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More than five centuries after the Aztec empire’s fall to Spanish conquistadors in 1521, history buffs can’t seem to learn enough about the fascinating history of the legendary civilization. In fact, secrets are still being unearthed below the streets of Mexico City. Here are some of the fascinating facts we’ve unearthed about the daily life of this once-thriving society.

Aztec civilization, 15th century.
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They Didn’t Call Themselves Aztecs

As with many ancient societies, much of what we know about the Aztecs comes from written accounts from outside their culture — in this case, descriptions from Spanish conquistadors who arrived in modern-day Mexico around 1519. However, the community that modern historians call “the Aztecs” actually referred to themselves as the Mexica or Tenochca people. Both names come from the region where the empire once flourished — southern and central Mexico, along with the capital city of Tenochtitlan (modern-day Mexico City). The Aztec name likely comes from the Mexica origin story describing their homeland of Aztlan (the location of which remains unknown).

Nahuatl language historic sculpture.
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The Aztec Language Is Still Alive Today

At the height of the Aztec empire’s reign, Nahuatl was the primary language used throughout Mexico, and had been for centuries. Colonists arriving from Spain around the early 16th century introduced Spanish, which would eventually replace Nahuatl. But the Indigenous language isn’t at all dead; more than 1.5 million people speak Nahuatl in communities throughout Mexico, plus there are efforts in the southern U.S. to teach and revive the language. Spanish and English speakers who’ve never heard Nahuatl still know a few words with Aztec origins, such as tomato (“tomatl”), coyote (“coyōtl”), and chili (“chīlli”).

Manuscript of Aztec texts.
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The Aztec Empire Had Vast Libraries

Surviving accounts from Spanish colonists describe the voluminous libraries of the Aztecs, filled with thousands of books on medicine, law, and religion. But early historians didn’t give the Aztecs enough credit when it came to written language skills, once considering the hieroglyphic style used by scribes as primitive. Few written documents have survived the centuries since the Aztec empire’s disappearance, most destroyed by Spanish conquistadors. But more recent evaluation of the last remaining texts shows that the Mexica people had a sophisticated writing system on par with Japanese that may have been the most advanced in the early Americas.

Engraving print of Aztec women.
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The Mexica People Were Highly Educated

Aztec society had a rigid caste system dividing communities into four main classes: nobility, commoners, laborers, and enslaved people. Regardless of social standing, every child in the community attended school to receive specialized education, often for a role that was chosen at birth. Schools were divided by gender and social standing, though all Mexica children learned about religion, language, and acceptable social behavior. Children of nobility often received law, religion, and ethics training to prepare them for future leadership positions, and schools for commoners taught trade skills like sculpting, architecture, and medicine. Because Aztec culture centered on expansion and advancement through military strategy, teenage boys of all ages received military and combat training, while girls were educated in cooking, domestic tasks, and midwifery.

Aztec Tonalpohualli calendar.
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Aztecs Used Two Calendars

Mesoamerican calendars from societies of old have remained an interest to many people, especially those who speculate about astrological events or end of the world scenarios. But calendars used by the Aztecs weren’t too dissimilar from our own. The Mexica people relied on two simultaneous calendars: one 365-day solar calendar called the Xiuhpōhualli and a 260-day religious almanac called the Tōnalpōhualli. The solar calendar consisted of 18 months with 20 days, each month named for a significant festival or event. The religious calendar dictated auspicious times for weddings, crop plantings, and other events, using a 13-month calendar with each day represented by an animal or natural element instead of numerals.

Shoes of an Aztec chief.
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Aztecs Wore the First Rubber-Soled Shoes

Centuries before rubber became an everyday mainstay in modern products, the ancient Mexica people were harvesting and collecting rubber tree sap for a variety of uses. Archaeological digs throughout Mesoamerica have excavated rubber balls likely used in ceremonial games or for religious offerings, but historians in the early 2000s found that Aztecs also created rubber soles for more comfortable and protective shoes. Researchers believe that Mexica artisans blended and heated rubber tree sap and extract from plants to create the rubber mixture, which could then be shaped and used for shoes, rubber bands, statues, and more.

 Construction of the city of Tenochtitlan with floating fields.
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Farmers Created Floating Fields

Constructing the city of Tenochtitlan was no small feat for the early Aztec settlers, mostly because the city was built on water. While centered on an island within Lake Texcoco, the city expanded across the lake with bridges that reached its shores with aqueducts and canals that supplied Tenochtitlan with fresh water. Farmland wasn’t vastly available on an island of more than 400,000 people, leading Mexica farmers to create floating fields called chinampas. Gardens were constructed by weaving tree branches, reeds, and sticks between poles to create an anchored base covered with mud and dead plants that broke down into nutritious soil. Chinampas doubled as a sanitation system using human waste as fertilizer, which helped crops grow vigorously while protecting drinking water from contamination.

Nicole Garner Meeker
Writer

Nicole Garner Meeker is a writer and editor based in St. Louis. Her history, nature, and food stories have also appeared at Mental Floss and Better Report.

Original photo by Vladimir Vladimirov/ iStock

Even those unfamiliar with the details of the civil rights movement of the 1950s and ’60s can point to Martin Luther King Jr. and Rosa Parks as key figures of the era. A deeper dive will reveal names including A. Philip Randolph, James Farmer, Whitney M. Young, and Medgar Evers — leaders who earned their place among the luminaries of the period for spurring legal and social progress.

However, not everyone earned due recognition for their contributions, whether because of personality clashes or deep-seated prejudices that went beyond matters of race. Here are five lesser-known civil rights influencers who helped to change the course of history.

American civil rights activist Bayard Rustin.
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Bayard Rustin

Well before the nation watched the struggle for Black equality unfold on television, Bayard Rustin was at the forefront of a previous generation of activists as a co-founder of the Congress of Racial Equality (CORE). CORE’s main objective was to use “nonviolent direct action” while fighting for civil rights. Rustin later helped Martin Luther King launch the Southern Christian Leadership Conference (SCLC), and is credited as a primary organizing force behind the 1957 Prayer Pilgrimage for Freedom and the 1963 March on Washington.

But Rustin was also an openly gay man, and as such, was always in danger of being marginalized despite his obvious brilliance as an adviser and strategist. He was forced out of the SCLC after a congressman threatened to spread rumors about an affair between King and Rustin, and while he returned to pull together the March on Washington, internal opposition forced him to accept a lesser public role in the proceedings.

Rustin later served as president and co-chair of the A. Philip Randolph Institute, and continued his push for economic progress even as the wider public movement lost steam. By the time of his death in 1987, Rustin was something of a historical footnote, despite having his fingerprints all over the major civil rights victories of his day.

