This Oceanic ‘Nightmare’ Suffocates Foes With Clouds of Slime

“Ahhh!” cries the hagfish as it bombards its captors with slime, “smiles … my only weakness! Also, admittedly, I’m not so good at surviving out of water.”

The most loveable ghost ever has to be Slimer, mostly because I don’t buy Casper’s overdone friendliness shtick for a second. In Ghostbusters, Slimer introduces himself to Bill Murray with a hug, leaving him with a coating of ectoplasm. Few people realize that this harmless gesture is how ghosts show affection.

Bill was all bent out of shape about the whole thing, but it could have been much worse for him. He could have tangled with a real-life slimer: the hagfish, a bizarre, eel-like critter that asphyxiates the fish and sharks foolish enough to attack it by clogging up their gills with massive releases of goo. But this is no simple snot. It’s a deceptively complex substance that could one day gift us the supermaterial of our dreams.

The hagfish cruises around deep ocean bottoms, feeding primarily on polychaete worms–save for the ferocious 10-foot bobbit worm, which luckily for the hagfish inhabits shallow waters. Every once in a while, though, it takes part in one of the sea floor’s most remarkable happenings: the arrival of a whale carcass (an event known somewhat epically as a whale fall).

Whale hides are quite tough, and the hagfish has nowhere near the bite force of a shark. But hagfish have been around for at least 300 million years, and they didn’t spend all that time not developing sweet adaptations for scavenging in the deep.

When they are lucky enough to come upon a whale fall, they “grab onto it with their teeth, which are sort of like a circular set of saw blades,” said Carol Bucking, a biologist at Toronto’s York University. “And they use this to latch on to the skin, and then they twist their body to bore a hole into the carcass. Then they live inside the carcass and they essentially eat it from the inside out.”

This picture of hagfish chompers is remarkably similar to the movie poster for Tremors, starring Kevin Bacon. Therefore, the hagfish has no degrees of separation from Kevin Bacon, which is more than a lot of people can say.

If they’re having trouble ripping off flesh, they can actually tie themselves in knots, then use that as leverage to excavate meat. Hagfish are afforded such flexibility because while they have a partial skull, they have no spine to speak of (accordingly, scientists have a hell of a time classifying this ancient species). And though they may look weak and squishy, hagfish are actually burly gnawing machines. “If you try to pick one up and hold onto it,” said Bucking, “it’s essentially like holding onto a boa constrictor. It’s almost impossible to sort of dictate what it does, because it’s a very strong, enormous, nightmare of a creature.”

Once the hagfish has muscled its way inside a carcass, simply swallowing its food is not enough: They’ve actually evolved a way to pull nourishment through their skin, utilizing the same kind of nutrient “transporters,” as they’re known, that you would find in your guts. So, really, they’re an inside-out intestine with another intestine inside, like Russian nesting dolls of the deep. And as the decaying whale’s proteins break down into amino acids, the hagfish happily soaks them right up into its bloodstream.

Hagfish are particularly drawn to good lighting, so the rays can play off their skin all romantic-like.

But first the hagfish has to find its quarry in the total blackness of the deep. For that, they rely not on their rudimentary eyespots, which are almost totally worthless, but on their extremely keen sense of smell, sniffing out the slightest of odors with the barbels around their mouths. Indeed, their forebrain, which processes smells, is highly enlarged to handle all of this information.

Without any real eyesight, though, and with its face buried in rotting whale, the hagfish is an easy target for predators. But if you take a bite out of this critter, you do so at your own peril. For the hagfish makes the world’s most disgusting, most dangerous Jell-O–except for the apricot kind. Seriously, who buys the apricot kind?

Slime and Punishment

Up and down the length of the hagfish’s body are some 150 separate slime glands. When a predator like a shark bites down on a hagfish, the tiny glands near the attacker’s strike instantaneously eject the goo. As soon as this hits water, it balloons into a huge gelatinous cloud, which biologist Douglas Fudge of Ontario’s University of Guelph reckons acts to clog up the attacker’s gills.

He’s fairly confident of this because he, well, did some experiments with disembodied fish heads. Fudge first measured water flow over the gills in a normal state, then applied hagfish slime. “If this stuff evolved to clog up gills,” he said, “then you’d expect it to really reduce the flow over the gills, and that’s exactly what it did. It increased the resistance of the gills by something like 200-fold.”

While no one has yet been able to pursue a predator choking on a mouthful of hagfish slime to see if it indeed suffocated to death–quite understandably, they tend to rapidly retreat, as demonstrated somewhat hilariously in the video above–Fudge thinks that if the victim isn’t able to somehow dislodge the goo from its gills, it will perish.

How, then, does the hagfish keep from suffocating itself? They have “beautiful, almost balloon-shaped gills, and so that really restricts anything getting into them,” said Bucking. The hagfish pumps water through a series of small holes into pouches, where “there’s all these channels and chambers that spread the water out and put it in contact with blood so they can exchange oxygen.” It can also clear the slime off its body with the same technique it uses to feed, tying itself in a knot and passing itself through it.

Hagfish are extremely flexible because they lack a backbone, going so far as to tie themselves in knots in dogged pursuit of Boy Scout badges.

Those are no ordinary gills, because this is no ordinary snot. Inside each slime gland are two kinds of cells. One produces a whole lot of mucus. The other–the really interesting one for materials scientists–produces entirely remarkable threads. These are 6 inches long, intricately coiled into a single cell that’s just four-thousandths of an inch long. That, quite frankly, is insane. As a loose metaphor, it’s like packing 10,000 years’ worth of clothes into one suitcase that you’ll then, uh, break open and throw at something that’s attacking you.

When the slime glands are emptied, the fibers (25,000 in just four cups of goo) mix with the mucus and unravel in a fraction of a second. “What we think is going on is that there’s a glue that we haven’t yet identified, but we have good evidence for, that holds the fiber bundles together, and it’s a seawater-soluble glue,” said Fudge. When the glue dissolves, the fibers release like springs, providing the energy to greatly inflate the cloud. The fibers further unravel and expand the mucus as the hagfish thrashes about in the predator’s jaws.

Read more at Wired Science