CLOSE
Original image

6 Horrifying Parasites

Original image

By Chris Connolly

These life-sucking go-getters have managed to carve out some of the most ingenious survival strategies in the world. By some estimates, parasites outnumber free-living species nearly four to one. So show some respect. After all, mooching isn't as easy as it looks.

1. Cymothoa exigua: Biting Your Tongue, So You Don't Have To

When fish mommies want to strike fear in the hearts of their misbehaving fish babies, we suspect they draw on the chilling animal savagery of the Cymothoa exigua. As a youngster, this nasty little parasitic crustacean begins a life of terror by fighting its way through the gills of its fish host of choice, the snapper. Once there, it attaches itself to the fish's tongue and begins feeding on the rich blood pumping through the artery underneath. As the parasite grows, it drinks more blood and eventually causes the tongue to atrophy and disintegrate. But does the Cymothoa mouth-squatter leave its fishy friend tongueless? Of course not. It does what any crafty parasite would do and replaces the old tongue with its own body. The fish is actually able to use the parasite just like a normal tongue, only it has to share all the food with its new friend. Yes, the whole foster-tongue thing seems like a pretty nice gesture on the part of ol' Cymothoa—until you remember there was nothing wrong with the fish's old tongue in the first place.

2. Screwworms: Causing Problems Right out of the Hatch

Plenty more (disgusting) creatures after the jump...

worms.jpgThe screwworm isn't really a worm at all; it's a type of fly. But if living under a false name were the worst of the screwworm's misdeeds, you can be sure it wouldn't appear in this story. No, this parasite's rap sheet is about to get much, much more disturbing. To find its host, an adult female screwworm seeks out exposed flesh on an animal (usually some sort of livestock, but an injured soldier or a human baby isn't out of the question) in search of a place to lay her eggs. She prefers wounds, but may also settle on using the eyes, nostrils, or anus of her victim to construct a nursery. Next, the 200-or-so eggs hatch, and the larvae start burrowing into their host's flesh. Once they're situated in their cozy little meat tunnels, the infant flies continue to feed and grow. The bigger they get, the more they have to eat. Eventually, this creates a whole lot of festering and oozing on the host, which attracts more flies, which lay more eggs, which do more feeding and burrowing. It's a brutal onslaught, and a swift one. Screwworm larvae are reportedly capable of consuming an entire sheep or dog from the inside out in five to seven days.

3. Sacculina carcini: Reasons You Shouldn't Pick up a Hitchhiker

Sacculinacarciniweb.jpgIf you ever have a choice between being possessed by the devil and being possessed by a Sacculina carcini, opt for the devil—no contest. A female sacculina begins life as a tiny free-floating slug in the sea, drifting around until she encounters a crab. When that fateful day arrives, she finds a chink in the crab's armor (usually an elbow or leg joint) and thrusts a kind of hollow dagger into its body. After that, she (how to put this?) "injects" herself into the crab, sluicing through the dagger and leaving behind a husk. Once inside, the jellylike sacculina starts to take over. She grows "roots" that extend to every part of the crab's body—wrapping around its eyestalks and deep into its legs and arms. The female feeds and grows until eventually she pops out the top of the crab, and from this knobby protrusion, she will steer the Good Ship Unlucky Crab for the rest of their commingled life. Packed full of parasite, the crab will forgo its own needs to serve those of its master. It won't molt, grow reproductive organs, or attempt to reproduce. It won't even regrow appendages, as healthy crabs can. Rather than waste the nutrients on itself, a host crab will hobble along and continue to look for food with which to feed its parasite master.

4. Filarial Worms: Proof You Need Thicker Skin

lf2.jpgFilarial worms are the nasty little suckers you can thank for lymphatic filariasis, which, according to the Pacific Program to Eliminate Lymphatic Filariasis, is the second-leading cause of permanent and long-term disability in the world. (Mental illness is No. 1.) Filarial worms are round, thread-like parasites that travel from human to human via that harbinger of disease transmission, the mosquito. How do they make the leap of host? In an interesting (if scary) example of parasite ingenuity, filarial worm embryos living underneath the skin can sense the onset of night, which is their cue to head upward to the skin's surface in order to increase their chances of being picked up by a passing 'skeeter. Should they get sucked up, they grow into larvae within the mosquito's muscle fibers and then get themselves injected into new hosts. Once they've returned to a human home, they open up a franchise in the family business—Wreaking Havoc. Filaria often lodge in the body's lymphatic system, where they can inflict any number of torturous symptoms, not the least of which involves carting your genitals off to the elephantiasis clinic in a wheelbarrow.

