The idea of a tongue map has been discredited (but taste sensitivity varies across the tongue)

A timeline of the science of taste discoveries

The tongue is made up of four types of papillae—elevated, nipple-like projections that give the organ its rough texture. In the early 1900s, initial research into the tongue's varying taste sensitivity led to a misleading map of the tongue and its taste regions. Over the decades, researchers fleshed out five distinct tastes (and more recently, a sixth).

Breaking down various tongue disorders, from infections to genetics

Taste is one of our fundamental senses, but can be impeded by a wide variety of conditions including glossitis, angioedema, and black hairy tongue. Most are characterized by their color, shape, and sometimes change in function. Causes range from vitamin or mineral deficiencies to fluid accumulation, fungal infection, or more.

The research that led to sour

Scientists are trying to figure out if there are unique receptors that respond to the molecules that make up flavors we associate with calcium, blood, batteries, and other items that often escape dinner menus. Taste researcher Dr. Danielle Reed says the minimum evidence for a taste category typically involves identifying dedicated receptors and then removing them to show the taste vanishes.

Many parts of the body, including the testicles, have bitter, sweet, and umami receptors

Taste receptors—the tiny cells that report the chemical makeup of external stimuli to the brain—in the testicles don't "taste" in the same way as the gustatory ones you use to determine if there's enough sugar in your tea. Research suggests that these "teste" receptors can sense bitter, sweet, and umami compounds and use that chemical input to control physiological processes or (literally) change direction. (Some users may experience a paywall.)

How texture affects taste

Texture is the brain's interpretation of several sensations, including pressure, as registered by our teeth, tongue, and finger tips, and sound, as recorded by our ears. Texture also speaks to food particle sizes—smaller than 35 microns contributes to the sensation of creamy—and the balance between flavor and mouth time, such as the crunch of a crispy chip or the bounce of a chewy caramel.

The tongue evolved in animals roughly 350 million years ago

Creatures like fish rely on suction to consume food, flexing their gills to create water currents that vacuum up their meals. The evolution of the tongue enabled vertebrates to completely cut ties with the sea, moving onto land where they could sample new foods and ways to eat them.

Why are all maps of the world wrong?

This 5-minute video explains why all maps to date are verifiably wrong. While globes can provide an accurate map and scale of the various continents, flattening that sphere has historically meant something will be distorted, whether land, sea, or...

How do maps get their place names in multilingual areas?

In countries with multiple local dialects, cartographers struggle to standardize place names enough to create maps of the region. This process inevitably leads to conflict. Case in point, Switzerland, where in the late 1800s many dialects called the same places by different names, leading one alienated community to demand the return of its local names. Read about this and several other examples of contentious place-naming on maps here.

Cultivate your coffee taste with this interactive flavor wheel

Coffee is one of the more complex things humans consume, and taste can vary drastically based on bean genetics, roasting technique, and more. Using this flavor wheel, you can more accurately describe your coffee's aroma by starting from the center and moving outward.

Mapping the origins of the world's crops

Food has evolved alongside humanity, and through globalized trade, much of the world can enjoy foods once isolated to one region. Examine where your favorite foods originated from and see how diet differs across cultures with these interactive...

Why the Scoville scale for measuring a pepper's heat is outdated and inadequate for sauces

Developed in 1912 by American pharmacist Wilbur Scoville, the scale is a subjective test in which testers determine the dilution at which capsaicinoids—the molecules that give peppers their heat—are no longer detectable. Modern chemical analyses can accurately quantify the amount of these molecules in peppers, which are diluted to varying degrees in sauces, thus affecting their net spiciness.

A new tinnitus therapy involves mild electric tongue shocks and sound exposures

Lenire, an FDA-approved bimodal neuromodulation treatment approach for tinnitus, aims to teach the brain to distract itself from tinnitus. It includes short-term daily sessions wearing a mouth device that delivers mild electrical pulses to the tongue while listening to different sounds. (Some users may experience a paywall.)

Anosmia is the total loss of the sense of smell

This type of loss—due to disease or trauma—has ripple effects, including an altered or limited sense of taste. This video details the anatomy and physiology of our sense of smell and taste and how these senses are interrelated.

A 'fishy' scent does lead to mistrust

In experiments where people were exposed to a literal fishy smell they were less willing to cooperate with others in economic games requiring trust, but that wasn't the case when they were exposed to another bad odor—the smell of flatulence.

Color originates from the brain processing light of varying wavelengths

Various geometric models, including Newton's color circle of hue and saturation and the horseshoe-shaped XYZ space for mixing colors via vector mathematics, have been proposed to describe colors accurately. However, these models do not encapsulate the variety of psychological effects that cause perceived colors to differ from mathematical representations.

Examining self-diagnosed synesthesia

A growing number of people on social media claim to have a perceptual condition that lets them smell colors, see music, or taste sounds. But do they really?

Explore an interactive map built from more than 100,000 survey responses on where people find joy in their lives

Explore an interactive map showing what makes people happy

Using 10,000 responses collected from people around the world about what makes them happy, this map offers insights into how relationships, finances, purpose, and small treats all contribute to a person's contentment. Recent data suggests that young people today are less happy than those in previous generations, indicating a need to reflect on what really matters in life.

The 'sense' of direction comes from two strategies involving unique brain regions

Egocentric navigation utilizes the caudate nucleus and posterior parietal cortex, relying on a person's position in space to determine their direction of movement. Spatial navigation uses landscape features for orientation and is driven by the hippocampus.

