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A small bridge marks the plate boundary

There’s an old steel bridge right in the center of Parkfield that crosses Little Cholame Creek, although what’s really interesting is what’s underneath. The San Andreas Fault runs straight through the middle. One end of the bridge sits on the Pacific Plate, the other on the North American Plate, with a sign pointing it out.

Parkfield sits at a fault-segment transition

Parkfield sits right where the San Andreas Fault has an odd kind of switch. Up north, the fault moves slowly, but down south, it locks up until it suddenly slips again. Parkfield is right at that handoff point. As such, it catches both kinds of movement from essentially sitting on the fault’s hinge.

Sensors record many tiny quakes

While most towns only feel the bigger shakes, Parkfield feels a lot of them. And that’s why there are so many sensors everywhere. Yes, scientists have put sensors in the hills and mounted them on poles, even burying them underground. Having all this equipment means that the tiniest of movements are also recorded, creating a huge quake log over time.

Magnitude-6 earthquakes on schedule

Interestingly, Parkfield gets a large earthquake almost on schedule every couple of decades. Big ones around magnitude six have popped up in 1857, 1881, 1901, 1922, 1934, 1966 & again in 2004. Of course, the gaps aren’t exact, as sometimes they’re 12 years, sometimes they’re 30. But the pattern’s been surprisingly steady for over a century.

Comparisons to California

California does get a lot of earthquakes. But what makes Parkfield stand out is how often its ground moves, as the town records tens of thousands of earthquakes each year, with most too small for anyone to feel. Most earthquakes in California come from activity in the Geysers geothermal field, while Parkfield’s activity happens naturally along the fault.

The 2004 mainshock

Parkfield’s last big earthquake was a magnitude 6.0 in late September 2004, just before lunch. The epicenter was a few miles southeast near Gold Hill. The tremor was strong enough to shake the whole area, but what’s interesting is that the scientists could precisely pin down the earthquake’s location to within meters. That sort of accuracy just doesn’t happen in most towns.

The next prediction

Scientists watch Parkfield quite closely, even though they no longer make specific predictions. The next magnitude-6 quake is definitely going to happen at some point, but the timing isn’t clear, with recent studies tracking stress changes & small shifts in the fault. The goal for scientists is to focus on continuous monitoring & readiness rather than naming a year.

How people live there safely day to day

People in Parkfield deal with earthquakes the way other California communities do. They prepare early. Apps like MyShake, for example, send warnings and give people a little pre-warning, while San Luis Obispo County pushes regular earthquake safety information. Plus, most buildings here follow California’s seismic codes.

What locals expect when it shakes

As small quakes happen so often here, many residents aren’t surprised when they feel a quick jolt. They might not even stop unless it’s strong enough to rattle shelves. The local media usually reports little to no damage for these routine quakes, but nobody takes their safety for granted. Larger events can happen with little warning.

Ranching in Parkfield

Yes, the town might be tiny, but ranching keeps it active in its own way. Families have been running cattle on the V6 Ranch for generations. They’ve managed to keep the ranch open for events & continue to have seasonal activities without turning it into a tourist trap. It’s one of those places where you still see working trucks pulling up to the local café after a long day.

Getting there

Anyone interested in visiting Parkfield should know that it isn’t exactly on the way to anywhere. You’ll need to drive through many county roads that wind through ranchland & low hills. But once you get there, it’s completely worth it. Where else can you find a town that has ground literally shaking underneath you?

The following sources were consulted in the preparation of this article:

1. The Parkfield prediction experiment
2. Scientific goals of the Parkfield earthquake prediction experiment
3. The Earthquake Prediction Experiment at Parkfield, California
4. Preliminary Report on the 28 September 2004, M 6.0 Parkfield, California Earthquake 
5. Field Trip Guide to selected features along the San Andreas fault near Parkfield, central California
6. Lists, Maps, and Statistics – Earthquake Hazards Program
7. Seismic attenuation and stress on the San Andreas Fault at Parkfield: are we critical yet?
8. 3.7-magnitude earthquake shakes northern SLO County in early morning hours

Featured Image Credit: Shutterstock.

