Arachnophobia is among the most common phobias, and not just among humans. Spiders can have it too, and with good reason — spiders of certain species regularly eat each other (for food, after mating, and for other reasons scientists don’t fully understand). A 2021 study found that fear of fellow arachnids is prevalent among common zebra jumping spiders (Salticus scenicus), who were observed leaping away from larger jumping spider species in recognition of the latter’s status as potential predators. Even when placed near deceased Marpissa muscosa and Phidippus audax, the spiders froze up or ran away. The same effects were found even when baby Salticus scenicus were presented with 3D models that somewhat resembled the predators. Like their adult counterparts, baby jumping spiders have extremely strong eyesight and use their keen vision to detect and avoid threats — even when those threats aren’t actually moving.
Along with crustaceans, snails, and octopi, spiders do indeed have blue blood. That’s because their blood uses a protein called hemocyanin to carry oxygen around the body. Hemocyanin has a blue tint when oxygenated. Our blood, meanwhile, binds oxygen with hemoglobin, which looks red.
When it comes to humans, acrophobia (fear of heights), aerophobia (flying), trypanophobia (needles), and social phobias like public speaking also consistently rank among the most common fears. Approximately 19 million Americans have at least one phobia, most of which emerge when a person is between the ages of 15 and 20. Exposure therapy has been shown to help reduce these fears, at least when it comes to humans — jumping spiders may not be as lucky.
There are more than 45,000 species of spiders, and all but one of them are carnivores. The sole known exception is Bagheera kiplingi, which prefers a plant-based diet — for the most part, at least. Found across Latin America, the jumping spider is named in honor of both The Jungle Book’s black panther (Bagheera) and the book’s author (Rudyard Kipling). The arachnids reside in acacia trees and dine on nutrient-rich delicacies known as Beltian bodies (tips of the leaves of certain acacia species), which they steal from the ants who protect said trees. While these nutritious nodules make up 91% of their diet in Mexico and 60% in Costa Rica, B.kiplingi will occasionally drink nectar and, much more rarely, eat ant larvae, flies, or fellow spiders.
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Michael Nordine is a writer and editor living in Denver. A native Angeleno, he has two cats and wishes he had more.
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In the U.S., plenty of Chinese restaurant fare features produce that doesn’t grow in China, such as broccoli. Thus it shouldn’t be terribly surprising that Americans also took liberties with how Chinese food is packaged. While plastic containers are utilized to hold delivery and takeout dishes in China, diners in the States prefer a folded, six-sided box with a slim wire handle. Chicago inventor Frederick Weeks Wilcox patented this “paper pail” on November 13, 1894. Borrowing from Japanese origami, Wilcox elected to make each pail from a single piece of paper. This decision eventually proved critical in the transportation of Chinese cuisine, lessening the likelihood of leaks and allowing steam from hot foods to escape through the top folds. Another probable source of inspiration was the oyster pail, a wooden bucket with a locked cover that people used to carry raw oysters in the 19th century. Shortly after 1900, the company Bloomer Brothers started mass-producing Wilcox’s design specifically for toting oysters.
The Great Wall of China was partly built from rice.
One of the modern Seven Wonders of the World was made with help from grains. When portions of the Great Wall were constructed, the world's first composite mortar — a blend of heated limestone, water, and sticky rice — served as the binding agent for bricks.
As Americans began taking more advantage of suburban living and consumer conveniences after World War II, Chinese food delivery became an increasingly popular dinner option, with Wilcox’s containers of leftovers soon lining refrigerator shelves. During the 1970s, a graphic designer at Bloomer Brothers’ successor, the Riegel Paper Corporation, embellished the boxes to include a pagoda and the words “Thank You” and “Enjoy” — all in red, a color that represents luck in China. The Riegel Paper Corporation evolved into Fold-Pak, the world’s top producer of takeout containers, which assembles millions of cartons per year. Composed of solid-bleached-sulfate paperboard and boasting an interior polycoating, each food carrier expands into a handy plate if you remove the wire handle.
China’s flag is predominantly red, with five golden stars in the top left corner.
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It’s very likely that fortune cookies were invented in Japan.
