The 3,300-year-old burial mask of Tutankhamen was reportedly broken by a cleaner who then stuck it back together with cheap superglue.

The mask was discovered in 1922 by British archaeologists Howard Carter and George Herbert and is on display in the Egyptian Museum in Cairo. It’s made from 11kg of solid gold.

It also now sports an ugly gap between the face and the beard. The Associated Press reports it was also scratched by one employee using a spatula to try to scrape off the excess dried glue.

The AP reports the accident has only just come to light, but happened some time around October last year.

London-based Arabic news site Al Araby Al Jadeed said lighting around the mask has been dimmed in an attempt to hide the damage.

Officials at the Egyptian Museum in Cairo are yet to get the full story on how the mask’s blue-and-gold beard came to be broken.

Museum workers have different stories about the accident, but it’s clear the beard was stuck back on with “a very irreversible property”.

“Unfortunately … epoxy has a very high property for attaching and is used on metal or stone but I think it wasn’t suitable for an outstanding object like Tutankhamen’s golden mask,” one conservator told the AP.

One source from the scene claims the beard was actually taken off because it was loose.

Another report from Cairo Scene claims the head of the museum’s renovations team called her husband when the mask was discovered broken, who went ahead with the epoxy fix.

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A text that may be the oldest copy of a gospel known to exist — a fragment of the Gospel of Mark that was written during the first century, before the year 90 — is set to be published.

At present, the oldest surviving copies of the gospel texts date to the second century (the years 101 to 200).

This first-century gospel fragment was written on a sheet of papyrus that was later reused to create a mask that was worn by a mummy. Although the mummies of Egyptian pharaohs wore masks made of gold, ordinary people had to settle for masks made out of papyrus (or linen), paint and glue. Given how expensive papyrus was, people often had to reuse sheets that already had writing on them.

In recent years scientists have developed a technique that allows the glue of mummy masks to be undone without harming the ink on the paper. The text on the sheets can then be read.

The first-century gospel is one of hundreds of new texts that a team of about three-dozen scientists and scholars is working to uncover, and analyze, by using this technique of ungluing the masks, said Craig Evans, a professor of New Testament studies at Acadia Divinity College in Wolfville, Nova Scotia.

"We're recovering ancient documents from the first, second and third centuries. Not just Christian documents, not just biblical documents, but classical Greek texts, business papers, various mundane papers, personal letters," Evans told Live Science. The documents include philosophical texts and copies of stories by the Greek poet Homer. [See Images of Early Christian Inscriptions and Artifacts]

The business and personal letters sometimes have dates on them, he said. When the glue was dissolved, the researchers dated the first-century gospel in part by analyzing the other documents found in the same mask.

One drawback to the process is that the mummy mask is destroyed, and so scholars in the field are debating whether that particular method should be used to reveal the texts they contain.

But Evans emphasized that the masks that are being destroyed to reveal the new texts are not high quality ones that would be displayed in a museum. Some are not masks at all but are simply pieces of cartonnage.

Evans told Live Science, "We're not talking about the destruction of any museum-quality piece."

The technique is bringing many new texts to light, Evans noted. "From a single mask, it's not strange to recover a couple dozen or even more" new texts, he told Live Science. "We're going to end up with many hundreds of papyri when the work is done, if not thousands."

Debate

Scholars who work on the project have to sign a nondisclosure agreement that limits what they can say publicly. There are several reasons for this agreement. One is that some of the owners of these masks simply do not want to be made known, Evans said. "The scholars who are working on this project have to honor the request of the museums, universities, private owners, so forth."

The owners of the mummy masks retain ownership of the papyrus sheets after the glue on them is dissolved.

Evans said that the only reason he can talk about the first-century gospel before it is published is because a member of the team leaked some of the information in 2012. Evans was careful to say that he is not telling Live Science anything about the first-century gospel that hasn't already been leaked online.

Soon after the 2012 leak, speculation surrounded the methods that the scholars used to figure out the gospel's age.

Evans says that the text was dated through a combination of carbon-14 dating, studying the handwriting on the fragment and studying the other documents found along with the gospel. These considerations led the researchers to conclude that the fragment was written before the year 90. With the nondisclosure agreement in place, Evans said that he can't say much more about the text's date until the papyrus is published.

Destruction of mummy masks

The process that is used to obtain the papyri, which involves the destruction of the mummy masks, has also generated debate. For instance, archaeologist Paul Barford, who writes about collecting and heritage issues, has written a scathing blog post criticizing the work on the gospel.

