11 Fascinating Facts About the Frilled Shark

Sometimes called a “living fossil” because it has changed so little since prehistoric times, the eel-like frilled shark—which is rarely seen by humans—has been in the news this week after a snake-like one was found off the coast of Portugal. Here’s a quick primer.

1. IT’S NAMED FOR ITS GILLS.

Its scientific name is Chlamydoselachus anguineus, but this creature’s common name comes from its gills: Unlike all other sharks, which have separate gills, C. anguineus’ first pair of gills go all the way across its throat; each pair is lined at the edges with red “fringe.”

2. IT WAS DISCOVERED IN THE 19TH CENTURY.

The sharks were first scientifically described by German ichthyologist Ludwig H.P. Döderlein, who taught at Tokyo University from 1879 to 1881 and brought two specimens captured in Tokyo Bay when he returned to Vienna. His paper describing the sharks was lost, however, so the first description comes from Samuel Garman in the 1884 edition of the Bulletin of Essex Institute. In the remarks after the description, Garman noted that

Such an animal as that described is very likely to unsettle disbelief in what is popularly called the “sea serpent.” Though it could hardly on examination be taken for anything but a shark, its appearance in the forward portion of the body, particularly in the head, brings vividly to mind the triangular heads, deep-cleft mouths, and fierce looks of many of our most dreaded snakes. In view of the possible discoveries of the future, the fact of the existence of such creatures, so recently undiscovered, certainly calls for a suspension of judgment in regard to the non-existence of that oft-appearing but elusive creature, the serpent-like monster of the oceans.

The frilled shark’s species name, anguineus, is Latin for “consisting of snakes” or “snaky.”

Biologist David A. Ebert, director of the Pacific Shark Research Center, described a second frilled shark species—Chlamydoselachus africana, which lives off the coast of Africa and is about half as long as its predecessor—in 2009.

3. IT’S GOT INSANE TEETH.

The frilled shark’s mouth is just as terrifying as the maw of a great white: It’s lined with 25 rows of backward-facing, trident-shaped teeth—300 in all. “The teeth are constructed for grasping and from their peculiar shape and sharpness it would seem as if nothing that once came within their reach could escape them,” Garman wrote. “Even in the dead specimen the formidable three-pronged teeth make the mouth a troublesome one to explore.” 

Ebert can testify to that fact. “I can tell you from snagging my fingers on the teeth, you can only back out one way and that’s in toward the mouth and then out,” he told WIRED. “It didn’t feel good, I can tell you that.” The shark uses the bright white teeth, which sharply contrast against its brown body, to lure in prey: “By the time [the prey] realize, Oh, that’s the teeth of a shark, they’re too close and the shark is able to ambush them at that point,” Ebert said. “It’s almost like when you drive out of a parking lot exit and they have the spikes sticking out that say, ‘Do not back up.’ That’s kind of what happens when these things catch prey items.”

And as if its teeth weren’t freaky enough, the frilled shark has spines, called dermal denticles, lining its mouth. So if you happen to see one of these anywhere, it’s better to look and not touch.

4. IT “HOVERS” IN THE WATER...

Scientists once believed that the frilled shark wriggled through the water like an eel. But according to the ReefQuest Centre for Shark Research, “its body cavity is elongate and packed with a huge liver perfused with low-density oils and hydrocarbons, making the shark almost neutrally buoyant at depth.”

5. … AND IT MAY STRIKE AT ITS PREY LIKE A SNAKE.

No one has ever observed the frilled shark hunting, but scientists believe that it uses its posterior fins as propulsive surfaces to launch itself at its prey. Its long jaws, which terminate at the back of its head, may allow the animal to gape extra wide and take in prey half as long as its body. Analysis of the stomach contents of captured specimens has revealed that the frilled shark’s diet is 61 percent cephalopod, 11 percent teleost fishes, and, occasionally, other sharks.

6. IT’S FOUND ALL OVER THE WORLD—BUT YOU PROBABLY WON’T SEE IT.

The Food and Agriculture Organization of the United Nations notes that the frilled shark is “wide-ranging but spottily distributed”; you can see where the shark is found on the map above. It typically resides in depths between 390 and 4200 feet, so people rarely see these sharks unless they venture to the surface, which isn’t unheard of (as you’ll see below).

7. FEMALES ARE BIGGER THAN MALES.

On average, males range from 3.2 to 3.6 feet and females from 4.4 to 4.9 feet; the maximum these sharks can reach is 6.4 feet.

8. THEIR GESTATION PERIOD MAY BE 3.5 YEARS LONG.

A study of frilled sharks in Japan revealed that the animals breed year-round; litters typically consist of six pups, which emerge from eggs while still in the mother’s uterus and are then born live. Scientists think the shark may have the longest gestation period ever: Frilled sharks could gestate for as long as 42 months, nearly twice as long as African elephants carry their young. Scientists theorize that the extreme length has something to do with the shark’s cold deep sea habitat.

