When it comes to teeth, there's always something new to learn. Innovations like fillings and toothbrushes had a long and rich history before they reached our mouths, and cultural norms can vary wildly — or be oddly similar — throughout place and time.
Which famous author became a tooth-removal evangelist? What animals have far more teeth than you’d expect? What kinds of small creatures gather baby teeth in the night?
Smile big and read on for eight facts that just might change the way you think about your pearly whites.
Tooth Enamel Is the Hardest Substance in the Human Body
Move over, bones! The outer layer protecting our teeth is the hardest thing in our bodies. The next layer down, dentin, is also stronger than bone. The trade-off is that teeth have a very limited ability to heal themselves, unlike bones. You can’t put a cast on a cavity, after all.
Snails Have Thousands of Teeth
Each unassuming snail hides a microscopic secret: between 1,000 and 12,000 tiny teeth protruding from its tongue. They use these teeth to break down parts of their food, and since the teeth are not especially durable, they need to be replaced pretty frequently. This tooth-covered tongue is called a radula, and it's not exclusive to snails. Slugs have them, too, along with some squids.
Not all radula are the same, though. Some predatory snails have venomous radula, and the terrifying-looking Welsh ghost slug has razor-sharp (and teeny-tiny!) teeth for eating worms.
The Earliest Toothbrushes Came From China
Tooth-cleaning goes back thousands of years, with methods including abrasive powder, cloth, and frayed sticks. Bristle toothbrushes emerged in China during the Tang dynasty (618–907 CE); the handles were made from ivory or bamboo. These brushes didn’t catch on in Europe until the 17th century, first in France and later in England.
While toothbrushes evolved in design throughout the 18th and 19th centuries, the materials stayed largely the same. Plastic handles came along in the early 1900s, and nylon bristles followed in 1938.
It Took a While to Get Americans to Brush Their Teeth
It sounds gross, but it’s true: Toothbrushing didn’t become a standard, everyday part of American life until the 1940s. That doesn’t mean all people didn’t brush their teeth — it just wasn’t the standard practice it is today.
The tide started to change in the decades prior, though. In the 1910s, schools started implementing dental hygiene programs like toothbrush drills, in which children practiced brushing their teeth with their teachers. Similar programs visited factories to care for workers’ teeth. This wasn’t just benevolence: Employers hoped their workers would miss fewer days of work due to tooth infections.
With dental hygiene already becoming normalized, one thing set it over the edge: American soldiers during WWII were required to brush their teeth every day, and brought the habit back home with them.
The Oldest Known Dental Filling Is Made of Beeswax
In 2012, scientists used the jaw of a Neolithic man to test out some new X-ray equipment — and in the process, made an exciting discovery. The man, who lived 6,500 years ago in modern-day Slovenia, had a filling made out of beeswax.
Drilling goes back even further than filling, though; archaeologists have found drill holes in teeth from more than 7,500 to 9,000 years ago in a graveyard in Pakistan.
Tooth Pulling Used to Be a Public Spectacle
Before modern dentistry existed, the task of tooth extraction in Britain fell to a strange assortment of professions, including blacksmiths, wigmakers, and a very specific kind of sideshow entertainer. Like snake-oil salesmen, charlatan tooth-drawers traveled to fairs and marketplaces wearing silly hats and sometimes even strings of teeth, eager to rip out teeth for curious spectators. They typically made a grand entrance, sometimes on horseback or with a team of assistants. Loud noises were a key part of the act, both to draw a crowd and to drown out the screams of their “patients.” This continued into the 1800s.
The alternatives, for what it’s worth, weren’t great either. In the 18th and 19th centuries, you could see a “barber-surgeon” (or later, just a surgeon) to get your painful tooth removed with a tooth key, a clawed device that looks a little like a broken corkscrew. All in all, it was not a great time to have bad teeth.
Tooth Fairy? More Like Tooth Mousie
Today, the most common American version of the tooth fairy is a small, whimsical figure, typically female, who checks under our pillows at night for lost baby teeth. But the tooth fairy is an early-20th-century invention, and that particular image rose to prominence right as Disney was releasing animated films featuring kind, gentle, feminine fairies.