5. Guinea Worms: Exposing Parts Nobody Wants to See

guinea-worm.jpgWhere there are guinea worms, there is Guinea Worm Disease—and that's usually in Africa. When a human consumes water contaminated with guinea worms, the little buggers infiltrate their host's intestinal walls and commence mating. After conception, the males die off, and the females hang around for about a year, growing and eating. Eventually, these slender ladies get bored and decide they need to lay some eggs. To do so, they make their way down the body to the lower extremities, where they bore a small hole through the skin. The resulting lesion begins to fester and burn, which usually leads the host to plunge his or her foot into a soothing bucket of water. (Of course, in areas where an entire village shares a single water source, this helps spread the infection.) Unfortunately for the sufferer, the water doesn't solve the problem of having a three-foot female worm dangling its genitalia out of your foot. And to complicate matters, if you yank on that sucker, it'll break apart and could cause a fatal infection. So how do you rid yourself of the not-so-little hitchhiker? You go see a doctor, who—over the course of three or four weeks—will kindly wind the worm around a stick, inch by agonizing inch. Not the most pleasant method, but certainly a proven one. This cure for a guinea worm infection has been around so long, some believe it's where we get the snakes-around-a-staff symbol for medicine.

6. Leucochloridium paradoxum: Parasite for Sore Eyes

mimicry_2.jpgPrepare to be dazzled. This parasite's got a life cycle more mind-bending and chilling than an M. Night Shyamalan film. Leucochloridium paradoxum are a type of fluke (a.k.a., parasitic flatworm) that prey on birds—a fascinating turn of events considering they begin their lives as eggs in bird droppings. Thus, the problem facing baby Leucochloridium paradoxum is, "How do I get myself back into one of those feathery things?" Taking a page from Greek history, the infant flatworms rely on Trojan trickery. First, they hang out in the droppings until a snail happens along and eats the bird dung. Then they initiate their devious plan of action by taking up residence in the snail's eyestalks. (Sure, it sounds slimy and gross to us, but after a childhood spent living in bird feces, it's a step up.) As they mature, the flukes become visible through the snail's translucent skin. And that's when things really get interesting. To a bird, this fluke-filled eyestalk looks like a caterpillar. So the bird devours the stalk and ends up with a bellyful of Leucochloridium paradoxum that will, of course, lay eggs and begin the cycle again. Meanwhile, the snail shakes its head, shops for an eye patch, and vows never to eat feces again.

--
Ed. note: We thought the parasites were so horrifying that we decided to get the very talented Randy Riggs to film a B-horror movie around the subject. Here's the trailer for what he came up with.

This article was pulled from an earlier edition of mental_floss. Make our editors happy and subscribe today.

Original image
iStock
arrow
Big Questions
Why Don't We Eat Turkey Tails?
Original image
iStock

Turkey sandwiches. Turkey soup. Roasted turkey. This year, Americans will consume roughly 245 million birds, with 46 million being prepared and presented on Thanksgiving. What we don’t eat will be repurposed into leftovers.

But there’s one part of the turkey that virtually no family will have on their table: the tail.

Despite our country’s obsession with fattening, dissecting, and searing turkeys, we almost inevitably pass up the fat-infused rear portion. According to Michael Carolan, professor of sociology and associate dean for research at the College for Liberal Arts at Colorado State University, that may have something to do with how Americans have traditionally perceived turkeys. Consumption was rare prior to World War II. When the birds were readily available, there was no demand for the tail because it had never been offered in the first place.

"Tails did and do not fit into what has become our culinary fascination with white meat," Carolan tells Mental Floss. "But also from a marketing [and] processor standpoint, if the consumer was just going to throw the tail away, or will not miss it if it was omitted, [suppliers] saw an opportunity to make additional money."

Indeed, the fact that Americans didn't have a taste for tail didn't prevent the poultry industry from moving on. Tails were being routed to Pacific Island consumers in the 1950s. Rich in protein and fat—a turkey tail is really a gland that produces oil used for grooming—suppliers were able to make use of the unwanted portion. And once consumers were exposed to it, they couldn't get enough.

“By 2007,” according to Carolan, “the average Samoan was consuming more than 44 pounds of turkey tails every year.” Perhaps not coincidentally, Samoans also have alarmingly high obesity rates of 75 percent. In an effort to stave off contributing factors, importing tails to the Islands was banned from 2007 until 2013, when it was argued that doing so violated World Trade Organization rules.

With tradition going hand-in-hand with commerce, poultry suppliers don’t really have a reason to try and change domestic consumer appetites for the tails. In preparing his research into the missing treat, Carolan says he had to search high and low before finally finding a source of tails at a Whole Foods that was about to discard them. "[You] can't expect the food to be accepted if people can't even find the piece!"

Unless the meat industry mounts a major campaign to shift American tastes, Thanksgiving will once again be filled with turkeys missing one of their juicier body parts.