Where and when it happened

Milton is a small town near Tacoma, Washington. The state’s primary elections took place on September 13, 1938, and locals went to cast their votes as usual, without knowing that a mule was one of the candidates on the ballot. There was only one person who knew what had really happened.

What office was actually won

The ballot slot wasn’t for city leadership, but for a Republican precinct committeeman. Essentially, this was a party position that helps manage neighborhood political stuff. But people voted for Boston Curtis because they were likely thinking it was a real person, not an animal. And certainly not a mule.

How Washington’s primary worked in 1938

Washington gave parties the same ballot sheets, and voters could pick whoever they wanted for each race, no matter the party. They put precinct posts on that same sheet. As such, many people likely skimmed right past the names without a second thought, and it was only in the 2000s that the state abandoned such a practice.

Who put the name on the ballot

So how did this happen? It was thanks to Milton’s own mayor at the time, Kenneth Simmons, who filled out the paperwork & submitted Boston Curtis’s “application.” He later claimed that it was meant to be a joke and didn’t think that the mule would actually win any votes. Some speculated he did it to prove how many people vote without thinking about the candidate.

How the filing was completed

Simmons pressed one of the mule’s hoofprints onto the paperwork instead of a signature. Yes, he used an actual hoofprint for the filing. It was this detail that made reporters fall in love with the story, which is probably why it spread so fast. Interestingly, the election officials approved the form without batting an eye.

What the ballots returned

When the votes were counted, Boston Curtis had received 51 votes and officially won the seat. However, nobody challenged it. Wire services picked up the story & newspapers from the U.S. to Canada were running quick blurbs about the “mule politician.” Time magazine also wrote a short piece on September 26 that helped to popularize the story even more.

What happened after the vote

There wasn’t a ceremony after the results came in. The precinct position had legal requirements that the mule obviously didn’t meet, so the seat was flagged as vacant almost immediately. In fact, the council treated it like any other election where the winner turns out to be ineligible. They had preparations in place, just not for mule candidates.

How long the “term” lasted

Technically, precinct committee officers serve until the next scheduled election. But Boston Curtis never officially held office. The vacancy rules kicked in as soon as the result was certified. The party didn’t leave the position empty for long. After all, they relied on these roles for their regular organizing, so while the mule “won,” there was no actual term. A real person stepped in later.

Whether the rules changed afterward

The election itself didn’t lead to sudden legal reforms. However, Washington did change how it handled vacancies & eligibility in the law. Modern statutes clarified that a precinct committee officer must be a registered voter and a party member, with such updates making the proceedings more explicit for cases like this.

What’s known about the mayor afterward

Kenneth Simmons didn’t disappear after his little stunt. Later, he played an important part in forming Bonney Lake, another town nearby, eventually becoming its first mayor in 1949. But it’s the mule prank that most people still remember Simmons for & it’s something people still talk about today.

The following sources were consulted in the preparation of this article:

1. National Affairs: Boston Curtis
2. Fauquier Democrat, Volume 33, Number 4234, 28 September 1938
3. History of Bonney Lake
4. Partisanship Redefined: Why Blanket Primaries are Constitutional
5. Washington RCW 29A.80.031

Featured Image Credit: Shutterstock.

Ancient Greek omens

Homer was an ancient Greek poet, and during his time, a sneeze could interrupt a conversation. It would instantly change how everyone interpreted what was said. In Homer’s The Odyssey, the characters see a single sneeze as a sign from the gods, and in real life, the ancient Greeks believed it made sense to say a quick blessing or nod afterward.

Rabbinic customs

Among Jewish communities, sneezing wasn’t something to ignore, with old rabbinic texts also mentioning sneezing as a good sign. This was especially important when someone was sick. People had set phrases, like wishing someone health in Aramaic, which was essentially the original form of “bless you” in a different language.

Renaissance etiquette

Erasmus wrote these rulebooks on manners, and in these books, he included notes on sneezing. He told kids how to cover their faces & avoid grossing out their peers, as well as how to politely respond when someone said something kind afterward. This made “bless you” less of a superstition and more a form of etiquette.