The fairy is likely layered on top of a much longer tradition of offering baby teeth to rats and mice — the hope being that the child’s permanent teeth would grow in as strong as a rodent’s. While this practice appears throughout the world, it’s perhaps most common today in Spanish-speaking households. In fact, a specific tooth mouse named Ratoncito Perez emerged in Spanish lore in the 1800s, and spread throughout Latin America in children’s stories. A similar tooth mouse, La Petite Souris, goes back to 1600s France. In some countries, children make it more convenient for the rodent by placing their teeth in or near mouseholes.
The core concept — giving children money in exchange for teeth — dates back to at least the 12th or 13th century, and appears in Norse and Northern European tradition, while other lost-tooth rituals are common throughout the world’s history.
Roald Dahl Had All His Teeth Removed — Voluntarily — at 21
Famed author Roald Dahl was strange in many ways, including his strong opinions about teeth. When he was 21 years old and working at Shell Oil, he decided having teeth was just too much trouble, so he visited a highly regarded dentist in London to have them all taken out and an artificial set created. Five years later, he treated himself to extra-fancy new teeth with the sales from Shot Down in Libya, his first piece of paid writing.
This wasn't especially unusual for British people at the time, but it gets weirder: Dahl became a teeth-removal evangelist. He convinced his mother to have all of hers removed. Then he turned to his four living siblings, none of whom actually went for it; this made him impatient and “foul-mouthed,” according to biographer Donald Sturrock. Finally, he convinced his brother-in-law to go — but to Dahl’s surprise, he never got false teeth to replace them.
From castles, cathedrals, and palaces to miles-long bridges, golden temples, and sky-scraping glass towers, the world is full of magnificent feats of architectural engineering. While the purpose of most of these structures is known, there are still plenty of human-made monuments that boggle the minds of even the most acclaimed scientists and archaeologists. Here are 11 such monuments that remain a mystery.
Original photo by Stephanie LeBlanc/ Unsplash
Carnac Stones (France)
The Carnac Stones are a group of more than 3,000 megalithic standing stones in the French village of Carnac, Brittany. These stones date back to the Neolithic period and were probably erected between 3300 and 4500 BCE. They are one of the world’s largest collections of menhirs — upright stones arranged by humans. There is no real evidence to confirm their purpose, but that hasn’t stopped researchers from hazarding guesses. Some theorize they were used as calendars and observatories by farmers and priests. According to Christian mythology, the stones are pagan soldiers who were petrified by Pope Cornelius. Local folklore, meanwhile, says that the stones stand in straight lines because they were once part of a Roman army. The story goes on to say that the Arthurian wizard Merlin turned the Romans to stone.
Easter Island Moai (Chile)
Over 2,000 miles off the coast of Chile, Easter Island (Isla de Pascua) is the one-time home of a Polynesian people called the Rapa Nui. Scattered across the island are around 1,000 moai, giant hand-carved stone statues of human-like figures that are half-buried in the earth. The Rapa Nui landed on the island sometime between 700 and 800 CE, and are believed to have started making the moai around 1100 CE. Each moai weighs 14 tons and stands 13 feet tall on average, so it’s hard to imagine how they were transported and hauled into place. One theory is that the islanders used a system of ropes and tree trunks. Their purpose has also been the subject of much debate. To the Rapa Nui, the statues may have stored sacred spirits.
Nazca Lines (Peru)
Southern Peru’s Nazca Desert is covered with hundreds of geometric designs. These ancient geoglyphs range from simple shapes to plants and animals such as a hummingbird, monkey, llama, and whale. The Nazca Lines date back to around 200 to 700 CE, when the Nazca people who lived in the region created them. Researchers have struggled to agree upon the purpose of these giant works of art, particularly since they are best seen from the surrounding hills and by plane. Among many theories are astronomical maps, indicators of sacred routes, and water troughs. An alternative take is that they were created to be observed by deities from the sky.
Stone Spheres (Costa Rica)
In Costa Rica’s Diquis Delta is a group of around 300 polished stone spheres, some just a few inches in diameter and others measuring up to seven feet and weighing 16 tons. Employees of the United Fruit Company stumbled across the spheres in the 1930s while clearing a jungle to build a banana plantation. Scientists have so far been unable to pinpoint an exact date of their origin, instead suggesting that they appeared sometime between 200 BCE and the 16th century CE. They are commonly attributed to the Diquis people, yet their purpose is a mystery. They might have been property markers of ancient chiefs, and some even think they may be remnants of the lost city of Atlantis. Some of the spheres were even detonated in the hope of finding gold inside.