Numerous descendants of Chinese and Japanese immigrants to the U.S. contend that their relatives created or sold fortune cookies in California between 1907 and 1914. However, Dr. Yasuko Nakamachi, a Japanese researcher who wrote her thesis on the origin of fortune cookies, has found evidence that the crispy treats were present in her home country many years prior. Fortune cookies in Japan go by several names, including tsujiura senbei (“fortune cracker”). They are mentioned in a story written in the early 1800s called “Haru no wakagusa,” known in English as “The Young Grass of Spring,” and in an illustrated storybook from 1878 called Moshiogusa Kinsei Kidan. In the book, a bakery apprentice is pictured working at a station labeled “tsujiura senbei,” grilling wafers in irons while surrounded by baskets of the finished product. This image is similar to what Nakamachi witnessed when she visited centuries-old family bakeries outside Kyoto: Cooks working over flames would dispense batter into grills containing round molds. Eventually, tiny paper fortunes were placed inside the warm cookies.
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Dogs are man’s best friend, and the canine ability to understand human words has gone a long way to solidify that world-changing relationship. According to the American Psychological Association, the average dog can understand 165 words, and “super dogs” — those in the top 20% of canine intellect — can understand around 250 words. Dog intelligence can be divided into three main types: instinctive (what the dog is bred to do), adaptive (what a dog learns from its environment), and working/obedience (what a dog is trained to do). Research into the levels of working/obedience intelligence in various dog breeds shows that border collies displayed the highest levels, followed by poodles, German shepherds, and golden retrievers. With the ability to also understand simple math (1+1 = 2, for example), these “super dogs” have an estimated cognitive ability equivalent to that of 2- to 2.5-year-old humans.
Recent research shows that dogs can make out yellows, blues, and hues in between. A dog’s retina has more rods than cones (humans are the opposite), and has only two types of cones. This makes dogs dichromatic, whereas humans, who have three types of cones, are trichromatic.
Although an understanding of 250 words is impressive, it’s by no means the absolute limit. The Einstein of the dog world is a border collie named Chaser. According to the journal Behavioural Processes, Chaser had the ability to recall and correctly identify 1,022 words. This far exceeds the vocabulary of any known dog, and pushes Chaser into the cognitive ability range of a 3-year-old. Now, that’s an extremely good girl.
The Labrador retriever was the most popular dog breed in the U.S. for 31 years.
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Humans and wild apes may share a common, nonverbal language.
Not all language is verbal, and scientists theorize that human language actually evolved from a gesture-based language in our species’ distant past. A study published in the journal PLOS Biology in 2023 analyzed the gesture-based language of chimpanzees and bonobos, the closest living relatives to humans. In the study, thousands of humans (5,656 to be precise) watched videos of chimpanzees and bonobos striking different poses, and were often able to correctly guess the pose’s meaning. (The meanings had been predetermined by researchers based on work with the apes.) Participants were correct slightly more than 50% of the time in a series of four-answer multiple-choice questions. The results suggest that humans retain an innate ability to understand at least some of the language of great apes, which includes call signals that may be precursors to our own language.
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The United States and its currency seem inseparably linked, but for much of the country’s history, an official, standardized U.S. dollar didn’t exist. In its place was a Wild West of currencies from competing banks located across several states. In their zeal to earn goodwill and customers, a few of these institutions even minted some rather creative banknotes. Instead of the chiseled visage of General Washington or other real-life American leaders, these notes featured the pudgy, bearded face of St. Nick, among other figures.
Franklin D. Roosevelt appeared on the $10,000 bill, the largest U.S. note ever circulated.
While Roosevelt’s face graces the dime, it’s Treasury Secretary and Chief Justice Salmon P. Chase whose visage adorns the $10,000 bill. However, in 1969, the U.S. Treasury purged the $500, $1,000, $5,000, and $10,000 bills from circulation. (They still remain legal tender.)
For the St. Nicholas Bank of New York City, featuring the bank’s namesake on its currency made some sort of sense. But other banks, seemingly unaffiliated with Father Christmas, also issued Santa money. For example, the Howard Banking Company issued its Sinter Klaas note in the 1850s, which depicted a St. Nick scene from Dutch legend. A total of 21 banks in eight states created notes featuring Santa Claus, with seven of them even printing an entire Santa Claus vignette on their currency. These fun funds came to an end in 1863, when the National Bank Act created a national currency in an effort to standardize banking throughout the U.S. While these Santa bills are now considered “obsolete,” the notes remain highly prized in certain collecting circles and are doing much more than just ho-ho-holding their value.