American Civil rights activist Claudette Colvin.
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Claudette Colvin

Nine months before Parks was arrested for refusing to surrender her bus seat to a white passenger in Montgomery, Alabama, the same thing happened to 15-year-old Claudette Colvin. So why was the Parks incident the one that ignited the Montgomery bus boycott and transformed the issue into a national story? As Colvin herself later conceded, the then-42-year-old Parks, a secretary for the NAACP, was considered by some to be a more respectable symbol for the boycott, particularly after it was discovered that the unwed teenager had become pregnant.

Nevertheless, Colvin wound up playing a crucial role as events unfolded, as she was named a plaintiff in the 1956 Browder v. Gayle case that challenged the constitutionality of Alabama’s segregated buses and provided the legal backbone for the boycott’s triumph. Colvin left Alabama soon after and spent most of the following decades living anonymously in New York City, though her contributions have finally earned some long-overdue recognition in recent years.

portrait of civil rights leader Fannie Lou Harmer.
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Fannie Lou Hamer

If King served as the face and eloquent voice of the civil rights struggle, then Fannie Lou Hamer represented its rank-and-file members who were sparked to action because they were “sick and tired of being sick and tired.” Born into a Mississippi family of sharecroppers, Hamer was fired after attempting to register to vote in 1962. She used that experience to fuel a tireless dedication to voting rights and launch the Mississippi Freedom Democratic Party (MFDP) in 1964.

That summer, Hamer entered the national spotlight with a powerful speech before the Democratic National Committee’s credentials panel in which she recalled being subjected to a brutal beating in jail. But her presence also underscored the limitations of her position in the pecking order; President Lyndon B. Johnson dismissed her as an ” illiterate woman,” and even ostensible ally Roy Wilkins of the NAACP said she was “ignorant.”

Still, Hamer kept up the fight for equal rights even as she struggled to summon the respect she deserved. She later spearheaded the foundation of the Freedom Farm Cooperative in 1969 and the National Women’s Political Caucus in 1971.

James Meredith relaxing at Howard House located within Dillard University.
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James Meredith

Even when compared to other activists who overcame intimidation and violence to participate in demonstrations, James Meredith stands out for his astonishing displays of courage. In the fall of 1962, the 29-year-old Air Force veteran integrated the University of Mississippi. His mere presence at the university caused an uproar and ignited a massive riot that drew 30,000 U.S. troops, federal marshals, and national guardsmen into the fray. Four years later, Meredith embarked on a solo “March Against Fear” out of Memphis, Tennessee, but was shot before he could complete the planned 220-mile walk to Jackson, Mississippi.

While he drew praise from King, most notably in the famed “Letter from Birmingham Jail,” Meredith was never one to conform to the expectations of others. In 1967, he raised eyebrows by endorsing the reelection campaign of former Mississippi Governor Ross Barnett, who once vehemently opposed Meredith’s entry into the state’s flagship university. Two decades later, after several failed attempts to run for office, Meredith supported the Louisiana gubernatorial campaign of former KKK grand wizard David Duke.

Today, a statue commemorating Meredith’s achievement stands on the Ole Miss campus, though the rest of his complicated story is often omitted from history lessons.

Portrait of Pauli Murray.
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Pauli Murray

Pauli Murray was enormously influential as a lawyer, writer, and teacher. She became California’s first Black deputy attorney general in 1945, as well as the first African American to earn a Doctor of Juridical Science from Yale Law School two decades later. Additionally, the acclaimed scholar saw her legal arguments used in the groundbreaking cases of Brown v. Board of Education (1954), which struck down segregation in public schools, and Reed v. Reed (1971), which extended the rights under the 14th Amendment’s Equal Protection Clause to women.

Publicly critical of the sexism rife within the ranks of the civil rights movement, Murray helped launch the National Organization for Women (NOW) in 1966. Eventually, she found herself out-of-step with its leadership and stepped away. On her own once again, Murray resigned from her teaching post and entered New York’s General Theological Seminary, en route to one final historic achievement in 1977 as the first African American woman to be vested as an Episcopal priest.

Tim Ott
Writer

Tim Ott has written for sites including Biography.com, History.com, and MLB.com, and is known to delude himself into thinking he can craft a marketable screenplay.

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It’s a shame that we don’t remember being babies, because infants have a fundamentally separate way of existing in the world. Their brains are wired differently from adult brains to help them survive as brand-new humans, and they experience everyday things for the first time. While we might not know a lot about lived baby experiences, we do know a lot of fascinating and weird things about their bodies and minds — including these seven facts.

Orthopedist examining a babies bones.
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Babies Have Nearly 50% More Bones Than Adults

The typical adult human body has 206 to 213 bones. Babies, on the other hand, have closer to 300 when they’re born. Many human bones start out as multiple bones and fuse into one as flexible, connective tissue called cartilage hardens. In infants, the skull is actually six bones; they overlap to help make birth a little easier. As the baby gets older, the skull stays flexible to allow the brain to grow.

Adults do, however, have at least two bones that babies don’t: kneecaps. When babies are born, those future bones are completely made from cartilage.

The birth of a child in a maternity hospital.
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Newborn Babies Have No Tears

Crying is very closely associated with babies, but oddly enough, newborn babies can’t make tears, just a lot of noise. The lacrimal gland, which produces tears, isn’t fully developed until after two weeks. It takes even more time for the lacrimal gland to produce enough liquid for the tears to actually be noticeable. Babies get their “real tears” at 2 or 3 months old.

Close-up of a crying baby girl.
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Babies May Cry With an Accent

It seems babies soak up the language around them starting before birth. In a 2009 study, researchers recorded 60 French and German babies crying and found that subtleties in their cries mimicked each language. French cries had a slight lilt, while German babies abruptly started and dropped off at the end. This means that not only can babies recognize and mimic the musicality of their parents’ language, but they likely pick it up while still in the womb.

A baby hand grasping on an adult thumb.
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Infants Have Reflexes That Adults Don’t

We all have reflexes, like putting our hands out when we fall or kicking when a doctor hits our knee with a mallet. These movements happen involuntarily. Babies are born with a ton of them, which eventually go away. One is the Moro reflex, more commonly known as the startle reflex. If a baby is spooked by something or their head moves rapidly, they’ll respond by flailing their arms out really quickly. Babies will also automatically grasp when the palm of their hand or the sole of their foot is touched. Some of these eventually become learned behaviors — like rooting when their face is touched, which helps them find a nipple — but most newborn reflexes are gone within a year, and some last only a couple of months.