A Latin health wish

Across Europe, people used Latin to share their blessings after sneezes. One of them was prosit, and this essentially translates to you hoping that the sneeze would “do you good.” Such a short saying spread through schools & polite society all over Europe, until English speakers eventually created “God bless you.”

The plague connection

There’s a myth that the phrase came from Europe during the plague. People were terrified of sudden sickness, & sneezing made everyone uneasy because it could happen right before serious symptoms appeared. Apparently, this is where “God bless you” came from, as a way to pray that they’d be okay. But the phrase existed long before this time.

Islamic traditions

Muslim communities have a rather specific sneeze routine that goes back centuries. The sneezer thanks God & the listener answers with a mercy wish, and it’s something they teach in religious texts. To this day, many Muslim people still follow this tradition in their homes and mosques.

Soul-protection beliefs & the quick blessing

A long time ago, some people treated sneezes as dangerous moments for the soul. Yes, really. The idea was that something harmful could slip in while a person was sneezing, so saying “bless you” would stop that from happening. It may sound bizarre today, but it’s something people took rather seriously in the past.

Court etiquette

But not every culture supported the loud “bless you” we’re used to. In the 17th-century French court, people had to handle sneezes with a bit more polish, so whenever someone higher up the social ladder sneezed, you didn’t shout anything. You gave them a small bow or a hat tip & kept your mouth shut to let your manners do the work.

Modern English use

Over time, “God bless you” turned into just “bless you.” The religious side to it has disappeared for many English speakers. Even people who aren’t religious say it automatically. It’s one of those habits you pick up as a kid, and it’s unlikely to go away anytime soon.

The following sources were consulted in the preparation of this article:

1. Homer: The Odyssey Book XVII
2. Berakhot 57b:14
3. On Good Manners for Boys / De civilitate morum puerilium
4. Good Manners and Form (Al-Adab)
5. Religion and the decline of magic
6. The Omen of Sneezing
7. An allergic reaction
8. Bad language: a blessing in disguise
9. Les règles de la bienséance et de la civilité chrétiennes

Featured Image Credit: Shutterstock.

She opened the UK’s early internet link in 1976

During a time when computers were the size of fridges and they didn’t have fancy screens, Queen Elizabeth II actually launched Britain’s ARPANET node. This was a very early internet link for the UK. Her ceremonial “login” was tied to the same network, which eventually turned into the internet.

Her goodwill message is literally on the Moon

There’s a tiny silicon disk sitting near the Apollo 11 landing site that is engraved with messages from dozens of leaders. This includes Elizabeth II. Of course, the Queen herself never went to the Moon, but her words made the trip with the astronauts & were left behind on the lunar surface for good.

She was the first reigning monarch to visit Australia

It might sound strange, but in 1954, Queen Elizabeth II became the first reigning monarch to ever visit Australia. Other members of the royal family had visited before her, but never a reigning King or Queen. She traveled around the country meeting crowds & millions turned out, with the visit becoming a massive national event that people still remember now. 

She carried only cash on Sundays for church

Normally, Queen Elizabeth II didn’t bother with money at all. But Sundays were different. She used to keep a bill in her handbag so she could drop it into the collection plate at church, and it was either a £5 or £10 note, depending on the week. It was part of her weekly routine.

Her birthplace is now a Cantonese restaurant

The London townhouse where the Queen was born was at 17 Bruton Street in Mayfair. Except now, it doesn’t look regal anymore because it is home to a fancy Cantonese restaurant. That’s right. People eat dim sum where a future queen once lived because London doesn’t waste prime real estate.

She owned all dolphins, sturgeons & whales in the UK

The old rules about monarchs in the UK meant that any unmarked dolphins, whales, or sturgeons found in British waters technically belonged to her. In fact, they even had a name for them, which was “fishes royal.” But she didn’t exactly go around tagging sea creatures, although they legally were hers.

She used a single nail polish color for decades

For more than thirty years, the Queen’s nails stayed the same shade of pale pink, which was called “Ballet Slippers” by the nail brand Essie. She wasn’t someone who went for trendy colors. Instead, she went for that same bottle again & again, with her staff actually restocking before it ran out.