American author Washington Irving created the myth of Santa’s magic flying sleigh.
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Paper money isn’t made out of paper.
Most paper — think newspapers, cardboard, and notebooks — is primarily composed of wood pulp. But this kind of paper could never handle the rough life of a U.S. dollar. Instead of relying on trees, all U.S. currency uses the same blend of cotton (75%) and linen (25%) with red and blue synthetic fibers running throughout. This blend is what gives greenbacks their distinctive feel as well as their increased durability compared to normal paper. According to the U.S. Currency Education Program, USDs can survive 4,000 double folds (front and back) before tearing.
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Original photo by Claudine Klodien / Alamy Stock Photo
America has the eagle, England has the lion, and Scotland has the unicorn. And while the horned mythological creature may not actually exist, the traits it represents certainly do: Purity, independence, and an untamable spirit are all qualities Scotland has long cherished. Unicorns appeared on the country’s coat of arms starting in the 12th century, and were officially adopted as Scotland’s national animal by King Robert I in the late 14th century. For many years, the coat of arms included two of the legendary beings, but in 1603 one was replaced by a lion to mark the Union of the Crowns. Fittingly for the then-newly united England and Scotland, folklore had long depicted the two creatures as butting heads to determine which one was truly the “king of beasts.”
The world’s shortest regular commercial flight is in Scotland.
Just 2 miles separate the Scottish islands of Westray and Papa Westray, which means that the Loganair flight connecting them can last as little as 53 seconds. A number of locals depend on the eight-seat aircraft to go about their daily lives.
Scottish kings also displayed that fighting spirit, which may be why unicorns were generally depicted in Scottish heraldry as wearing gold chains — only the land’s mighty monarchs could tame them. Unicorns remain popular in Scotland to this day, with renditions found on palaces, universities, castles, and even Scotland’s oldest surviving wooden warship.
The Loch Ness monster was first written about in the year 565 CE.
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Royals used to test their food for poison with faux unicorn horns.
Neither unicorns nor their horns are real, but that hasn’t stopped people from attributing mystical properties to them for centuries. One case in point: European nobility circa the Middle Ages, who used so-called unicorn horns (also known as alicorn) to determine whether or not the meal they were about to consume had been poisoned. The “horns” were actually narwhal tusks in most cases, and were believed to sweat or change color if poison had been detected. Rhinoceros and walrus horns were also used — and all of these stand-ins could cost 10 times their weight in gold. Belief in their powers was widespread for centuries, with no less a monarch than Queen Elizabeth I being a devotee.
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Michael Nordine is a writer and editor living in Denver. A native Angeleno, he has two cats and wishes he had more.
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Even if you’ve never heard of a foramen ovale, you probably had one at one point in your life. It's the name given to the small opening between the upper heart chambers that forms as a baby grows in the womb and usually closes within the first few weeks of infancy.
Once a baby is born, the pressure caused by blood pumping through the heart usually closes the foramen ovale on its own. When it doesn’t close, it’s known as a patent foramen ovale (PFO) and usually has no ill effects; about 25% of the population have a PFO, most of whom don’t even know it.
Every cell in the human body gets blood from the heart.
The sole exception is the cornea, which has no blood supply at all.
The heart has four chambers — two atria on top and two ventricles below — and though no one’s sure what causes patent foramen ovale, genetics are assumed to play a role. The biology of infants is wonderfully weird in other ways as well. Babies are born with nearly 100 more bones than adults — about 300, whereas grownups have 206. Many of those excess bones are actually made of cartilage and fuse together throughout childhood.
The blue whale has the largest heart of any living creature.
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“Infant” comes from a Latin word meaning “unable to speak.”
We tend to think of the word “infant” as simply meaning a very young baby, with most people considering infancy to end at 1 year old. The word’s etymology is more specific, however: “Infant” comes from the Latin word infans, which means “unable to speak” or “incapable of speech.”
The Latin term has been in use since at least the 14th century, with “in-” meaning “not, opposite of” and “fans” meaning “to speak.” The word used to refer to children as old as 7, but its scope has since narrowed to our current definition.
