12 Facts About Great White Sharks

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In 1974, Peter Benchley released Jaws, a horror novel that sold 20 million copies, spawned an iconic film—and catapulted the great white shark (Carcharodon carcharias) to infamy. Although the book brought him fame and fortune, Benchley came to rethink its negative portrayal of great whites: The author-turned-conservationist said in 1995 that if he was writing his book then, “The shark … could not be the villain; it would have to be written as the victim.” The great white is now classified as a vulnerable species. Read on to find out why the truth about Carcharodon carcharias is often stranger—and always more compelling—than the fiction that obscures it.

1. EYE-ROLLING IS A DEFENSE MECHANISM.

Many sharks protect their eyeballs with a pair of clear lid structures called nictitating membranes, which act like protective, transparent eyelids. But not great whites—they don't have the membranes. Instead, their eyeballs roll backwards into the skull reflexively when a shark bites into a thrashing victim [PDF]. This exposes the sclerotic coat, a fibrous tissue that surrounds the eye.

2. SOME REPORTS ON THEIR SIZE ARE KIND OF FISHY.

The great white is a huge fish, no question—but some claims about its maximum size are probably exaggerated. In 1870, one zoologist measured the disembodied jaws of a large adult and estimated that the whole shark must have been 36.5 feet long. But a modern reevaluation—in which the jaws were compared to those from other dead sharks—showed that the creature’s actual length was probably about 16.5 feet, and the reports of the giant shark were likely a printer’s error.

And then there's the Cojímar specimen, a great white captured and killed near Cuba in the early 1940s. Those who saw it in person said the fish was 21 feet long and weighed 7100 pounds. Since then, the claim has been disputed by fish experts who, using an available photo, calculated that the animal’s real length was also in the ballpark of 16 feet. According to biologist Jose Castro’s book The Sharks of North America, the largest great white “believed to have been measured reliably” stretched 19.6 feet long. When it comes to weight, big males have been measured weighing up to 2819 pounds while the largest female weighed 4343 pounds.

3. GREAT WHITES ARE CLOSELY RELATED TO MAKOS.

According to a 2016 paper, there are 509 species of shark divided into nine orders and 34 families. Great whites belong to the lamnidae family, which contains only four other species: the porbeagle, the salmon shark, the longfin mako, and the shortfin mako. All five sharks have conical snouts, eyes that look solid black, and lengthy gill openings. They share a couple of other things as well—including a method for trapping body heat.

4. THEY CAN STAY WARM IN FRIGID WATER.

Most shark species have no direct control over their body temperatures; they're about as hot or cold as the water they’re swimming in. But there are a handful of species—the entire lamnidae family included—that are endothermic, meaning they can consistently maintain high body temperatures even in cold water.

The great white and its relatives have their powerful muscles to thank for this talent. The muscles naturally produce heat as they contract, warming up blood in that area, which is then redistributed to other parts of the body. This allows great whites to keep their core body temperature as high as 25 degrees (Fahrenheit) warmer than the ambient water, which means they can thrive in bitterly cold places. And when muscles are kept warm, they work more efficiently, so great whites can swim faster and farther than many other sharks. On the flip side, great whites need to consume a huge amount of calories in order to keep their body temperatures up.

5. NOT ALL GREAT WHITES GO AFTER THE SAME FOODS.

Great whites have varied diets and not all individuals share the same food preferences. But in general, younger sharks mostly eat fish and squids while older, larger sharks tend to go after big targets like marine mammals. Catching small fish and biting into fatty seals are, of course, two very different tasks. This explains why juvenile white sharks have narrower teeth than adults do—the better to pierce the skins of slippery fish. Living sharks of every species possess multiple tooth rows and are constantly replacing old chompers with brand new ones. As a great white matures, its incoming teeth become broader, serrated, and triangle-shaped, allowing great white adults to tear large chunks of meat off their victims.

6. GREAT WHITES CAN GET AIRBORNE.

Fatty, calorie-rich pinnipeds like seals and sea lions are common prey for large great whites, which typically attack from below in an explosive burst. The top speed of a great white is over 20 miles per hour, and during seal hunts, they can burst completely out of the water—a feat known as breaching—which leads to the successful capture of a pinniped 40 to 55 percent of the time, depending on lighting and other variables.

