings, and grenades going off in his hand — among a slew of other high-impact traumas — and walked away more or less unscathed.

Every kid learns pretty early on, when they take their first tumble and skin their knees, that our skin is less than impenetrable.

That isn't to say our skin isn't incredible in its own right. The skin is the largest single organ in (or on) your body. It accounts, on average, for roughly nine pounds of your weight and spans roughly twenty-one square feet. It's important for regulating body temperature and has an array of receptor cells without which you'd be incapable of adequately interacting with the world around you.

It might be easy to take your skin for granted, what with the blemishes and itchy reactions to bug bites and allergens, but it keeps your insides intact and the bad stuff at bay.

It even has some pretty cool superpowers of its own, like the ability to stretch without tearing and regenerate relatively quickly. On average, skin regenerates every 27 days.

As amazing as human skin is, it's nowhere near the coolest skin in the animal kingdom.

Crocodilians (a group of reptiles that includes crocodiles, gharials, alligators, and caimans) have super-tough skin composed of keratin and plates that come together to form a kind of armor. This isn't all that surprising considering they are ancient killing machines honed over millennia of evolution. What is surprising is how sensitive they are to external stimuli. It would stand to reason that with such fierce armor would come a correlating decrease in sensitivity, like how you lose dexterity and feeling when wearing a thick glove, but a study published in the Journal of Experimental Biology reveals a complex array of touch sensors hidden in crocs' faces.

"We didn't expect these spots to be so sensitive because the animals are so heavily armored," said Duncan Leitch, the graduate student responsible for the study.

Sperm whales hold the record for the world's thickest skin. Their ability to withstand criticism notwithstanding, they can certainly stand up to other large predators of the deep. A sperm whale's skin is approximately 14 inches thick. That's necessary when doing spectacular undersea battle with colossal squid. The bodies of sperm whales are often pocked with scars leftover from deep-sea melees. Crocodilians use tough, armored scales and sensitivity to their surroundings to avoid being injured at all. Sperm whales, meanwhile, use the thickness of their skin to prevent injury to the more fragile bits underneath. African spiny mice use a completely different strategy, one that is as incredible as it is terrifying.

When compared to other mice, the skin of the African spiny mouse is up to 20 times weaker than its peers. When faced with a predator, this tiny mammal will shed its skin like the crusty layer of a burnt marshmallow in order to escape.

According to a study in the journal Nature, some mice lost up to 60 percent of their skin in an encounter.

Ordinarily, that's the sort of injury that would spell certain death, but in the case of the African spiny, it's just another day. These little critters have the amazing ability to regrow their skin in a matter of days and with seemingly no ill effects. Not only does the skin grow back good as new, but it doesn't scar. They'll even grow fur over the damaged spot. Once the regenerative cycle is complete, its as if no injury took place at all.

As exciting as Marvel's Luke Cage is, it could have been a whole lot more terrifying if they'd taken a page or two from the animal kingdom.

Season 2 of Luke Cage is now available on Netflix.