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Rudolph’s nose may have been red, but his eyes were blue — except in the summer, when they would have been golden. That’s because reindeer eyes change color depending on the time of year, which helps them see better in different light levels. Their blue eyes are approximately 1,000 times more sensitive to light than their golden counterparts, a crucial adaptation in the dark days of winter. Only one part changes color, however: the tapetum lucidum, a mirrored layer situated behind the retina. Cats have it, too — it’s why their eyes appear to glow in the dark. This part of the reindeer retina shines a different hue depending on the season.
Unlike other members of the Cervidae (read: deer) family, both male and female reindeer have antlers. They have this in common with bovids (goats, sheep, and antelopes), whose females use their horns like female reindeer use their antlers: to protect their food and territory.
Rudolph and his eight friends aren’t the only animals with unique eyes. Chameleons can move theirs independently of one another, giving them nearly 360-degree views of their surroundings; goats’ distinctive regular pupils give them a panoramic view of the horizon, allowing them to detect predators early; and cuttlefish pupils resemble a “W” in bright light and a circle in the darkness of deep waters — to name just a few unusual animal peepers. Maybe those critters should get songs written about them, too.
Caribou, another word for reindeer, means “snow shoveler.”
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Rudolph was created for a department store.
Long before he made his television debut, Rudolph graced the pages of a coloring book handed out to children visiting Santa Claus at Montgomery Ward department stores. Catalog copywriter Robert L. May was commissioned to create a memorable character for those books in 1939, and his creation was wildly successful — 2.4 million copies were given out the first year alone. This was despite the fact that May’s boss initially disliked Rudolph’s red nose because it could imply that the animal had been drinking. Rudolph was a household name within a decade, with the song we all know and love (which happens to have been written by May’s brother-in-law) recorded by none other than Gene Autry in 1949. He really did go down in history.
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Michael Nordine is a writer and editor living in Denver. A native Angeleno, he has two cats and wishes he had more.
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While postal employees pride themselves on delivering mail in rain, sleet, and snow, they can still be impeded by sloppy handwriting.That’s why the U.S. Postal Service has a team of keen-eyed employees whose job is to determine where to send letters and packages with illegible addresses. More than 730 people work at the USPS Remote Encoding Center in Salt Lake City, Utah, which was the first facility of its kind and is now the last one standing.
Encoding centers peaked in 1997, when the USPS processed 19 billion pieces of difficult-to-read mail using 55 different facilities. But due to advances in computer analysis, as well as the fact that fewer people handwrite letters these days, just one facility dedicated to poor penmanship still operates today. The employees there play a pivotal role in analyzing the 3 million images of garbled addresses they receive each day.
The Hope diamond was sent by U.S. mail from New York to Washington, D.C., on November 8, 1958. It was shipped by jeweler Harry Winston as a donation to the Smithsonian, where it remains on display today. Winston paid $2.44 ($27.35 today) for postage.
Here’s how it works: Before ever reaching the facility, mail is scanned by a computer to determine its destination. While this step is often successful on its own, sometimes the writing is so indecipherable that the address remains a mystery. When that’s the case, an image of the letter is scanned and sent to the encoding facility, where the average employee can rapidly decipher 900 pieces of mail every hour. In some cases, unintelligible letters are brought in for a last-ditch physical inspection, after which mail is either sent on its intended way, returned to sender, or (in rare cases) disposed of.
The first woman to appear on a U.S. postage stamp was Martha Washington.
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There’s a floating post office with its own ZIP code.
The J.W. Westcott II, a mail-carrying boat that operates on the Detroit River, is the only floating post office in the United States. Its purpose is to deliver all mail addressed to crew members aboard the many freight ships that sail down the river. The boat uses a “mail in the pail” method, in which letters or packages are put into a bucket tied to a rope and hoisted onto the vessel.
The J.W. Westcott II was founded as a supply ship in 1874 and began doing mid-river mail transfers in 1895. It earned an official USPS contract in 1948 and was given its very own ZIP code, 48222 — the first nonmilitary floating ZIP code ever issued.