She could do a dead-on Concorde jet impression

The Queen apparently had a weird party trick. She could mimic the sound of a Concorde jet landing, and it wasn’t a delicate hum either, but rather a complete & accurate impression. It was something that she mostly did in private, of course. 

She never held a passport

As a head of state, the Queen never needed a passport, and she didn’t require paperwork to travel abroad. The Queen was essentially the issuing authority for passports in the UK. It was the same deal for driver’s licenses, as she legally didn’t have to carry one. Her car didn’t even need license plates.

She once partied incognito on V-Day

The Queen slipped out of the palace with Princess Margaret at the end of World War II, simply to join the massive street celebrations. They blended into the crowd & danced the conga with them, while also roaming through London all night. Hardly anyone realized the future queen was in the middle of it all. She claimed it was “one of the most memorable nights of my life.”

Her wedding tiara snapped on the big day

Right before her wedding ceremony, the diamond tiara she planned to wear suddenly broke. It completely snapped. As such, palace officials rushed Garrard’s jewellers in to fix it on the spot & they managed to repair it just in time. She walked down the aisle wearing it like nothing happened.

She had a personal bagpiper as a morning alarm

There was an official role called the Piper to the Sovereign. On mornings when she was in residence, the piper played for 15 minutes at 9 AM under her window, with the position dating back to Queen Victoria & continuing through Elizabeth II’s reign. Pipe Major Paul Burns was the last person to play for her, and he also played at her funeral.

The following sources were consulted in the preparation of this article:

1. How the Queen of England Beat Everyone to the Internet
2. Messages of Goodwill from around the world brought to the Moon by the Astronauts Apollo 11 c. 1969
3. The One Time a Week Queen Elizabeth Carries Cash
4. The Queen’s birthplace is now a Michelin-starred Chinese restaurant
5. The Queen’s special talent includes this ‘alarmingly accurate’ impression
6. The Queen owned swans, dolphins, whales, and sturgeons. Here’s who inherits them now.
7. Royal Passports
8. Did Queen Elizabeth and Princess Margaret Really Leave the Palace on V-E Day?
9. The Most-Loved Royal Wedding Tiara in History

Featured Image Credit: Shutterstock.

Pushcarts and penny ice paved the way

Before there were trucks, sweaty guys used to push carts with giant blocks of ice & chipped treats that they sold for a penny or two. These were in almost every city. However, the cities didn’t love it. Health inspectors & permits made selling harder, but those pushers created the first idea of mobile ice cream.

Good Humor’s 1920 Youngstown trucks

Harry Burt was an Ohio candy maker who wasn’t satisfied just making bars. Instead, he put freezers in trucks & handed out sticks covered in chocolate, while also making sure his drivers were dressed in crisp white. He used handbells bolted right to the truck to get people’s attention. Soon enough, the sound became so iconic that kids would drop everything at the first ring.

Burt, Epperson, and a 1920s license deal

Burt had patents for his chocolate-covered bars. However, Frank Epperson had his Popsicle patent too, with both thinking the other person was stepping on toes. Yet they decided to avoid endless court fights. In 1925, they signed a deal where Popsicle received fruit-ice and Burt got cream-based bars.

How music joined the route

At first, clanging bells did the job, but then came those catchy tunes. Vendors began adding little music boxes before transitioning into full speaker systems that played short public-domain songs on repeat. Some used ragtime riffs & others borrowed nursery melodies. Either way, neighborhoods could hear their truck long before they saw it rolling onto their block.

Permits and noise rules

But ice cream truck drivers couldn’t merely drive where they wanted to. No, cities like New York created permit caps & set rules on how loud, as well as how often, trucks could blast their music. Playing the jingle too late at night meant you risked a fine. Essentially, these local laws decided which blocks trucks could park at, and when.

Refrigerated units mounted to trucks

Previously, cold storage involved blocks of ice melting away fast, which was as messy & unreliable as it sounds. And then came Frederick McKinley Jones’s invention. He designed a gasoline-powered refrigeration unit that sat on trucks to keep everything properly frozen for hours, with his “Model C” becoming the standard for food haulers across the U.S.