A baby girl learning to walk with fathers support.
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Babies Can Sense Rhythm

In 2009, a group of researchers in the Netherlands played a rock drum beat to 14 newborn babies hooked up to an EEG, which measures electrical activity in the brain. Sometimes, they skipped a beat without disrupting the rhythm. Other times, they stumbled the beat in a way that broke the rhythm entirely. When they broke the rhythm, the babies had a brain response consistent with that of an adult control group. Basically, babies expected the next beat to come along in time, much like an adult would.

4 Months old baby girl lying on colorful play mat.
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Babies See Red First

Newborns that can see aren’t colorblind, but their brains don’t perceive colors the same way that older children and adults do. They can also only see about 8 to 10 inches in front of their faces at first. This is why babies tend to enjoy high-contrast, black and white images — they’re easy for them to see. A few weeks after birth, red comes into focus, followed by green. Infants can see a full range of color by about 5 months old, although still not quite as vividly as adults.

Detail of a newborn baby ear.
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Infants May Experience Multiple Senses at Once

Up to 4% of adults experience synesthesia, which means that two or more senses are tied together; for example, colors will play sound. (Notable names with the ability include painter Wassily Kandinsky, writer Vladimir Nabokov, and composer Franz Liszt.) Scientists have long suspected that infant senses are completely tied together, but since babies can’t describe their senses in the same way adults can, the hypothesis is pretty difficult to prove. One study from 2009, however, supports it. Researchers found that young infants associate shapes (a stand-in for graphemes, or written language) with colors — the most common kind of synesthesia in adults. The association wasn’t as strong with 8-month-olds, and was absent in an adult control group.

Sarah Anne Lloyd
Writer

Sarah Anne Lloyd is a freelance writer whose work covers a bit of everything, including politics, design, the environment, and yoga. Her work has appeared in Curbed, the Seattle Times, the Stranger, the Verge, and others.

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When it comes to human spaceflight, NASA and other space agencies around the world have their sights set on Mars. Humans have gazed upon this small pinprick of red in the night sky for millennia, and in that time, ancient astronomers, Enlightenment philosophers, and high-tech robots have learned a lot about our planetary neighbor. Named after the Roman god of war, Mars lies some 33.9 million miles from Earth at its closest possible approach. It’s during this precious moment of planetary alignment, which occurs roughly every two years, that NASA sends its scientific cargo toward the red planet. These six fascinating facts are the result of centuries of tireless research and scientific discovery, even as they hint at other mysteries yet to be answered.

Red planet with arid landscape, rocky hills and mountains.
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Mars Isn’t Really Red

“The red planet” is a slight misnomer. Martian rocks are filled with iron, and much like on Earth, if you leave iron outside in the elements it’ll eventually rust. The dust from these oxidized rocks gets kicked up into the atmosphere, creating the red hue stargazing humans see. But over the millennia, we’ve crept closer to our planetary neighbor for a better look — even dropping a few robotic rovers to do some poking around — and scientists have discovered that the surface of Mars is more yellowy-brown, sort of like butterscotch. In fact, Mars is a vibrant palette of gold, tan, brown, and even some green. NASA’s Curiosity rover also discovered in 2015 that if you dig only a few inches beneath the oxidized outer layer of the Martian surface, the soil is actually bluish-gray — not red at all.

Mars with its two cratered moons, Phobos and Deimos.
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Mars’ Moons Are Nothing Like Earth’s Moon

Ever since their discovery in 1877, the moons Phobos and Deimos — named after the Greek gods of fear and dread, respectively — have been something of a curiosity. Phobos orbits only 3,700 miles above Mars (compared to our moon’s 238,855 miles). Deimos, meanwhile, is relatively tiny at some 6.8 miles in diameter, making it one of the smallest moons in the solar system.

However, the biggest mystery about Mars’ moons is where they came from. One theory suggests that the two moons could have been formed from asteroids impacting the Martian surface, much like our moon. Alternatively, they could possibly be asteroids themselves, captured in orbit by Mars’ gravitational pull. Unfortunately, neither moon will be around forever. Phobos is slowly being pulled toward Mars and will eventually (in 50 million years or so) break apart, either forming a ring around Mars or impacting the surface. Deimos, on the other hand, is slowly escaping Mars’ gravitational clutches and will one day be flung into space.

A full disk view of the north polar ice cap of Mars.
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Mars Also Has Four Seasons

Seasons might seem like a feature exclusive to planet Earth, but Mars also experiences four distinct seasons. Because the Martian year is twice as long as Earth’s, its seasons are also double in length — stretching from 142 days in autumn to nearly 200 days in spring in its Northern Hemisphere. (Days on Mars are 24 hours, 39 minutes, 35.244 seconds.)

Mars’ ice caps grow during its winter period and recede, almost disappearing entirely, when spring turns to summer. Summer on Mars can be tumultuous: Because the Red Planet is closest to the sun when the Southern Hemisphere is tilted toward it, Martian summers in the Southern Hemisphere are much hotter than summers in the Northern Hemisphere, and this temperature difference creates strong storms. Martian summers are also far from hospitable, as lows reach -284 degrees Fahrenheit. However, summer highs can reach a balmy 68 degrees if you’re willing to brave those chilly nights.

Crater Water Ice on Mars.
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Mars Has Liquid Water

Earth is a water planet — 71% of its surface is covered with the stuff. Mars, on the other hand, has more in common with the Mojave Desert, but that doesn’t mean it isn’t sporting some H2O of its own.

Scientists have known for a while that water flowed on Mars in its distant past, but until recently, many believed that any water on the planet was currently locked up in its frozen ice caps or in Martian rocks. But in 2018, the European Space Agency’s Mars Express mission used ground-penetrating radar to explore Mars’ southern ice cap, and scientists were astounded to find that liquid water flowed a mile beneath the surface of a subglacial lake. Although temperatures there are far below water’s typical freezing point, salt deposits keep the water in liquid form. These pools beneath the icy surface are similar to Lake Vostok in Antarctica, and their discovery opens up an exciting new area for exploration.

Sample scoop and arm, Viking 1 Mission to Mars.
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Mars’ Soil Is Poisonous

With a nearly nonexistent atmosphere, freezing temperatures, and scarce water, Mars isn’t a place you want to stay if you’re a living, breathing organism. Even microbes can’t survive on the surface, because Mars’ soil is poisonous.