Have you got a Big Question you'd like us to answer? If so, let us know by emailing us at bigquestions@mentalfloss.com.

arrow
Animals
10 Juicy Facts About Sea Apples

They're both gorgeous and grotesque. Sea apples, a type of marine invertebrate, have dazzling purple, yellow, and blue color schemes streaking across their bodies. But some of their habits are rather R-rated. Here’s what you should know about these weird little creatures.

1. THEY’RE SEA CUCUMBERS.

The world’s oceans are home to more than 1200 species of sea cucumber. Like sand dollars and starfish, sea cucumbers are echinoderms: brainless, spineless marine animals with skin-covered shells and a complex network of internal hydraulics that enables them to get around. Sea cucumbers can thrive in a range of oceanic habitats, from Arctic depths to tropical reefs. They're a fascinating group with colorful popular names, like the “burnt hot dog sea cucumber” (Holothuria edulis) and the sea pig (Scotoplanes globosa), a scavenger that’s been described as a “living vacuum cleaner.”

2. THEY'RE NATIVE TO THE WESTERN PACIFIC OCEAN.

Sea apples have oval-shaped bodies and belong to the genus Pseudocolochirus and genus Paracacumaria. The animals are indigenous to the western Pacific, where they can be found shuffling across the ocean floor in shallow, coastal waters. Many different types are kept in captivity, but two species, Pseudocolochirus violaceus and Pseudocolochirus axiologus, have proven especially popular with aquarium hobbyists. Both species reside along the coastlines of Australia and Southeast Asia.

3. THEY EAT WITH MUCUS-COVERED TENTACLES.

Sea cucumbers, the ocean's sanitation crew, eat by swallowing plankton, algae, and sandy detritus at one end of their bodies and then expelling clean, fresh sand out their other end. Sea apples use a different technique. A ring of mucus-covered tentacles around a sea apple's mouth snares floating bits of food, popping each bit into its mouth one at a time. In the process, the tentacles are covered with a fresh coat of sticky mucus, and the whole cycle repeats.

4. THEY’RE ACTIVE AT NIGHT.

Sea apples' waving appendages can look delicious to predatory fish, so the echinoderms minimize the risk of attracting unwanted attention by doing most of their feeding at night. When those tentacles aren’t in use, they’re retracted into the body.

5. THE MOVE ON TUBULAR FEET.

The rows of yellow protuberances running along the sides of this specimen are its feet. They allow sea apples to latch onto rocks and other hard surfaces while feeding. And if one of these feet gets severed, it can grow back.

6. SOME FISH HANG OUT IN SEA APPLES' BUTTS.

Sea apples are poisonous, but a few marine freeloaders capitalize on this very quality. Some small fish have evolved to live inside the invertebrates' digestive tracts, mooching off the sea apples' meals and using their bodies for shelter. In a gross twist of evolution, fish gain entry through the back door, an orifice called the cloaca. In addition expelling waste, the cloaca absorbs fresh oxygen, meaning that sea apples/cucumbers essentially breathe through their anuses.

7. WHEN THREATENED, SEA APPLES CAN EXPAND.

Most full-grown adult sea apples are around 3 to 8 inches long, but they can make themselves look twice as big if they need to escape a threat. By pulling extra water into their bodies, some can grow to the size of a volleyball, according to Advanced Aquarist. After puffing up, they can float on the current and away from danger. Some aquarists might mistake the robust display as a sign of optimum health, but it's usually a reaction to stress.

8. THEY CAN EXPEL THEIR OWN GUTS.

Sea apples use their vibrant appearance to broadcast that they’re packing a dangerous toxin. But to really scare off predators, they puke up some of their own innards. When an attacker gets too close, sea apples can expel various organs through their orifices, and some simultaneously unleash a cloud of the poison holothurin. In an aquarium, the holothurin doesn’t disperse as widely as it would in the sea, and it's been known to wipe out entire fish tanks.

9. SEA APPLES LAY TOXIC EGGS.

These invertebrates reproduce sexually; females release eggs that are later fertilized by clouds of sperm emitted by the males. As many saltwater aquarium keepers know all too well, sea apple eggs are not suitable fish snacks—because they’re poisonous. Scientists have observed that, in Pseudocolochirus violaceus at least, the eggs develop into small, barrel-shaped larvae within two weeks of fertilization.

10. THEY'RE NOT EASILY CONFUSED WITH THIS TREE SPECIES.

Syzgium grande is a coastal tree native to Southeast Asia whose informal name is "sea apple." When fully grown, they can stand more than 140 feet tall. Once a year, it produces attractive clusters of fuzzy white flowers and round green fruits, perhaps prompting its comparison to an apple tree.

SECTIONS

arrow
LIVE SMARTER
More from mental floss studios