7. THEY DINE ON THE WORLD’S BIGGEST FISH.

In the 1960s, a 14.7-foot great white shark was captured near an Australian whaling station and, when it was dissected, two mysterious bones were found in its stomach. They were later identified as vertebrae belonging to an adult whale shark that was estimated to be 28 feet long. These filter feeders can grow to be 40 feet long and weigh at least 7 tons; experts now think that great whites are scavenging on floating whale shark carcasses rather than hunting the fish.

8. ATTEMPTS TO PUT THEM IN CAPTIVITY HAVEN’T GONE WELL.

Certain sharks thrive in aquariums; great whites don’t. Every single great white that’s been placed in captivity has either died or been released after a brief stay. The Okinawa Aquarium, Sea World San Diego, and the now-defunct Marineland of the Pacific are among the facilities which experimented with captive white sharks at some point or other. At the Monterey Bay Aquarium, one specimen spent a record-breaking six months living in a million-gallon tank. Once she began stalking other display fish, however, she was set free. Several different factors make great whites ill-suited for captivity. To breathe, the animals must be in constant motion to push water over their gills, and aquariums don’t always offer enough space for this. Other issues include the species’ famously large appetite and its tendency to run into glass walls.

9. DESPITE MYTHS TO THE CONTRARY, GREAT WHITES CAN GET CANCER.

There’s a myth that great whites and other sharks are immune to cancer, which has had some unfortunate real-world consequences. Assertions that shark cartilage is an edible cancer cure has led to mass harvesting of the vulnerable fish.

For the record, clinical tests have shown that ingesting shark cartilage in no way treats any form of cancer. Cancer has been documented in more than 20 shark species, including the great white: The first reported instance of a tumor-plagued great white was announced in 2015.

10. THEY TRAVEL VAST DISTANCES.

The great white inhabits many of the world's oceans, but they're most often found in waters with surface temperatures from 59°F to 72°F. The species also migrates seasonally. Some travel from South Africa to Australia and back every year. Other great whites cross the Atlantic, making long treks between Cape Cod, Massachusetts and the Azores, 2300 miles away. And each winter, scores of them leave Californian waters for a point researchers have nicknamed “the white shark café.” Located halfway between Hawaii and Mexico, this region doesn’t appear to offer much in the way of food, but the sharks remain there from April to July. Data from tagged great whites tells us that the males go on rapid, deep dives multiple times per day while hanging out in this area. Nobody knows why the white shark café is such a hot destination—but it might be a place where the fish gather to breed.

11. ORCAS PREY ON THEM.

When great whites get knocked upside-down, they freeze up and exhibit “tonic immobility,” a state of semi-consciousness. There’s at least one animal that can exploit the vulnerability. On October 4, 1997, an orca was seen barreling towards a great white shark (which measured 9 to 13 feet long) near one of California’s Farallon Islands. A human onlooker filmed the orca dragging the stunned fish around on its backside. Eventually, it let go [PDF], and then ate the dead shark's liver.

Between May and the end of June 2017, the bodies of four white sharks—all missing their livers—washed onto South African beaches. All four deaths have been attributed to orcas. A great white’s liver is high in fat and loaded with nutrients, which may account for the orcas’ interest in singling it out for consumption. One of the sharks had its testicles and stomach missing as well.

12. DO THEY REALLY MISTAKE PEOPLE FOR SEALS? PERHAPS NOT.

Though shark-on-human attacks are rare, most of the time, when you do hear about an attack, a great white is behind it. Since 1580, Carcharodon carcharias has been positively identified in at least 314 unprovoked attacks on humans (80 of them fatal). No other shark species is credited with even half as many.

According to one common explanation, great whites attack humans because they mistake them for pinnipeds. The argument goes that, when viewed from below, a person on a surf board projects a seal-like silhouette.

While this is a popular idea, it leaves some critical things unexplained. First of all, great whites have proportionally large eyes by shark standards—and acute vision to boot. Also, the big fish strike seals with tremendous force at great speed; by comparison, the sharks usually move at a slow, deliberate pace when approaching people. And in the vast majority of attack incidents, a great white will deliver a single bite and then leave without consuming the victim. In fact, nearly three out of every four humans who get bitten by white sharks survive the encounter.