Soft-serve machines

By the mid-century, ice cream was no longer just in bars or cups, as trucks began showing up with soft-serve dispensers built inside. The vendors simply pulled the handle and could swirl a cone right there at the curb. This was all thanks to new freezers that kept mixes stable enough to serve instantly, completely changing what a “truck cone” meant. The modern ice cream truck was truly born.

The following sources were consulted in the preparation of this article:

1. Informal Urbanism: Legal Ambiguity, Uncertainty, and the Management of Street Vending in New York City 
2. Patented process of making frozen confections
3. The Frozen Sucker War: Good Humor v. Popsicle
4. A Folklorist Looks at Ice Cream Vans
5. A 100-Year Review: Milestones in the development of frozen desserts
6. Frederick McKinley Jones: National Inventors Hall of Fame
7. Municipal Regulation of Food Vendors in a Time of Crisis: The Case of New York City

Featured Image Credit: Shutterstock.

What exactly was thrown

The word the Romans used was nuces, which essentially means “nuts.” However, it wasn’t just any kind of nut. Pliny the Elder, an ancient scholar who loved cataloging stuff, singled out walnuts, which they called nuces iuglande, and they apparently had a connection to the rowdy wedding songs that the ancient Romans sang.

When it happened during the ceremony

According to ancient sources, the nut-throwing happened right as the bride entered the groom’s house. It was the big entrance moment for the wedding, and the idea was to bring in a little extra luck as she crossed the threshold.

The practical explanations

Pliny’s explanation is rather interesting. He said walnuts were perfect for weddings because the seed is under two layers, the green husk & the hard shell. As such, they symbolized fertility. He also mentioned that the sound they make when hitting the ground counted as a lucky sign, although he did prefer the fertility angle.

What Virgil says the groom should do

Ancient Roman poet Virgil also wrote about the custom, literally telling the groom to throw nuts. He writes “sparge, marite, nuces” in Eclogue 8, which translates to “scatter the nuts, husband.” Virgil included the detail next to a part about lighting new wedding torches. As such, it was clearly part of the checklist for the event.

Who received the nuts

However, when they threw the nuts, they weren’t aiming at the bride, nor did they throw them into the air for the gods. They threw them to the boys. It worked a little like Halloween trick-or-treating, except instead of candy, the kids received walnuts & they had to scramble to get them.

Giving up nuts

In Roman culture, “giving up nuts” was a way of saying someone had outgrown their childhood games. Kids used to play with nuts like marbles. As such, at weddings, when guests handed nuts to boys, it was something that kids liked, so giving them up quite literally meant that you were no longer a child.

The following sources were consulted in the preparation of this article:

1. Pliny the Elder, The Natural History 15.86
2. C. Valerius Catullus, Carmina
3. Virgil: The Eclogues

Featured Image Credit: Shutterstock.

Georgia’s code regulates ice cream

The food laws in Georgia talk a lot about ice cream, just not in the way the viral story suggests. It talks about labeling requirements, and gives details about temperature & milkfat, even pasteurization, but one thing’s missing. There’s nothing about someone tucking a cone into their jeans.

Alabama’s ice-cream rules set standards

It’s a similar situation over in Alabama, as their regulations focus on how ice cream is made & sold. Things like factory inspections and truck licenses are important because they’re practical issues. Yet there isn’t a single line banning people from wandering around with a cone in their back pocket.

Kentucky’s statutes define ice cream

Kentucky’s laws are not much different. They define what counts as ice cream & talk about retail food safety, while also talking about sanitation rules. What they don’t do is tell anyone where they can put their dessert. There’s nothing about pockets or cones, and certainly nothing about a mix of the two. Suddenly, this rule doesn’t seem so believable anymore.

Horse-theft origins

So where did this myth come from? It’s the horse angle that usually keeps this myth alive, which states that thieves used ice cream as bait. Apparently, since the horses followed them willingly, they couldn’t be charged with theft, as they technically didn’t “steal” the animals. But the states’ theft laws already cover livestock in full detail. Taking a horse, bait or not, is illegal, and ice cream doesn’t create a loophole to allow people to do this, so it’s not true.