For more than 20 years, Mars rovers have analyzed soil samples in different parts of the planet and have found a ubiquitous compound known as perchlorate, a substance toxic to humans. Usually, microbes love perchlorates, but Mars’ particular conditions — especially its high abundance of UV light — turn the perchlorates into a toxic cocktail. In 2017, scientists recreated Martian conditions in a lab and found that UV rays broke down perchlorates into hypochlorite and chlorite, a mixture that’s fatal to bacteria. Within 30 seconds, all microbes exposed to this Martian soil facsimile were sterilized.

This photograph shows the Vehicle System Test Bed (VSTB) rover.
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Mars Is the Only Planet Entirely Inhabited by Robots

Scientists haven’t found life on Mars (yet), but that doesn’t mean Mars is a boring place. On July 4, 1997, NASA’s Pathfinder rover landed on the red planet, and in the quarter-decade since, NASA has sent four more rovers — Spirit, Opportunity, Curiosity, and its latest robotic addition, Perseverance (2020-2021) — to follow in its footsteps (or in this case, treads). The European Space Agency also hopes to send its rover, the Rosalind Franklin, to Mars by 2028. In addition to these rovers, Mars is also populated by robotic landers such as NASA’s InSight, several orbiters from space agencies around the world, and even a pint-sized robot helicopter. Mars might be void of life, but until humans put boots on Martian soil, the planet will continue to be a playground for one thing: robots.

Darren Orf
Writer

Darren Orf lives in Portland, has a cat, and writes about all things science and climate. You can find his previous work at Popular Mechanics, Inverse, Gizmodo, and Paste, among others.

Original photo by TatianaMironenko/ iStock

Pink is arguably one of the most popular tints in existence, and its warm tone is full of meaning both historical and cultural. Its importance shows up in the clothes we wear, the rooms we paint, and in some cultures, the accessories we use for our babies (though which ones depends on the time and place). These seven facts about the color pink may have you rethinking your relationship with this hugely popular hue.

Dianthus barbatus flowers.
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Pink Is Named After a Type of Flower

Although the word “pink” is most often associated with the light-hued tint of the color red, the word actually originated with a specific genus of flower: Dianthus. While flowers in this genus (there are more than 300 species) are often pink, the term for the flower may have originally referred to the perforated or frayed edges of the blossoms — at the time, the verb “to pink” meant to decorate with a perforated pattern. (Think “pinking shears.”) Over time, the meaning shifted from the pattern to the color.

This isn’t the only “chicken before the egg” moment on the color wheel — “orange” was originally a reference to the fruit, and then became entwined with the color itself.

Pink lake natural phenomenon in Western Australia.
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There Are Many Pink Lakes Around the World

According to at least one estimate, 117 million lakes exist on Earth, covering roughly 4% of its surface. Among these millions of lakes, most sport the bluish and brown hues commonly associated with landlocked bodies of water. However, there are a few lakes that stand out from the crowd, including more than two dozen or so pink lakes spread across the world.

Although pink lakes can be found on every continent except Antarctica, Australia has the lion’s share. One of its most pristine examples is Lake Hillier on Middle Island. While many lakes may be pink only a few months out of the year (during the warm, dry season), Lake Hillier has been permanently pink for centuries. This hue is caused by a salt-loving algae called Dunaliella salina, as well as a bacteria named Salinibacter ruber, which both produce pinkish pigments. Although it looks like a tasty bubblegum soda, it’s best not to take a sip — the lake is 10 times saltier than the ocean.

Spectral colors and abstract structure.
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Pink Is an Nonspectral Color

There have been some heated debates online about whether pink is a true color. The argument may seem strange at first, but technically the color pink doesn’t exist without a little help from our eyes. That’s because pink is a nonspectral color, meaning it isn’t represented by a specific wavelength of light in the electromagnetic spectrum. In other words, in order to get pink, you need to combine spectral colors — in this case, red and white — which makes pink a construction of our minds.

Yet many colors we know and love are similarly nonspectral. Purple is a big one: It’s close to indigo and violet but technically isn’t found in that 380 to 740 nanometer sweet spot. Brown is similarly a nonspectral color. So cut pink some slack: While it may not technically exist, it’s certainly easy on the eyes.

Group of men and women in pink.
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Pink Was Once Considered a Masculine Color

These days, a baby’s biological sex is often denoted using blue for a boy and pink for a girl. However, this is a relatively recent development. Back in the 18th century, boys wore blue and pink in equal measure, and as late as 1918, an article in the trade journal Earnshaw’s Infants’ Department described pink as a “stronger color [that] is more suitable for the boy.” By the 1940s, the U.S. marketing machine established the current color/gender rules, and remnants of this idea are still with us today. However, younger men are more comfortable with wearing pink, so it’s likely this arbitrary distinction will likely fade away, and color styles will return to their 18th-century roots.

Young woman lying down in bed, head on a pillow, enjoying her sleep.
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Some People Listen to Pink Noise To Fall Asleep

Similar to the electromagnetic spectrum and light, there is also a spectrum for sound that’s described using color. Most of us are familiar with “white noise,” which contains all the frequencies humans can hear in equal parts. (Its name comes from the visible light spectrum: Just as white light is made up of all the colors, white noise combines all the frequencies of sound.) Pink noise contains all sounds in this same spectrum, but emphasizes lower frequencies. Some things naturally create white noise, including waves crashing on the beach or rain falling, which are often soundscapes people turn to when in need of a good night’s sleep. But if that white noise machine maybe sounds a bit too grating, give pink noise a shot.

Pink palace Hawa Mahal, Jaipur, India.
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One of India’s State Capitals Is Named “The Pink City”

Originally founded in 1727, Jaipur is now the capital of the state of Rajasthan in northwestern India. While Jaipur is the region’s largest city, it’s also known for another startling characteristic — many of its buildings are painted in rosy hues. To understand this unexpected architectural choice requires a look back in history. In 1876, Maharaja Ram Singh, who ruled Jaipur from 1835 to 1880, painted the city’s buildings pink in preparation for a visit from Prince Albert Edward, Queen Victoria’s eldest son. The maharaja chose this specific hue because pink is traditionally associated with welcome and hospitality throughout India. Fast-forward nearly 150 years, and Jaipur is now one of the most Instagrammable cities in the world.

Newly discovered exoplanet GJ 504b pink planet.
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Scientists Discovered a Pink Exoplanet in 2013

Our solar system is filled with eye-popping color. Of course, there’s the “pale blue dot” known as Earth, but there’s also our next-door neighbor the red planet, as well as the calming, icy blues of Neptune, the tempestuous browns of Jupiter, and the butterscotch otherworldliness of Saturn. Our cosmic neighborhood doesn’t sport any pink planets — but the same cannot be said for the rest of our galaxy.