Biologists have proposed that when the animals bite people, they do so out of curiosity (at least, in most cases). “Great whites are curious and investigative animals. That’s what most people don’t understand,” marine biologist R. Aidan Martin told National Geographic. “When great whites bite something unfamiliar to them, whether a person or a crab pot, they’re looking for tactile evidence about what it is.”

The sharks often go out of their way to nibble on inanimate objects—such as underwater cameras—before losing interest and moving on. So maybe, when they decide to bite people, they're not looking for a snack.

You Can Now Turn Your Cat’s Adorable Face Into a Slightly Terrifying Wearable Mask

Seregraff/iStock via Getty Images
Seregraff/iStock via Getty Images

Whatever alternate dimension coughed up the digital fur technology for Cats (2019) almost definitely also blessed (or cursed) us with these eerily realistic cat masks.

shindo rinka cat mask
Shindo Rinka

According to Kotaku, all you have to do is send in a few photos of your cat, and designers will sculpt its likeness—piercing gaze, bristly fur, and all—for you to wear to Sunday brunch or, more wisely, somewhere not populated with people trying to enjoy their weekend. Part of the reason the mask looks so authentic is that it doesn’t just cover your face; it’s attached to a length of fur-covered cloth that hides your entire head. It’s not altogether unlike what Hermione Granger looked like when she accidentally transformed herself into Millicent Bulstrode’s cat with Polyjuice Potion in Harry Potter and the Chamber of Secrets.

NextShark reports that the masks are a joint venture between Japan-based companies Shindo Rinka and Workshop 91, and you can place your order by filling out a contact form on Shindo Rinka’s website. If you don’t read Japanese, you’ll have to translate the page first, and make sure you check the box next to “About ultra-real pet mask ‘My Family.’” Personalized pet merchandise of this ilk doesn’t come cheap—you’d be shelling out about $2700, not including shipping costs.

As for how your cat might react to the mask, it’s difficult to predict. Rui, the Bengal cat from Kyoto shown in the photos, doesn’t seem totally averse to the idea—but it’s been scientifically proven that cats’ facial expressions are hard for humans to read.

[h/t Kotaku]

11 Things You Might Not Know About Reindeer

Mats Lindberg/iStock via Getty Images
Mats Lindberg/iStock via Getty Images

Beyond their sled-pulling capabilities and discrimination against those with red noses, what do you really know about reindeer?

1. Reindeer and caribou are the same thing.

Historically, the Eurasian reindeer and American caribou were considered to be different species, but they are actually one and the same: Rangifer tarandus. There are two major groups of reindeer, the tundra and the woodland, which are divided according to the type of habitat the animal lives in, not their global location. The animals are further divided into nine to 13 subspecies, depending on who is doing the classification. One subspecies, the Arctic reindeer of eastern Greenland, is extinct.

2. Reindeer have several names.

Reindeer comes from the Old Norse word hreinin, which means "horned animal.” Caribou comes from Canadian French and is based on the Mi'kmaq word caliboo, meaning “pawer” or "scratcher," in reference to the animal’s habit of digging through the snow for food.

3. Santa’s reindeer are most likely R. tarandus platyrhynchus, a subspecies from Svalbard.

Svalbard reindeer
pum_eva/iStock via Getty Images

Clement C. Moore’s poem, "A Visit from Saint Nicholas,” introduced the world to Santa’s reindeer and describes them as "tiny." The only reindeer that could really be considered tiny are the Svalbard subspecies, which weighs about half as much as most reindeer subspecies and are at least a foot shorter in length. That may prove useful when landing on roofs.

Strangely, you’ll almost never see these guys in depictions of Santa. Live-action films usually use full-sized reindeer and animations usually draw the creatures as a cross between a white-tailed deer and a reindeer.

4. It’s not always easy to tell the sex of a reindeer.

In most deer species, only the male grows antlers, but that’s not true for most reindeer. Although the females in certain populations do not have antlers, many do. During certain times of year, you can still tell the sex of a reindeer by checking for antlers. That’s because males lose their antlers in winter or spring, but females shed theirs in the summer.