The earliest mentions of the law

Interestingly, this fake law first emerged in old trivia columns & jokey newspaper fillers decades ago. It became part of strange factbooks from the 1940s onward, alongside things like weird laws about animals. But the state codes from that era are completely silent on the issue. That’s rather damning evidence that it’s not real.

Kentucky’s public ice cream posture law

One version of the story claims that standing on one foot while eating ice cream in public was banned. It’s a claim you’ll see in trivia books & articles. However, the actual Kentucky statutes don’t contain anything like that, and there’s no archival trace of such a rule existing or ever being suggested. It’d be funny if this story were real, but sadly, it seems to be a complete fabrication.

The law rumor likely confused real livestock rules

The alleged law comes from a time when horses & mules wandered around more freely. To avoid theft, Georgia & Alabama had strict rules about luring animals off property, although people used sweets to tempt them. There were specific enticement laws to deal with that. It’s very possible that people misunderstood this law, leading to the ice cream law rumor.

The following sources were consulted in the preparation of this article:

1. 2024 Code of Georgia title 26 – food, drugs, and cosmetics
2. Alabama Administrative Code
3. 217.015 Definitions for KRS 217.005 to 217.215
4. 2024 Code of Georgia title 16 – Crimes and offenses
5. 2020 Georgia Code Title 26 – Food, Drugs, and Cosmetics
6. Breaking the ice (cream law)

Featured Image Credit: Shutterstock.

Cool hues make big steel feel lighter

Some steel bridges are painted pale blue or soft green, although not simply for looks. Those shades make massive structures seem a little less intimidating. In states like Minnesota & Maryland, they use cooler tones when they don’t want the bridge to dominate views of the local area, and doing so keeps things calm.

Blue-green palettes for lower arousal

Bridges near parks or rivers often have blue & green tones because those colors are linked to lower physiological arousal. Essentially, they help people stay steady and focused. You’ll usually see this color near quieter parkways, where the goal is to blend with the surroundings & make driving less stressful. Isn’t that nice?

Palettes account for color-vision deficiencies

A portion of the population sees colors differently, especially reds & greens. This means bridge colors can’t use those contrasts alone. As such, designers often pick orange or other high-visibility hues that are still clear for color-deficient drivers, so that the structure is easy to identify for everyone, no matter the lighting or distance.

Low-sheen finishes cut glare and workload

Unfortunately, glossy paint on bridges will cause glare straight into your eyes, which is especially common when the sun’s low. That’s why many agencies use matte or low-sheen finishes. It’s easier on drivers’ eyes & helps prevent you from squinting when you’re driving toward a brighter area.

Corridor palettes support quick recognition

Some stretches of highway feel cohesive, even when the bridges change. Usually, that’s on purpose. A lot of state agencies pick one color family and stick with it along the same route so that your brain recognizes it automatically after a few trips. You don’t spend extra energy figuring out where you are, making driving far easier. 

Yellow–green accents boost peripheral detection

Whenever designers want something to stand out in your side vision, they’ll use yellow–green tones. This specific shade is a sweet spot for how our eyes pick up color during the day, so details pop faster, especially at the edges of your view. You’ll sometimes see it on rails or secondary bits of a bridge.

Specific hues can guide emotional framing during approaches

Also, the colors leading up to a bridge can set the mood before you hit the span. Agencies choose natural tones on the approach, then cooler shades on the main structure itself. Such a switch helps keep the experience familiar instead of jarring. Essentially, they’re trying to keep you focused and comfortable as you roll through.

The following sources were consulted in the preparation of this article:

1. Traffic signal color recognition is a problem for both protan and deutan color-vision deficients
2. Effects on Heart Rate Variability of Stress Level Responses to the Properties of Indoor Environmental Colors: A Preliminary Study
3. Aesthetic Guidelines for Bridge Design
4. Aesthetic Bridges – Users Guide
5. The Impact of the Spectral Radiation Environment on the Maximum Absorption Wavelengths of Human Vision and Other Species
6. Evaluating the impacts of color, graphics, and architectural features on wayfinding in healthcare settings using EEG data and virtual response testing
7. Visual Detection and Recognition of Fluorescent Color Targets Versus Nonfluorescent Color Targets as a Function of Peripheral Viewing Angle and Target Size
8. How the characteristics of street color affect visitor emotional experience

If you get cut, you can bleed out and die. But if you get the wrong blood type in a transfusion, you can hemorrhage internally and suffer a fatal immune reaction.

