What Purpose Does the Belly Button Serve?

misuma/iStock via Getty Images
misuma/iStock via Getty Images

While your eyelashes are protecting your eyes, your lungs are letting you breathe, and virtually every other part of your body—inside and out—is performing its own relatively well-known task, your belly button is just sitting there collecting lint. And while it’s true that your navel served its most important purpose before you were born, it’s not totally useless now.

According to ZME Science, back when you were a fetus, your belly button was more of a belly portal: Your umbilical cord extended from it and connected you to the placenta on your mother’s uterine wall. That way, the placenta could channel nutrients and oxygen to you through the cord, and you could send back waste.

Your umbilical cord was cut when you were born, creating a tiny bulge that left behind some scar tissue after it healed. That scar tissue is your belly button, navel, or umbilicus. Though you may have heard that the shape of your belly button is a direct result of the scissor skills of the doctor who delivered you, that’s not true. Dr. Dan Polk, a neonatologist in the Chicago area, told the Chicago Tribune that a belly button's shape “has to do with how much baby skin leads onto the umbilical cord from the baby’s body. Less skin makes an innie; more skin makes an outie.” About 90 percent of people have innies.

Regardless of how your belly button looks, you probably don’t use it on a daily basis. However, if you’ve studied anatomy, medicine, or a related field, you might recognize it as the central point by which the abdomen is divided into the following quadrants: right upper, left upper, right lower, and left lower. Another way of classifying that area is into nine regions—including the hypochondriac, lumbar, iliac, epigastric, and hypogastric regions—with the umbilical region at the very center.

Abdominopelvic regions diagram
Blausen Medical, Wikimedia Commons // CC BY 3.0

Your belly button can also serve as the opening for laparoscopic surgery, which can save you from having a scar elsewhere on your abdomen.

The navel is a great central landmark outside of medicine, too. If you’ve taken yoga or Pilates classes, you may have heard it referred to as the center of balance or center of gravity. Because it sits right on top of your abdominal muscles, your belly button is an easy marker for your instructor to mention when they want you to access your core, which helps you balance.

And, of course, belly buttons are notorious for storing quite a bit of lint, which always seems to be blue (you can learn more about that here).

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Why Do People Toss Beads During Mardi Gras?

Kameleon007/iStock via Getty Images
Kameleon007/iStock via Getty Images

Each year, more than 1 million people descend on New Orleans for Mardi Gras, an organized parade of debauchery and alcohol-induced torpor that may be the closest thing modern civilization has to the excesses of ancient Rome. Saturating the scene on Bourbon Street are plastic beads, handed or tossed to partygoers as a kind of currency. Some bare their breasts or offer booze in exchange for the tokens; others catch them in the air and wear the layers around their necks. Roughly 25 million pounds of beads are in circulation annually, making them as much a part of the Fat Tuesday celebration as sugary cocktails and King Cake.

Traditions and rituals can be hard to pin down, but Mardi Gras historians believe the idea of distributing trinkets began in the 1870s or 1880s, several hundred years after French settlers introduced the celebration to Louisiana in the 1600s. Party organizers—known locally as krewes—handed out baubles and other shiny objects to revelers to help commemorate the occasion. Some of them threw chocolate-covered almonds. They were joined by more mischievous attendees, who threw dirt or flour on people in an effort to stir up a little bit of trouble.

Why beads? Tiny tokens that represent wealth, health, and other prosperity have been a part of human history for centuries. In Egypt, tokens were handed out in the hopes they would guarantee a happy afterlife; the abacus, or bead-based system of accounting, used trinkets to perform calculations; pagan pre-winter rituals had people throwing grains into fields hoping to appease gods that would nourish their crops.

Humans, argues archaeologist Laurie Wilkie, display "bead lust," or a penchant for shiny objects. It's one possible reason why Mardi Gras attracts so many people with their arms in the air, elated to receive a gift of cheap plastic.

Photo of a well-dressed bulldog celebrating Mardi Gras in New Orleans.
Mario Tama, Getty Images

The early beads were made of glass before more efficient production methods overseas led to an influx of plastic beads in the 1960s. Unlike some of the more organic predecessors, these beads have come under criticism for being a source of health problems and pollution. Made from petroleum, they often harbor lead that seeps into the soil and rubs off on hands. (One estimate puts the lead deposit after a Mardi Gras celebration at 4000 pounds.) In 2017, New Orleans paid $7 million in clean-up costs to remove discarded beads from drain basins. In 2018, they installed gutter guards to prevent the necklaces from getting into the system in the first place. Meanwhile, scientists have been working to create an even more eco-friendly version of the beads—like a biodegradable version made from microalgae.

Environmental hazards aside, the beads of Mardi Gras have become as much a holiday staple as Christmas stockings or Thanksgiving turkeys. But the passion and desperate need for them is only temporary; in 2018, 46 tons of the beads were removed from just five blocks of the main parade route on Charles Street. And no bacchanal should leave that much bad juju behind.

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Why Are Shower Doors in Hotel Rooms Getting Smaller?

sl-f/iStock via Getty Images
sl-f/iStock via Getty Images

Shower doors are shrinking in posh hotels, and minimalism is to blame, Condé Nast Traveler reports.

In lieu of hanging shower curtains or providing full shower doors, many newer hotels are opting for glass panels that cover only half the length of the shower. That’s frustrating for many travelers, who complain the growing trend is inconvenient and leaves bathroom floors sopping wet and slippery after shower use.

According to Condé Nast Traveler, the half-door trend began in European hotels in the 1980s. “A lot of it comes down to people trying to design hotel rooms with limited space,” boutique hotel designer Tom Parker told the magazine. “It’s about the swing of the shower door, because it has to open outward for safety reasons, like [if] someone falls in the shower. You have to figure out where the door swing’s going to go, make sure it’s not [hitting] the main door. It’s just about clearances.” A smaller door also has the added benefit of making the space appear larger than it really is, according to the magazine.

The trend is also connected to the birth of minimalist “lifestyle hotels,” which cater to a younger, hipper clientele that gravitates toward sleek lines and modern design. Plus, half-size glass doors are easier to clean than shower curtains, which tend to trap bacteria and need to regularly be replaced, which can add up to significant additional costs for a hotel.

Theoretically, even half-door showers are designed to minimize water spillage. Designers try to level the floors in bathrooms so water doesn’t pool in random areas, and they place shower heads and knobs in areas that are more protected by glass paneling. And where design doesn’t work, hotels try to pick up the slack.

“Hotels tend to mitigate the risks by offering non-slip interior shower mats, cloth bath mats for stepping out of the shower, grab bars, [and] open showers or no-sill showers which avoid having to step up and over the ledge,” designer Douglas DeBoer, founder and CEO of Rebel Design Group, told Condé Nast Traveler.

But the half-door trend still has yet to gain much love from hotel guests. “The older generation much, much prefers having a shower door,” Parker told Condé Nast Traveler. “I’m like a 70-year-old man at heart anyway. I like [a shower door] if it’s in keeping with the style of the rest of the room.”

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