5. Santa’s reindeer may or may not be female.

Since reindeer shed their antlers at different points of the year based on their sex and age, we know that Santa’s reindeer probably aren't older males, because older male reindeer lose their antlers in December and Christmas reindeer are always depicted with their antlers. Female Svalbard deer begin growing their antlers in summer and keep them all year. That means Santa’s sled either has to be pulled by young reindeer, constantly replaced as they start to age, or Santa’s reindeer are female.

6. Reindeer were originally connected to Santa through poetry.

Before Moore wrote “A Visit from Saint Nicholas” (a.k.a. “The Night Before Christmas”) in 1823, no one thought about reindeer in conjunction with Santa Claus. Moore introduced the world to Dasher, Dancer, Prancer, Vixen, Comet, Cupid, Dunder and Blixem (the last two of which were later changed from Dutch to German, becoming Donner and Blitzen). While the first six names all make sense in English, the last two in German mean “thunder” and “flash,” respectively.

As for little Rudolph, he wasn’t introduced until catalog writer Robert L. May wrote a children’s book in verse for his employer, Montgomery Ward, in 1939 titled “Rudolph the Red-Nosed Reindeer.”

7. Reindeer are the only mammals that can see ultraviolet light.

Humans can see light in a range of wavelengths, from about 700 nanometers (in the red spectrum) to 400 nanometers (in the violet spectrum). Reindeer can see light to 320 nanometers, in the ultraviolet (UV) range. This ability lets reindeer see things in the icy white of the Arctic that they would otherwise miss—kind of like viewing the glow of a white object under a blacklight. Things like white fur and urine are difficult, even impossible, for humans to see in the snow, but for reindeer, they show up in high contrast.

8. Reindeer evolved for life in cold, harsh environments.

Migrating caribou
Geoffrey Reynaud/iStock via Getty Images

Life in the tundra is hard, but reindeer have it easy-ish thanks to their amazing evolutionary enhancements. Their noses are specially adapted to warm the air they breathe before it enters their lungs and to condense water in the air, which keeps their mucous membranes moist. Their fur traps air, which not only helps provide them with excellent insulation, but also keeps them buoyant in water, which is important for traveling across massive rivers and lakes during migration.

Even their hooves are special. In the summer, when the ground is wet, their foot pads are softened, providing them with extra grip. In the winter, though, the pads tighten, revealing the rim of their hooves, which is used to provide traction in the slippery snow and ice.

9. some reindeer migrate longer distances than any other land mammal.

A few populations of North American reindeer travel up to 3100 miles per year, covering around 23 miles per day. At their top speed, these reindeer can run 50 miles per hour and swim at 6.2 miles per hour. During spring, herd size can range from 50,000 to 500,000 individuals, but during the winter the groups are much smaller, when reindeer enter mating season and competition between the bucks begins to split up the crowds. Like many herd animals, the calves learn to walk fast—within only 90 minutes of being born, a baby reindeer can already run.

10. Reindeer play an important role in Indigenous cultures.

In Scandinavia and Canada, reindeer hunting helped keep Indigenous peoples alive, from the Mesolithic and Neolithic periods all the way through modern times. In Norway, it is still common to find reindeer trapping pits, guiding fences, and bow rests dating from the Stone Age. And in Scandinavia, reindeer is still a popular meat, sold in grocery stores in fresh, canned, and dried forms. Almost all of the animal’s organs are edible and many are crucial ingredients of traditional dishes in the area. In North America, Inuit rely on caribou for traditional food, clothing, shelter, and tools.

11. Reindeer used to live farther south.

Reindeer now live exclusively in the northern points of the globe, but when Earth was cooler and humans were less of a threat, their territory was larger. In fact, reindeer used to range as far south as Nevada, Tennessee, and Spain during the Pleistocene area. Its habitat has shrunk considerably in the last few centuries. The last caribou in the contiguous United States was removed to a Canadian conservation breeding program in 2019.

As for how Santa's nine reindeer manage to fly while pulling a sled carrying presents for every child in the whole world, science still hasn’t worked that out.

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