A list of five scientific theories that were accepted and later disproved

Humoral theory held that everyone's personality derived from different combinations of four bodily fluids: blood, phlegm, yellow bile, and black bile. The phlogiston theory stated that all combustible materials possessed a fire element—phlogiston—that was released and absorbed by the air during burning. When the air became saturated with phlogiston, the fire would go out.

There's no right way to say 'taco'

While Americans ("tah-co") and Brits ("tack-oh") might argue about the correct pronunciation, both are understood in Spanish-speaking countries. Linguists note that the word's pronunciation is ever-evolving and informed by various cultural, psychological, and historical factors.

Home allergy tests don’t work well and experts urge caution

Doctors do not recommend at-home allergy test kits because their results may be inaccurate and confusing, and lead people to make lifestyle changes that are not warranted. Tests that require sending in a hair sample, for example, will not be helpful because hair does not have the relevant antibodies that blood testing would detect.

Blindfolded people could identify objects by touch alone a week after encountering them

These touch memories are more complex and durable than previously thought. In research published in 2018, blindfolded volunteers touched over 150 household objects for about 10 seconds each, and afterward correctly identified the objects more than 90 percent of the time when presented with the object and a similar one. Participants still knew most of the objects a week later with about 85 percent accuracy. (Some users may experience a paywall.)

Why diners and chefs are ditching the Michelin Guide

The Michelin Guide's influence appears to be waning, indicating a shift in the perception of fine dining in contemporary culture. Trends show that diners today prefer getting recommendations from more informal networks, especially after lackluster experiences at Michelin-rated restaurants. Some chefs claim the star ratings don’t significantly influence their business, and others reject the pressure of obtaining a Michelin star altogether. Read more about the shift in this article.

Cow tongue was once a Thanksgiving delicacy

Cow feet and tongue were sometimes included in mincemeat pies—a popular 18th-century dish. Josefa Hale, who inspired Lincoln to declare Thanksgiving a holiday, said they were “indispensable; but [hoped] this rich, expensive, and exceedingly unhealthy diet will be used very sparingly...”

Mapping hearing loss in the US

Nearly 10% of Americans suffer from some degree of hearing loss, measured as the inability to hear sounds lower than 25 decibels. The incidence of hearing loss increases with age and is typically higher among men. Recent analysis produced a puzzling observation researchers can't quite explain: There's a larger incidence of hearing loss among rural populations than in urban centers. Explore the data with this map and explainer.

At the beginning of the 20th century, a group of young men ate standard American food—replete with food additives like borax and formaldehyde—as part of government research to better understand food safety.

Clever Hans was a 1900s horse that was believed to be able to solve math equations, tell time, and read and comprehend German, until a psychology student discovered how he got his answers.

Tattoos remain visible on your skin thanks to immune cells called macrophages

Fear or disgust related to clusters of holes and cracks, called trypophobia, may stem from evolutionary processes to help us avoid pathogens.

The Dracula character, now seen as the vampire archetype, was inspired by a seafood-induced nightmare its creator experienced.

How the most famous Ebola book, The Hot Zone, which sold 3.5 million copies and was translated into 30 languages, got aspects of the disease so wrong.

The concept of phantom limbs, the perception that amputated limbs are still present, dates back to a French military surgeon in the 16th century.

The Great Salt Lake's distinct dual coloration results from high-salinity organisms that only live in the northern portion and produce a purple protein.

Georgia O'Keeffe's flower paintings are often assumed to be sexual, though the artist claimed she was simply interested in highlighting the beauty of flowers that most people neglect

Hookworm infection, though risky, may help fight certain autoimmune conditions by tamping down the immune system's inflammatory response.

Budweiser stores yeast derived from the original 1800s strain in a secret bunker, which only the Head of Yeast Management can access—not even the CEO

Many legends about George Washington, including his supposed wooden teeth and the story of cutting down the cherry tree, lack evidence.

The Brothers Grimm were lawyers before they were storytellers, but became interested in fairy tales as they began investigating how rules and customs had been passed down through cultures.

Poison ivy is in the same family as mangoes, cashews, and pistachios—and they all produce oily urushiol in their raw, unprocessed state—but they are typically prepared in ways to avoid causing human discomfort.

The American cockroach is actually from Africa, an apparent hitchhiker aboard ships carrying enslaved people, with evidence suggesting the bug may have arrived in the New World as early as the 1600s.

According to the physics of black holes, our 4D reality may be a hologram—a projection of information coded on a 2D surface on the edge of the universe.

Listen to an in-depth conversation on the links between Parkinson's disease and herbicide exposure and the challenging pace of scientific investigation.

Hurricanes, which rely on air consistently spinning in the same direction, cannot cross the equator because air curves in opposite directions north and south of it.

Famed poet TS Eliot rejected the manuscript for George Orwell's political fable 'Animal Farm,' writing that its criticism of authoritarianism was not 'the right point of view.'

Prince's sexually explicit 1984 track 'Darling Nikki' attracted the ire of the Parents Music Resource Center, an advocacy group that inspired the Parental Advisory sticker, even though the song ends with a Christian message.

Some Pokémon have been named after real and fictional organisms, while some real-world species have been named after Pokémon, such as Chilicola charizard and Binburrum zapdos.

Artificial coral reefs have been 3D printed from nontoxic, biodegradable terracotta clay, which coral polyps have used as a foundation for rebuilding marine ecosystems.

The identity of the Tank Man in the iconic photo from the 1989 Tiananmen Square protests remains unknown and was possibly killed.

The US Constitution is widely regarded as the longest-standing written national constitution still in force—see how it has influenced rights worldwide.