Keep reading to learn about the different blood groups so that you can know what yours is all about.

Role of antigens

The antigens that determine your blood type are proteins and sugars found on the surface of your red blood cells. Your immune system will see these antigens as identifying markers to decide which cells are yours and which are “foreign.”

If you receive blood with antigens your body doesn’t recognize, your immune system will react against them.

The universal donor (O-Negative)

Type O-negative blood lacks A, B, or Rh antigens on the surface of its red blood cells. Since there are no markers for a recipient’s immune system to react to, Type O-negative donors can give blood to virtually anyone.

This is why it’s known as the “universal donor,” and why you’ll see so many commercials asking for O-negative blood specifically.

The universal recipient (AB-Positive)

AB-positive blood contains every major antigen, and as such, AB-positive individuals are known as “universal recipients.”

Because there is no foreign antigen for an AB+ person’s immune system to react to, they can receive Type A, Type B, Type AB, and Type O blood.

Most common (O-Positive)

The most common blood type in the world is Type O-positive. Around 37% to 40% of the population has this blood type. O-positive blood is not the universal blood type, but it can safely go to anyone who has a positive blood group.

Approximately 38% of Europeans and 37% of Americans have this blood type.

Most rare (AB-Negative)

Excluding the extremely rare anomalies like “Golden Blood”, AB-negative is the rarest blood type, with only about 1% of people carrying it around their bodies. It’s so rare that blood banks have a difficult time keeping enough supply on shelves.

The irony is that while AB-negative is one of the rarest types for whole blood donations, Type AB donors are actually “universal plasma donors.” This means their blood plasma is free of anti-A and anti-B antibodies, making AB plasma safe for any patient in need.

Mosquito attraction

Studies have shown that people with Type O blood get bitten by mosquitoes more often than those with Type A blood. However, your blood type isn’t the only factor.

Mosquitos also home in on your production of CO2, body temperature, and even specific bacteria on your skin. While Type O blood may be their preference, other factors play into why certain people get bitten more frequently.

Transplants can change blood type

Generally, your blood type cannot change. One exception to the rule is patients who receive bone marrow transplants. Since our bone marrow produces new blood cells, recipients of a bone marrow transplant will slowly start producing the same type of blood that the donor had.

Over time, the patient will produce more of the new blood type until eventually, their original blood type is gone.

Certain diseases target certain blood types

People with Type O blood are naturally more resistant to malaria because the cells that carry the disease cannot bind to O-negative cells as easily. However, they may be predisposed to attracting the bacterium responsible for cholera and stomach ulcers.

Some researchers suggest that blood types evolved as a defense mechanism depending on the disease climates they inhabited.

Animal blood types

Animals have blood types, too. However, their genetic markers are not the same as humans. Dogs, for instance, have over 13 different types based around something called DEA (Dog Erythrocyte Antigen).

Cats have three blood types: A, B, and (rarely) AB. Since animals have entirely different antigens than humans, there is no way for your cat or dog to receive a blood donation from you.

Origin of Type “O”

In 1900, Karl Landsteiner discovered A, B, and C blood types. He initially named the third type “C” because it did not have A or B antigens. Scientists in German-speaking countries started referring to this blood type as “null,” meaning zero. Over time, when the discovery made its way to English-speaking scientists, the O replaced the 0.

Your gut bacteria depend on your blood type

Believe it or not, about 80% of people secrete their blood-type antigens into other body fluids and even their digestive tract. Studies think these antigens may help certain bacteria thrive in your gut while deterring others.

While we know blood type can affect gut bacteria, it isn’t the only factor. So eating a “blood type diet” won’t likely work as advertised.