Roberta Mazza, a lecturer in Classics and Ancient History at the University of Manchester, has blogged her concerns about the text as has Brice Jones, a doctoral candidate in religion at Concordia University.

When the texts are published the debate is likely to move beyond the blogosphere and into mainstream media and scholarly journals.

Biblical clues

Although the first-century gospel fragment is small, the text will provide clues as to whether the Gospel of Mark changed over time, Evans said.

His own research is focused on analyzing the mummy mask texts, to try to determine how long people held onto them before disposing or reusing them. This can yield valuable information about how biblical texts were copied over time.

"We have every reason to believe that the original writings and their earliest copies would have been in circulation for a hundred years in most cases — in some cases much longer, even 200 years," he said.

This means that "a scribe making a copy of a script in the third century could actually have at his disposal (the) first-century originals, or first-century copies, as well as second-century copies."

Set to publish

Evans said that the research team will publish the first volume of texts obtained through the mummy masks and cartonnage later this year. It will include the gospel fragment that the researchers believe dates back to the first century.

The team originally hoped the volume would be published in 2013 or 2014, but the date had to be moved back to 2015. Evans said he is uncertain why the book's publication was delayed, but the team has made use of the extra time to conduct further studies into the first-century gospel. "The benefit of the delay is that when it comes out, there will be additional information about it and other related texts."

Follow LiveScience @livescience, Facebook & Google+. Originally published on Live Science.

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DALLAS (Reuters) - A collection of Abraham Lincoln memorabilia, including a lock of the 16th U.S president's hair, will be up for auction in Dallas on Saturday, months before the United States marks 150 years since the end of the Civil War and Lincoln's assassination.

The collection of more than 300 items, with a combined estimated value of about $400,000, belonged to a Fort Worth history buff and is considered to be one of the best private Lincoln collections known to exist, according to Heritage Auction officials.

The late Fort Worth art gallery owner Donald Dow built the collection over five decades, beginning in 1963 with the purchase of a box of books, according to his son Greg Dow, who is selling the collection. The elder Dow died in 2009.

"He started collecting because of his interest in the Civil War and military history," Greg Dow said. "But then he became interested in Lincoln and the assassination."

Lincoln was shot on April 14, 1865, in Washington by John Wilkes Booth, a famous actor and supporter of the Confederacy. He died the next day.

Highlights of the collection include a fragment of a letter Lincoln wrote to a Baltimore attorney in 1862, containing a rare admission that Civil War was not going well for the north but rejecting surrender. The fragment is projected to sell for about $25,000.

Papers endorsed by Lincoln arranging a prisoner swap between a Union soldier in Confederate custody and the son of Confederate General Robert E. Lee, who was being held by the Union, is estimated to sell for $10,000.

The items up for auction include the arrest warrant for Booth, estimated to sell for $4,000, and two eyewitness accounts of the assassination, expected to fetch $6,000 and $8,000.

Greg Dow said the time is right for him to sell the collection.

"I want other collectors to have a chance to enjoy it," Dow said.

(Reporting by Marice Richter; Editing by David Bailey and Mohammad Zargham)

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Twitter only lets you see a portion of your tweet history, but there's an easy way to get a copy of everything.

You can request to download your Twitter archive, which contains a searchable collection of every tweet (and retweet) you've ever made since first making your account.

Here's how to request your own free Twitter archive.

First, head on over to Twitter, click on your avatar in the upper-right-hand corner, and select Settings.

Next, scroll to the bottom of the page where you'll see a big button that says Request your archive.

Click Request your archive, and you're all set! It might take a while, but Twitter will email you a download link of your entire tweet history, which you can search through using keywords, hashtags, date, and @ usernames.

You can read more about what you can do with your Twitter archive here.

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Between 1939 and 1945, more than 10,000 people worked in Bletchley Park, the headquarters of the UK Government Code and Cypher School, tasked with breaking Nazi codes during War World II.

According to historians, the work done at Bletchley Park — now the subject of an Oscar-nominated movie starring Benedict Cumberbatch as British mathematician and codebreaker Alan Turing — shortened the war by two years and saved countless of lives.

It was here where a team of British engineers decoded Enigma, Germany's secret transmission machine, making it possible for the Allies to follow the enemy's moves.

Soon after the war ended in 1945 the facilities were dismantled, and the work done at Bletchley was made confidential.

Most of the devices built there to decode Nazi messages were destroyed. Most of the staff members returned to their daily life and faced serious consequences if they revealed what they had done during the war.