In 2013, NASA spotted a peculiar gas giant circling the star GJ 504 (faintly visible by the unaided eye in the constellation Virgo) some 57 light-years from Earth. This gas giant, simply called GJ 504b, is about the size of Jupiter — and it’s bright pink. NASA describes the color as a “dark cherry blossom,” and the shade is due to the planet “still glowing from the heat of its formation.” So while seeing this pink world would be quite the sight, best to scratch it off your bucket list unless your idea of a tropical getaway includes 460-degree Fahrenheit temperatures.

Darren Orf
Writer

Darren Orf lives in Portland, has a cat, and writes about all things science and climate. You can find his previous work at Popular Mechanics, Inverse, Gizmodo, and Paste, among others.

Original photo by EgolenaHK/ Shutterstock

There’s something about diamonds that catches our eyes and won’t let go. Humans have traded, gifted, and worn the brilliant gemstones for thousands of years, with the first known descriptions of them dating to the fourth century BCE. In the time since, diamonds have retained their value and splendor, though there’s more to these elegant gems than just their jewelry uses. Read on for six splendid facts about diamonds.

Portrait of Mary of Burgundy, standing to the right holding a ring.
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The First Diamond Engagement Ring Was Presented Nearly 550 Years Ago

Some historians believe ancient Egyptian couples were the first to exchange love-related bands, a practice eventually picked up by the ancient Romans. However, it wasn’t until 1477 that diamonds entered the picture. That year, Archduke Maximilian of Austria presented a diamond-bedazzled engagement ring to his future wife, Mary of Burgundy. Yet the diamond engagement ring trend wouldn’t trickle through all of society’s ranks until the early 20th century; as gems became more attainable, engagement rings often featured other precious jewels such as rubies, emeralds, and topaz, and were often picked based on the bride’s birthstone. Following the Great Depression, diamond monolith De Beers began marketing its stones as the ultimate symbol of love and commitment, a plan that would entirely change the jewelry-exchanging tradition.

diamond-encrusted drill bits used for dentistry.
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Diamonds Are Used for More Than Jewelry

Not every diamond will make the journey from below the Earth’s surface to a jewelry store — in fact, many never do. Around 30% of mined diamonds are considered jewelry-quality; the remaining 70% are less-appealing diamonds called “bort.” But these stones aren’t discarded, because they still have many practical uses outside of jewelry; a diamond’s sturdiness makes it particularly suited for use in medical devices, electronics, and industrial tools. Dentists rely on diamond-encrusted drill bits that can easily bore through teeth. Similarly, the gemstones are embedded into saw blades and other tools to strengthen their cutting abilities and boost their longevity. Some scientists believe diamonds may even be a helpful material in electrical power advancements, possibly used as efficient, durable, and heat-resistant transistors (aka the mechanism that regulates electrical signals).

The ' Cullinan ' Diamond.
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The World’s Largest Diamond Weighed More Than a Pound Before Carving

In 2021, the average engagement ring diamond clocked in at 1.5 carats, which is nearly microscopic when compared to the world’s largest known diamond. Called the Cullinan diamond (for Sir Thomas Cullinan, owner of the mine from where it came), the gem weighed in at 3,106.75 carats — about the size of a fist. It was pulled from the Premier Mine in South Africa in 1905, and eventually made its way to British King Edward VII, who arranged for the diamond to be cut by the Asscher Diamond Company in Amsterdam. Carving the precious stone was a massive feat; preparation took six months before the diamond was cut into nine large stones and 97 smaller ones. Several of the stones, which are among some of the largest and clearest diamonds ever unearthed, became part of the British crown jewels.

Details of jewelry for reparation, restoration and maintenance.
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Diamonds Can Actually Break

Diamonds are known for being particularly durable, though it is possible to damage one. Considered one of the toughest naturally occurring materials on the planet, diamonds are rated the maximum 10 on the Mohs scale, which ranks a mineral’s hardness when scratched. However, many jewelers warn that these virtually indestructible gemstones aren’t necessarily invincible; like any precious stone, diamonds have vulnerabilities. Inclusions — aka small imperfections deep within the stone, like cavities, specks, and cracks — can affect a diamond’s structural integrity, occasionally causing pressure to build up inside the stone. When hit in just the right way, the weakened gem can crack, chip, or break apart. Nearly all diamonds, even lab-grown versions, have some form of inclusion, though the odds of having a catastrophic break remain relatively rare.

large uncut diamond stone in a natural state within a mine.
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Earth Had Diamonds Before Dinosaurs

In 1948, diamond company De Beers launched its famous marketing campaign: “A diamond is forever.” While the goal was to boost diamond sales following the Great Depression and World War II, the phrase touched on something we know about diamonds: They’ve been around for what seems like forever. All diamonds found on Earth are estimated to be between roughly 1 billion and 3.5 billion years old, making even the youngest diamonds older than dinosaurs. Some geologists believe the Earth’s diamond cache formed in the first couple billion years of the planet’s existence, though knowing for sure is particularly difficult because the stones can’t be carbon dated (carbon dating only works on organic material less than 60,000 years old). However, inclusions in diamonds can offer some clues; whenever the imperfections contain other minerals, researchers can better estimate the entire diamond’s age based on when its contaminant was once present on the planet’s surface.

Spaceship takes off into the starry sky.
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There Are Diamonds in Space

Diamonds aren’t unique to Earth; they’ve also been found in the universe around us. Some are amazingly enormous — like the suspected star-turned-planet made entirely of diamond material, found nearly 4,000 light-years from Earth. It’s not the only celestial body with the gems, though; scientists have long suspected some planets in our own solar system experience diamond showers. Lightning storms on Saturn transform the planet’s methane gas into soot, which experiences enough pressure to likely transform into diamonds that then rain from the sky. Researchers have long suspected that a similar phenomenon occurs on Neptune and Uranus, where high temperatures and pressure combine to create diamonds that sink toward the planets’ cores. Space researchers have also discovered diamonds in meteorites, possibly created in ancient collisions between dwarf planets and asteroids before landing on Earth, where they continue to intrigue scientists as much as our own diamonds do.

Nicole Garner Meeker
Writer

Nicole Garner Meeker is a writer and editor based in St. Louis. Her history, nature, and food stories have also appeared at Mental Floss and Better Report.

Original photo by Anton Iakovenko/ Shutterstock

Women have contributed to almost every facet of life, from sports and science to art and politics. While some female role models are starting to get more recognition, we still tend to gloss over history’s supporting female characters — women who broke their own glass ceilings while serving others, smashing records, and pursuing personal passions. Here are a few stories you may have missed in history class.