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When considering a final resting place, most people ponder the conventional options, such as a coffin or, for those who prefer cremation, an urn. Not Pringles inventor Fredric Baur, whose devotion to his innovative packaging method (which stacks his perfectly curved creations in a tall tube) was so intense that he had his ashes buried in a Pringles can. “When my dad first raised the burial idea in the 1980s, I chuckled about it,” Baur’s eldest son, Larry, told Time of his father’s wishes. But this was no joke. So after the inventor died in 2008, his children made a stop on their way to the funeral home: a Walgreens, where they had to decide which can to choose. “My siblings and I briefly debated what flavor to use,” Larry Baur added. (Sour cream and onion? Barbecue?) “But I said, ‘Look, we need to use the original.’” Baur’s ashes now rest, in the can, at his grave in a suburban section of Cincinnati, Ohio.
The chips were originally sold as Newfangled Potato Chips, but the name didn’t last. Some believe “Pringles” was taken from a street name in an Ohio telephone book, though this has never been confirmed.
Baur is far from the only person to choose an unconventional burial method — and many new choices have emerged across the world in recent years and decades. Star Trek creator Gene Roddenberry’s ashes were launched into space, a fitting resting place if ever there was one. Some people in Korea, meanwhile, have opted to have their ashes turned into sea-green beads that are placed in bottles or jars; the process is not unlike turning sand into glass. Those who prefer an environmentally friendly option, meanwhile, have encouraged the green burial movement, which prohibits spending eternity in nonbiodegradable containers — meaning that a Pringles container probably wouldn’t fly.
The name of the Pringles mascot is Julius Pringles.
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Pringles aren’t technically potato chips.
As far as the Food and Drug Administration is concerned, Pringles aren’t actually potato chips. Their main ingredient is dehydrated processed potato — not thin slices of fried potato, like in a typical chip — which led to a 1975 ruling by the FDA that they could only be labeled “chips” if they came with a disclaimer identifying them as “potato chips made from dried potatoes.” The company opted to market them as potato “crisps” instead.
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Michael Nordine is a writer and editor living in Denver. A native Angeleno, he has two cats and wishes he had more.
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Today, sharp-tongued verbal jousting primarily exists in the art form known as battle rap, in which two rappers take lyrical aim at each other with intricate (and often devastating) rhymes. During these battles, no insult — artistic or otherwise — is off-limits, and that’s a sentiment that 15th- and early 16th-century Scottish poets might have shared. Medieval Scottish men of words linguistically barbed each other in a practice known as “flyting” (based on the Old English word flītan, meaning “to quarrel”), often as entertainment for the Scottish king and his royal court. The most famous of these “battles” that still survives, known as “The Flyting of Dunbar and Kennedie,” featured Scottish poets William Dunbar and Walter Kennedy entertaining the court of James IV in the early 16th century. Among its many famous attributes, it’s the first recorded moment of scatalogical humor. (One of the more family-friendly examples of its insults, translated from Middle Scots, reads: “Grovel for grace, dog-face, or I shall chase you all winter; Howl and yowl, owl.”)
English is the only official language of Scotland.
While English is the most widely spoken language in Scotland, a bill passed in 2025 gave both Scots and Gaelic official language status alongside English.
The biting lyricism of flyting wasn’t restricted to Scotland, of course. Ancient Irish professional poets, called filid, were also known for their insults, and a form of flyting can be found in Old English literature as well as the famous Norse text the Poetic Edda (in which the trickster god Loki goes on the verbal offensive against his fellow deities). Similar art forms can be found in Japan, Nigeria, parts of the Middle East, and elsewhere. Although flyting didn’t survive the Middle Ages, its influence can be seen in works ranging from Shakespeare to James Joyce. Thankfully, the birth of the rap battle in the 1980s once again provided a much-needed venue for settling serious artistic beef — and it’s been a fixture of hip-hop culture ever since.
The first major named poet to write in the Scots language was John Barbour.
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The first major rap battle, in 1981, was a transformative moment in hip-hop.
In December 1981, at the Harlem World club in New York City, hip-hop emcee Busy Bee Starski finished a set by bragging about his superior lyrical skills compared to other popular hip-hop artists at the time. Unknown to Busy Bee, one of those artists was in the crowd — another emcee named Kool Moe Dee. The dissed emcee took to the stage and dished a lyrical attack right back at Starski. His sharp, biting freestyle juxtaposed with Busy Bee’s simpler, more comedic technique sent rap in a new direction, in which emcees became more focused on serious lyricism rather than the typical party persona. Kool Moe Dee’s “battle” was recorded and became an influential mixtape that found its way onto the radio, and around the world.
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