9. IT WASN’T SEEN IN ITS NATURAL HABITAT UNTIL 2004.

NOAA scientists exploring the “Latitude 31-30 Transect” in the Atlantic Ocean captured a video of a frilled shark “swimming over sea bottom that was covered with tiny sand dunes” during a submersible dive. “This species has been, on rare occasion, caught or taken in bottom trawls,” the site notes. “To the knowledge of everyone on board, however, this was the first time anyone had ever seen the rare species in its natural habitat.”

10. ONE WAS CAPTURED IN JAPAN IN 2007.

In January 2007, a Japanese fisherman spotted a strange, eel-like creature with a mouth full of sharp teeth near the surface; he alerted the staff of the Awashima Marine Park in Shizuoka, who captured the animal and transferred it to a seawater pool, where they filmed it. “We think it may have come close to the surface because it was sick, or else it was weakened because it was in shallow waters,” a park official said. “We believe moving pictures of a live specimen are extremely rare. They live between 600 and 1000 meters under the water, which is deeper than humans can go.” The shark, a female, died a few hours after its capture.

11. IT CALLS ANOTHER FREAKY SHARK ITS COUSIN.

The frilled shark might have rows upon rows of gnarly teeth, but its cousin, the goblin shark, can thrust its jaw out of its face. Which is more terrifying?

The Tower of London Welcomes New Baby Ravens for the First Time in 30 Years

Some of the baby ravens born at the Tower of London
Some of the baby ravens born at the Tower of London
Tower of London Twitter (screenshot)

There are some new residents at the Tower of London. They're only about 11 inches tall, are very noisy, and eat rats for breakfast, lunch, and dinner. Fortunately, they're also adorable—not to mention protected by legend.

On May 17, the Tower of London announced that their breeding pair of ravens, Huginn and Muninn, had welcomed four healthy chicks, the first born at the Tower since 1989. The ravens are part of an unkindness that's been located at the Tower for centuries as a sort of protective asset. According to legend, the Tower must always have ravens, or both the Tower and the kingdom will fall. It's not exactly clear when the legend began, but according to the Tower, Charles II decreed there must always be six ravens present.

Huginn and Muninn are newer additions, having arrived at the Tower in late 2018, and they weren't expected to breed this spring. So it was a surprise in mid-April when the devoted Tower Ravenmaster, Yeoman Warder Chris Skaife, noticed something exciting going on. "My suspicions were first piqued that we might have a chance of baby chicks when the parents built a huge nest suddenly overnight and then almost immediately the female bird started to sit on it," Skaife said in a Tower press release. On April 23, Skaife noticed the birds flying to the nest with food, but it was only this week he was able to get close enough to see the four healthy chicks. The sight delighted him: "Having worked with the ravens here at the Tower for the last 13 years and getting to know each of them, I feel like a proud father!"

The chicks have grown quickly, already quadrupling in size since they were born, and eat a diet of quail, rats, and mice the Ravenmaster provides. The raven parents have an egalitarian feeding arrangement: Huginn, the male, preps the food and passes it to Muninn, the female, who feeds it to her tiny chicks.

The plan is for one of the chicks to stay at the Tower and join the rest of the ravens there. "As the ravens started to hatch on the 23 April, St. George’s Day, the raven that will be staying at the Tower will be called George or Georgina in honor of the occasion," the Tower explained in a press release. According to The Telegraph, the breeding program at the Tower kicked off in response to a decline in the number of legal raven breeders in the UK.

The last raven chick born at the Tower was Ronald Raven, born May 1, 1989. In his 2018 book, The Ravenmaster: My Life with the Ravens at the Tower of London, Skaife wrote that "a baby raven looks a bit like a grotesque miniature gargoyle, but then you see them grow and develop ... It really is wonderful."

The baby ravens born at the Tower of London in 2019
The baby ravens born at the Tower of London in 2019 making some noise
Yeoman Warder Chris Skaife

Dozens of Donkeys, Mini-Donkeys, and Baby Donkeys Are Looking for New Homes

iStock.com/huggy1
iStock.com/huggy1

Cats and dogs aren't the only rescue animals that need permanent homes. At the Humane Society of North Texas (HSNT), there are over 60 donkeys, miniature donkeys, baby donkeys, and Thoroughbred horses up for adoption, the Cleburne Times-Review reports.

Many of the equines at HSNT's ranch in Joshua, Texas came from owners who had to give them up, and others were transferred from different animal rescue groups. As part of the ASPCA’s Help A Horse Home Challenge, HSNT is hosting events to help find new homes for its horses and donkeys.

Between April 26 and June 30 this year, the ASPCA is challenging equine organizations to adopt out as many animals as they can. The groups that see the biggest increases in adoptions between this year and last year's Help A Horse Home Challenge will share $150,000 in grant funding. On May 18 and June 8, HSNT is holding open houses at its ranch for anyone interested in adopting an animal. The events will also be used as opportunities to educate the public about the demands of equine ownership.

If you're not free to swing by one of HSNT's open houses, you can still apply to adopt a horse or donkey. Interested owners can fill out and submit this form [PDF] to equine@hsnt.org. And if you'd like to spend time with baby and mini-donkeys without taking one home, HSNT is also looking for volunteers.

[h/t Cleburne Times-Review]

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