Close-up of a stack of opened mailing letters.
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First Known Female Postmaster in Colonial America

Mary Katharine Goddard was among the first female publishers in the U.S., a socially precarious venture for a colonial woman during the country’s fight for independence. Working with her mother, Sarah, and brother, William, Mary Katharine founded multiple publications starting in the 1760s. William frequently traveled between cities to establish new papers, leaving the bulk of news collecting and printing to his sister. In 1774, he appointed Mary Katharine to run The Maryland Journal while he focused on other pursuits (such as lobbying for a national postal service) and served time in debtor’s prison. During the height of the Revolutionary War, Mary Katharine made a name for herself with fiery anti-British editorials. In 1775, she was appointed Baltimore’s first postmaster — likely the first woman to hold such a position in colonial America — and in 1777, Congress commissioned her to print copies of the Declaration of Independence. (Surviving copies feature her printer’s mark at the bottom.) Despite her success, however, Mary Katharine was pushed out of both roles at the war’s end. In 1784, William rescinded her title as publisher, creating a lifelong rift between the siblings. Not long after, she was also removed from her postmaster job on the basis of sex. She wrote to George Washington asking to be reinstated, but the President passed her complaint to the postmaster general, who left her plea unanswered.

A close up view of the Congressional Medal of Honor.
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First Woman Surgeon and Female Congressional Medal of Honor Recipient

Dr. Mary Edwards Walker was the second U.S. woman to receive a medical degree (following Dr. Elizabeth Blackwell), but she became known as the country’s first female surgeon. Following her medical school graduation in 1855, Walker went into practice with her husband and fellow doctor Albert Miller, though the Civil War would change the course of her career. Despite having a medical degree, Walker was denied work as a military surgeon in the Union Army because she was a woman. Instead, she volunteered at field hospitals in Washington, D.C., and Virginia until 1863, when Tennessee accepted her medical credentials and designated her as the Army’s first female surgeon. Walker’s proximity to battlefields put her at risk — in 1864, she was captured by Confederate troops and spent four months at the notoriously brutal Castle Thunder prison, where she suffered injuries that plagued her for the rest of her life. At the war’s end, Walker was awarded the Congressional Medal of Honor for Meritorious Service, an honor that Congress revoked in 1917 on the grounds that her medical work was not directly on the front lines. She refused to return the award for the remaining two years of her life and was posthumously re-awarded the medal in 1977. More than 100 years later, Walker remains the only woman to receive the Congressional Medal of Honor.

A look at a camera being used for television broadcasting.
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First Female TV Game Show Host

Actress Arlene Francis found her footing in entertainment as a radio host, but it was a TV first that catapulted her career to new heights. In 1949, Francis became the first woman to host a television game show in the United States. On Blind Date, a show Francis originally hosted over radio airwaves, male contestants competed for an all-expenses-paid outing with women hidden behind a wall, the obvious catch being that they couldn’t see their prospective dates and had to answer a litany of questions with the goal of being picked. Francis hosted the show for three years before moving on to films and Broadway stages, but her best-known role was a 25-year stint as a panelist on What’s My Line?, another TV game show.

A woman walking up the stairs of the Supreme Court.
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First Native American Woman to Argue a Supreme Court Case

Lyda Conley’s legacy was preserving that of her ancestors — specifically their final resting place. Conley acted as a staunch (and armed) defender of the Wyandot National Burying Ground, a Kansas cemetery at risk of sale and destruction some 60 years after its creation. The cemetery was established in 1843 following typhoid and measles outbreaks that took hundreds of Wyandot lives; the loss was a particular blow to an Indigenous community that was forcibly relocated thanks to broken treaties with the U.S. government and the cruel Indian Removal Act of 1830. In 1890, Kansas senators introduced legislation to sell the burial ground; although it failed, the effort encouraged Lyda Conley to attend law school to defend the very cemetery in which her own parents, siblings, and grandparents were interred. Conley was admitted to the Missouri Bar in 1902, and within four years put her legal skills to work as the federal government moved to sell the cemetery. Conley and her sister Lena began a legal and physical siege for its protection, building an armed watch station called Fort Conley on the grounds and warning, “woe be to the man that first attempts to steal a body.” In 1910, her legal fight made its way to the U.S. Supreme Court, where she became the first Native American woman (and third woman ever) to argue a case before the judges. While the court ruled against her, years of media coverage about the cemetery worked in her favor. In 1913, the Kansas Senate passed legislation protecting the cemetery, which was designated a National Historic Landmark in 2017.

View of a plane flying under the clouds in the sky.
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First Woman to Break the Sound Barrier

Aviator Jacqueline Cochran set more than 73 flight records during her lifetime, most for altitude and speed. In 1953, she also snagged the title for first woman to break the sound barrier. Her success was a product of her determination, which may have been honed during a difficult childhood; raised in Florida by a family with modest means, Cochran began working in a cotton mill at just six years old. At 10, she struck out on her own, working in salons for several years before launching her own cosmetics company in the mid-1930s. Around this time, in 1932, Cochran pursued her pilot’s license with the goal of more easily reaching cross-country clients and business partners. Instead, she found a new passion that led her to compete in air racing, where she began setting speed records. When World War II started a few years later, she shifted her focus again to find ways to put her talents to practical use. In 1941, Cochran recruited two dozen female pilots for the Air Transport Auxiliary, a World War II program that utilized civilian pilots to transport military planes. That same year, she became the first woman to fly a bomber across the Atlantic Ocean. And by late 1943, she was commander of the Women’s Air Force Service Pilots. Cochran continued flying after the war, with a renewed focus on speed; her reputation gained her access to military jets that helped her break records — including the sound barrier feat.

Red running track in The National Stadium of Thailand.
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First Woman to Win Three Track-and-Field Olympic Gold Medals in a Single Year

No one would have guessed that Wilma Rudolph would be known as the fastest runner in the world by age 20 — most doctors believed she’d never even walk as an adult. After contracting scarlet fever, pneumonia, and polio when she was young, Rudolph lost much of her mobility, then slowly recovered with the help of leg braces she wore for several years. By the time she was nine years old, the determined future athlete had regained her ability to walk and began playing basketball; in high school, she was scouted by coaches for her speed on the court. One of those coaches invited Rudolph to train at Tennessee State University, where she refined her high-speed sprinting skills. She and her track teammates made two trips to the Olympics — first in 1956, when she was still in high school, and again in 1960. It was at the 1960 Games in Rome that Rudolph claimed three gold medals in track-and-field: one each in the 100-meter and 200-meter races, and another in the 4×100-meter relay. She became the first U.S. woman to do so at a single Olympics, simultaneously breaking three world records for speed. Rudolph retired from sports two years later but took up coaching and became a goodwill ambassador to French West Africa. Her Olympic achievements helped pave the way for the Black female athletes who would eventually break her records.