The following sources were consulted in the preparation of this article:

1. Yes, Mosquitoes Can Tell Your Blood Type
2. Know Your Blood Type Facts
3. How Your Blood Type Affects Your Wellness
4. Blood Types Explained – A, B, AB and O
5. Can My Blood Type Change?

There are sites across the globe, built from stone, earth, and wood. On this list are the oldest known buildings still standing today from every continent known to man.

Asia: Göbekli Tepe (Turkey)

Built around 9,500 BC, Göbekli Tepe in south-central Turkey may be the oldest known monumental architecture in the world. The complex is made up of large stone T-shaped pillars set in concentric circles, many of which are decorated with reliefs of hunting scenes and wild animals.

It was previously thought to have been solely a temple for ceremonies until archaeologists discovered the remains of what they believe to be dwellings that predate pottery and farming by thousands of years.

Europe: Knap of Howar (Scotland)

The Knap of Howar is considered to be the oldest standing, roofed building in Europe. Built nearly 5700 years ago as two connected thick-walled stone buildings, it is believed the Knap of Howar was used as a primary residence.

Archaeologists have discovered stone-built cupboards and partitions still standing inside the low door threshold buildings. They were part of a larger complex and have lasted 5,000 years because they were eventually buried beneath sand dunes.

South America: Caral-Supe (Peru)

Occupied as early as 2600 BCE, the Sacred City of Caral-Supe is the oldest center of civilization in the Americas. The city was not fortified with walls, which tells archaeologists that it was a peaceful place that must have traded with other civilizations for food that couldn’t grow in its fertile environment.

The largest building here is known as the “Pyramid Mayor.” This large stepped building features an inner circular plaza surrounded by towering stone monuments. Buildings in Caral were made using baskets known as “shicras,” which were woven grass bags filled with stones.

Africa: Pyramid of Djoser (Egypt)

Around 2667 BCE, the step pyramid of Djoser was built by the famous pharaoh’s architect, Imhotep. Initially built as a flat-roofed mastaba tomb, Imhotep decided to stack several more layers on top of the original mastaba.

What resulted was a six-step true stone building that would come to be known as a “step pyramid”. Built out of limestone instead of sun-dried mud bricks, this was the first major cut stone construction on the continent of Africa. The Pyramid of Djoser was built to stand the tests of time as a part of a large mortuary complex.

Australia: Rosemary Island Stone Houses

The oldest known buildings in Australia are the stone houses of Rosemary Island in the Dampier Archipelago off Western Australia. Built around 9,000 years ago, these circular arrangements of stones are the foundations of what were once dwellings.

They offer insight into the organized engineering and settled lifestyles of Indigenous Australians during the early Holocene era. Previously, historians believed ancient Australian life centred around nomadic hunter-gatherer activities.

North America: Pueblo Bonito (USA)

Located in the American Southwest is the Chaco Culture National Historical Park. Here you will find Pueblo Bonito, which translates to “Big House” in the Native American Spanish tongue. Built between 850 AD and 1150 AD, this “great house” was the center of the Chacoan world.

Containing over 600 rooms and 24 kivas, it was the largest apartment-style building in North America until modern times. Pueblo Bonito is special because their masonry hints that the Ancestral Puebloan who lived here understood both solar and lunar cycles.

Antarctica: Discovery Hut (Ross Island)

Antarctica is unique in that it has no indigenous population, so the continent’s oldest building is quite new in comparison to other areas of the world. Built by British National Antarctic Expedition leader Robert Falcon Scott and his team in 1902, Discovery Hut was a prefabricated wooden building sent over from England in an Australian outback style with a large veranda.

This building did not keep heat very well. It still stands on Ross Island today in an amazingly preserved state due to the freezing temperatures. Supplies, crates, and even seal blubber from the earliest period of Antarctic exploration are still inside.

The following sources were consulted in the preparation of this article:

1. Evidence of 9,000-year-Old Stone Houses Found on Australian Island
2. Discovery Hut
3. Pueblo Bonito
4. We Might Finally Know How Egypt’s Oldest Pyramid Was Built
5. Sacred City of Caral-Supe
6. Knap of Howar
7. Göbekli Tepe