Temple of Bacchus (Lebanon)
The Baalbek temple complex in northeast Lebanon is one of the most intriguing Roman ruins on the planet. Its centerpiece is the well-preserved and monumental Temple of Bacchus. The age of the temple is unknown, although it was most likely erected in the second century CE. Most historians agree that emperor Antoninus Pius commissioned it in honor of Bacchus, the god of wine and intoxication. What has been baffling archaeologists ever since the temple’s rediscovery in the late 19th century is how the Romans succeeded in building it. It is staggering to think that humans without heavy machinery could hoist the 42 Corinthian columns (19 of which remain standing) of the colonnade, since each stands 62 feet tall and 7.5 feet in diameter.
Hagar Qim (Malta)
Located on the Mediterranean island of Malta, the UNESCO World Heritage Site of Hagar Qim is one of seven prehistoric temples in Malta and is believed to date to between 3800 BCE and 2200 BCE. The site’s name translates to “standing stones,” and one of the largest weighs in at more than 20 tons, measuring nearly 23 feet in height. The site was first excavated in 1839 and consists of a series of rooms lined by these megaliths. Parts of the chamber align with the sunrise and sunset of the summer solstice. This and the other temples on the island all appear to have been built in the same period, which has left archaeologists puzzled — there is little evidence of any civilization capable of such building feats on the islands at that time.
Göbekli Tepe (Turkey)
Could a set of ruins in southeastern Turkey be remnants of the world’s first temple? That’s one of the key questions archaeologists ponder as they explore Göbleki Tepe, a series of huge stone pillars that are some 6,000 years older than Stonehenge. Now a UNESCO World Heritage Site, the landmark was ignored for centuries, dismissed as little more than a cemetery. In the mid-1990s, excavations began and experts soon realized it was a treasure trove of history. The pillars weigh as much as 10 tons each and create massive stone circles. Radar surveys of the area indicate a number of additional circles are still buried underground. Göbleki Tepe is older than writing and older than agriculture. But who were the Neolithic people who built this, and how and why did they do it?
Yonaguni Monument (Japan)
Experts are divided as to whether the underwater rocks near Japan’s Yonaguni Island are a human-made structure or naturally occurring. In the 1980s, divers discovered what appears to be a rectangular monument, measuring 165 feet long and 65 feet wide. Some scholars believe that it is the remains of a pyramid, perhaps from a long-lost submerged city belonging to an ancient civilization. Meanwhile, others insist the rocks have been shaped by millennia of the ocean’s currents. Similarly, while some argue that markings on the rock’s surface are proof of ancient human involvement, others say they are simply scratches. For the time being, the Japanese government seems to agree with the latter and does not recognize the Yonaguni Monument as culturally significant.
Great Zimbabwe Ruins (Zimbabwe)
The Great Zimbabwe Ruins are the largest ruins in sub-Saharan Africa. This medieval city was once a trading hub and possibly the capital of the Queen of Sheba’s realm. The remains consist of the Great Enclosure (perhaps a royal residence), the Hill Complex (possibly the religious heart of the city), and the Valley Ruins (houses which suggest the city once had a population of 20,000 people). In total, the Great Zimbabwe Ruins extend across an area of 200 acres. The city is thought to have been abandoned in the 15th century, for reasons scientists aren’t sure of.
The Maya people of what is now Mexico were incredibly advanced when it came to writing, building, and knowledge of astronomy. Yet scientists still know little about other parts of their culture. By the time Spanish conquistadors arrived from Europe, the Maya civilization had already fallen, and historians still debate the cause. Some of the finest Maya ruins are at Palenque, in the Mexican state of Chiapas, an elaborate complex that includes a palace and several temples. Thought to have been constructed between 500 and 700 CE, it features plaster carvings and decorations that are still remarkably well-preserved. The city at Palenque is a marvel of design but remains shrouded in mystery since we may never know why it was abandoned around 900 CE.
No list of mysterious sites would be complete without the Neolithic monument at Stonehenge, which is known worldwide and continues to mystify visitors. The enormous stones are estimated to have been placed between 2500 BCE and 2200 BCE. Hundreds of even older burial mounds have also been uncovered in the surrounding area. Some of the stones come from several hundred miles away in Wales, leading archaeologists to speculate how they were transported. Others are from nearer parts of Wiltshire. What was Stonehenge’s purpose? Many believe it was a spiritual site, and people still flock to it as the sun rises on the summer solstice, when sunlight rises above the Heel stone at Stonehenge and falls directly onto the middle of the circle.