Nicole Garner Meeker
Writer

Nicole Garner Meeker is a writer and editor based in St. Louis. Her history, nature, and food stories have also appeared at Mental Floss and Better Report.

Original photo by Bychykhin_Olexandr/ iStock via Getty Images Plus

The struggle for workers’ rights in the U.S. is a fight that’s existed since the nation’s founding. The first Monday in September is a celebration of and memorial to the many workers, unions, and activists past and present who’ve secured hard-earned wins to help make America a prosperous nation for all its citizens. At the same time, the holiday is also often a nationwide end-of-summer bash. These six facts explore the history, meaning, and myths behind one of the most-loved holidays on the calendar.

New York City, Union Square workingman's demonstration 1882.
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Labor Day Started as a New York City Parade

On the morning of September 5, 1882, some 20,000 union workers marched through lower Manhattan. According to one newspaper report, the crowd was filled with “men on horseback, men wearing regalia, men with society aprons, and men with flags, musical instruments, badges, and all the other paraphernalia of a procession.” The parade celebrated the labor of the city’s union workers, who actually had to sacrifice a day’s pay in order to attend the celebration — but what a celebration it was. After the parade, 25,000 union members and their families filled Wendel’s Elm Park at 92nd Street and Ninth Avenue for a post-parade party, where beer kegs were “mounted in every conceivable place.” On September 5 the next year, New York’s Central Labor Union celebrated its second Labor Day parade, and the late summer holiday became a tradition.

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The Holiday Was First Recognized by Oregon in 1887

Although New York held the first parades and even introduced the first legislation recognizing Labor Day, Oregon was actually the first to officially recognize the holiday, on February 21, 1887 (though the state reserved the first Saturday in June for Labor Day, rather than early September). Within the same year, Colorado, Massachusetts, New Jersey, and New York followed suit. It wasn’t until 1894 that Congress solidified Labor Day as a national holiday — the legislation was signed into law by then-President Grover Cleveland.

International Workers' Day In New York City.
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Most Countries Don’t Celebrate Workers in September

While reserving the first Monday in September for Labor Day hearkens back to the holiday’s New York origins, the decision was also designed to distract from a more unsavory moment in the history of U.S. labor relations. Most countries around the world actually celebrate unions and workers on May 1, otherwise known as International Workers’ Day. This international holiday actually has its origins in the U.S., when a clash between Chicago police and workers in 1886 left several dead and dozens injured. Known as the Haymarket Riot, the event went on to inspire International Workers’ Day in 1889. Uneasy honoring such a bloody moment in U.S. history — especially one that inspired widespread vitriol against labor unions — Congress and President Cleveland opted for a different date entirely.

The US Department of Labor Building.
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There Was a Labor Day Before There Was a U.S. Department of Labor

Although the 19th century gave birth to what eventually became Labor Day — along with many other important historical moments that defined the worker’s struggle in both America and the world — the U.S. Labor Department wasn’t established until more than three decades after that first parade down New York City’s streets. Although the U.S. did establish the Bureau of Labor Statistics in 1884 and the Department of Commerce and Labor in 1903, the modern U.S. Department of Labor wasn’t created until 1913, when lame duck President William Howard Taft reluctantly signed it into law. Taft had such strong concerns about the bill (he thought it would hinder efficient administration) that he only signed it into law mere hours before his successor, Woodrow Wilson, took office. Today, the Department of Labor oversees labor laws, guarantees workers’ rights, and ensures safe working conditions. In 1933 — two decades after its creation — the department also became the first to be led by a woman, Secretary Frances Perkins (who was later recognized as a saint in the Episcopal Church).

Cars travel outbound for Labor Day weekend.
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137 Million Americans Traveled for Labor Day in 2022

According to a survey conducted by The Vacationer, 53% of Americans traveled on Labor Day weekend in 2022, which equates to some 137 million people. This figure narrowly surpassed both Memorial Day and the Fourth of July as the busiest travel weekend in the U.S. Although most of that travel (about 36%) occurred via car, airports also tend to see a serious uptick of Americans traveling to popular domestic locations, such as New York, Los Angeles, or San Francisco, or even catching international flights to London, Rome, or Tokyo. In 2022, the Transportation Security Administration screened 8.76 million travelers — exceeding pre-pandemic numbers — with Friday marking the busiest day of the weekend.

White blouses on hangers.
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Yes, You Can Definitely Wear White After Labor Day

The color white has its advantages during the summer, as it’s the best hue (or combination of all hues) to reflect the sun’s rays, but why is there an informal rule forbidding the color after summer is over? The roots of the rule date back to the 19th century as a means for upper-class women to distinguish themselves. The idea was that white clothes were only appropriate for weddings and resort wear, and because Labor Day stood in as the unofficial end of summer (though the astronomical end occurs weeks later), white shouldn’t be worn after Labor Day. If you’re looking for logic, there isn’t any — it was just an arbitrary rule meant to exclude those who didn’t have well-established fortunes and were less in the know. Somehow, this arbitrary rule survived more than a century, though it isn’t really recognized today — even if that doesn’t stop some people from still mentioning this pernicious piece of class warfare.

Darren Orf
Writer

Darren Orf lives in Portland, has a cat, and writes about all things science and climate. You can find his previous work at Popular Mechanics, Inverse, Gizmodo, and Paste, among others.

Original photo by Jack_the_sparow/ Shutterstock

The facts that you take for granted are not always actual facts. Everyday superstitions, often known as old wives’ tales (despite plenty of traditional wise teachings from old wives) shape the way we view the world, and it doesn’t always occur to us to question them. Have you ever considered that gum doesn’t sit in your stomach for seven years, or that coffee doesn’t stunt your growth? Here are the real facts about seven old wives’ tales you may have heard.

Pregnant woman expecting baby girl, holding pink red shoes.
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You Can’t Tell a Baby’s Sex From the Bump

One of the most pervasive genres of old wives’ tales is sex determination during pregnancy — but you can’t tell a baby’s sex from the outward appearance of a pregnant person’s body.

According to one myth, if the belly is sitting high it’s a girl, and if it’s lower, it’s a boy. In another, extra weight out front means a girl, and extra weight around the hips and bottom means a boy. Both are false, and have more to do with the anatomy of the pregnant person, whether it’s a first pregnancy, and the position of the baby.

A floating breakfast tray in a swimming pool.
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You Can Swim Right After Eating

As a child, you may have been warned to wait a full 30 minutes after eating to jump in a pool or a lake, because not doing so could cause debilitating cramps that would cause you to drown. This is false. The reasoning behind the myth is that your body is using more blood to digest your snacks and doesn’t have enough left over to keep your arms and legs in swimming shape — and while the body does take a little extra blood to aid digestion, it’s not enough to give you more than a very minor cramp.

Aerial view of two kids popping gum bubbles.
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Swallowed Gum Doesn’t Stay in Your System for Years

Another common childhood myth is that when you swallow gum, it hangs out in your stomach for seven years. In reality, it makes its way through your body pretty quickly, except in extreme circumstances. But it is true that your body can’t digest it, so it comes out in the same form as when you first swallowed it. Too much swallowed gum can lead to intestinal blockages, but you’re not going to want to wait seven years to get that fixed.

Young woman holding a pink cup of coffee.
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Coffee Doesn’t Stunt Your Growth

A long time ago, studies suggested that coffee could cause osteoporosis, a condition that causes bones to lose density, so a myth developed that coffee could stunt your growth. Later studies showed no clear link between coffee drinking and osteoporosis — it’s just that people who drank more coffee tended to not drink as many calcium-rich beverages such as milk, and lack of calcium can contribute to osteoporosis. However, osteoporosis itself doesn’t tend to make people shorter (although it’s associated with bone fractures that can). Nevertheless, the old wives’ tale persisted. If you have growing left to do, just make sure to eat a balanced diet and get all your vitamins and minerals.

Holding tweezers and plucking gray hair from head.
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Pulling Gray Hairs Doesn’t Cause Two More To Pop Up

There’s a myth that if you pluck out a gray hair, two more will grow back, but it’s not based in fact. Every strand of hair on our bodies grows from its own single hair follicle, and one by one, those follicles eventually stop producing pigment. When that happens, the follicle grows gray or white hair, but it still only grows one single hair. It has no effect on the surrounding follicles — so plucking a gray hair affects only that hair.

You do, however, run the risk of zero hairs growing back from that follicle when you pluck one, so if you want to avoid bald patches, it’s best to leave them on your head.

Close-up of a person cracking their knuckles.
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Cracking Knuckles Doesn’t Cause Arthritis

When you “crack” your knuckles, the telltale popping that comes from your joints sounds a little distressing, and maybe irritating, but it’s not as dramatic as it sounds. The noise is caused by nitrogen bubbles popping in your synovial fluid, a substance that lubricates the joints. The bubbles come back in about 20 minutes.

Contrary to a popular belief, cracking your knuckles doesn’t cause arthritis or any other long-term damage, but it doesn’t cause a lot of short-term relief either. You might feel a little looser in the joints, but the effect is mostly psychological.

Fake spiders marching across bedding.
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You (Probably) Don’t Swallow Spiders in Your Sleep

You may have heard the urban legend that people swallow around eight spiders in our sleep every year, but you’ll be relieved to know that the number is closer to zero. We’re not especially appealing to crawl on, because even in our sleep we make a lot of noise and movement that spiders would be sensitive to. If a spider did crawl on you, it could wake you up before it became an accidental snack. It’s theoretically possible that a spider could crawl in your mouth while you’re sleeping, but it’s highly unlikely.

Sarah Anne Lloyd
Writer

Sarah Anne Lloyd is a freelance writer whose work covers a bit of everything, including politics, design, the environment, and yoga. Her work has appeared in Curbed, the Seattle Times, the Stranger, the Verge, and others.

Original photo by Eva-Katalin/ iStock

The Eiffel Tower is an iconic symbol of Paris, but over the years its presence has not always been so valued. It may be hard to believe now, but the Eiffel Tower was once met with contempt. Here are six things you might not know about the famed “Iron Lady.”

French engineer Alexandre Gustave Eiffel (1832 - 1923).
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The Eiffel Tower Was Not Designed by Gustave Eiffel

Gustave Eiffel did not actually design his namesake tower. While his company was responsible for its construction, it was his two senior engineers, Maurice Koechlin and Emile Nouguier, who dreamed up the famous structure. It was said that Eiffel was not overly supportive of the initial design (drawn by Koechlin). However, after some tweaks and additions made by the French architect Stephen Sauvestre, Eiffel changed his tune, supported the project and eventually bought the rights to the patented design

Construction of the Eiffel Tower.
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The Parisian Elite Originally Hated the Eiffel Tower

A group of 300 Parisian artists and intellectuals protested the Eiffel Tower during its construction, even going as far to call it “monstrous.” In 1887, they made their complaints public by publishing their feelings in Le Temps newspaper on Valentine’s Day in a piece titled “The Protest Against the Tower of Monsieur Eiffel.” The text declared that the obscene design of the Tower was not consistent with “French taste… art and history.” However, by the time the tower was completed in 1889, these complaints petered out when faced with the magnificent end result.

Workman shown atop the lofty Eiffel Tower.
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The Eiffel Tower Reached New Heights

At the time of its construction in 1889, the Eiffel Tower reigned supreme as the tallest building in the world at a staggering 1,063 feet (324 meters). It was finally outdone in 1930 by New York City’s Chrysler Building.

World Fair of 1889 in Paris. A view of the Eiffel Tower.
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The Eiffel Tower Was Supposed to Be Temporary

Erected in 1889, the famous Tower was built to commemorate the centennial of the French Revolution. It was originally given a lifespan of 20 years and was set to be demolished in 1909. However, the French decided to hang on to their precious tower once they realized the value of its radiotelegraph station (which proved very useful during World War I). It has since become a symbol of Parisian pride and a world-recognizable structure.

The Eiffel tower and the business district of La Defense are seen by night.
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It Was Used to Take Down Criminals and Protect Paris

During World War I, the Eiffel Tower played a critical role in protecting the city and proved useful in gathering evidence on spies. The French used the tower’s transmitter to disrupt the Germans’ communication. The Eiffel Tower’s wireless station also intercepted messages from the enemy, which resulted in valuable knowledge on the German army. Lastly, the same wireless station allowed telecommunication officers to get their hands on a coded message that led to the capture of Mata Hari, the famous 20th-century female spy accused of espionage on behalf of Germany.  

The sun sets on the Eiffel Tower and the Champ de Mars in Paris.
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The Eiffel Tower Moves

The metal material used for the Tower’s construction causes it to expand — and therefore grow — in the summer under the blazing sun. When the temperatures turn colder, the Eiffel Tower naturally shrinks again. The change in its height can be as much as 15 centimeters (nearly 6 inches). The top of the Eiffel Tower also sways in the wind, moving roughly 7 centimeters (nearly 3 inches) side to side.

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