Bletchley Park's secret lasted three decades, while the site was transformed into a training school for members of Government Communications Headquarters, the British intelligence agency that remains in operation.

Only in 1974, when former MI6 officer Frederick Winterbotham published his book "The Ultra Secret," did the public learn about the site's critical role in history.

Many of the people who had worked at Bletchley were shocked. They had never been able to talk about the Park. They couldn't even tell their family. 

Lady Marion Body is one of the those people. She worked on Japanese codes during the war and is among more than 40 women featured in the new book "The Debs Of Bletchley Park" by author Michael Smith.

On a visit to Bletchley last week for a press launch of the book, Body, who sat on a panel with six other women, said that after she left the Park she worked as a secretary in the House of Commons. In 1959, she married Tory MP Richard Body. 

Body's husband was the first to tell her the secret was out. Here's how she recalls that moment:

I remember we could never speak about it and I had never done. One night, though, my husband had gone down to London for work and he had seen that book at Hatchards [a prominent British bookseller]. So he bought a copy and came back home with it, and that night I was sitting in the living room, and he came through the door and dropped the book on the desk in front of me and said: "Well, now will you tell me what you did during the war?"
And I just said: "No!"

Most of Bletchley Park is now a museum dedicated to educating the public about the codebreaking activities that went on there during World War II.

You can read more about Bletchley Park in Michael Smith's book "The Debs Of Bletchley Park."

NOW WATCH: How To Make Your Own Custom Charts In Excel

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In 1983, The Metropolitan Museum of Art bought a 52-card deck of South Netherlandish playing cards.

The cards dated from the 15th century and were in incredible condition — but they were almost lost to history.

An Amsterdam antiques dealer was sold the pack back in the ‘70s for $2,800. They were said to be a “unique” pack of tarot cards from the “16th century,” according to the Paris auction house that sold them.

But the dealer who bought the deck was skeptical, according to a The Day article published in 1983. He thought they might be even older. 

After five years of research, he was able to successfully date the cards to between 1465 and 1480 thanks to the style of the paintings, watermarks on the pasteboard, as well as the costumes and hairdos worn by the Burgundian court figures on the cards.

The shoes, hairstyles, and clothing worn by the kings and queens were going out of style by 1480. The watermarks were also common in Southern Flanders and the Netherlands from 1466 to 1479, according to The Day. 

The dates were confirmed by the Central Laboratory for Objects of Art and Science in Amsterdam which dated the paints used to the 15th Century. 

All of this digging and research paid off. In 1983, the Met bought the pack for $143,000.

It is now accepted that this is the oldest known full deck of playing cards in the world.

The cards themselves are also very interesting. Instead of the suits we know today, the four card categories are based on hunting gear, including hunting horns, dog collars, hound tethers, and game nooses. 

This was not uncommon given that many countries had their own suit symbols. Playing cards were introduced to Europe through the Mameluke Empire in Egypt after originating in China. The Mameluke suits were goblets, gold coins, swords, and polo sticks. Italy and Spain transformed them into batons/staves, swords, cups, and coins. German card makers had acorns, leaves, hearts, and bells. The French were the ones to simplify the shapes and make them the clover, "pike-heads" (a type of weapon), hearts, and paving tiles. 

The English used the simplified French shapes, but called the pike-heads "spades" and the paving tiles "diamonds."

Mass-producing and printing playing cards had still not become the norm, so these cards were drawn free-hand with pen and ink with gold and silver later applied. Because they are in such good condition, it’s assumed the cards were rarely touched.

You can currently view the cards at The Met's Cloisters museum in New York City.

SEE ALSO: Meet The American Poker Exiles Who Gamble All Day And Party All Night In Playa Del Carmen

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It can be hard for us to see sometimes how history relates to our own lives.

There don’t seem to be many similarities between the world today and the world that we read about in our history books.

Our ancestors faced different problems with different tools than we do today.

Still, one thing remains the same: people. For all that has changed in the world, human nature remains remarkably much like it always has been.

Whether you’re leading a nation, an army, or just a company, office, or team, some of the same principles apply.

Here are just a few of the lessons we can learn from the successes (and failures) of great leaders throughout history.

1. Julius Caesar: Understand How Your Subordinates Feel

Caesar was undoubtedly a great leader. His military victories made Rome one of the largest empires in history, and his political leadership made it one of the most prosperous.

Unfortunately, Caesar neglected to pay enough attention to those serving under him, namely the Senate. He constantly ignored the Senate’s wishes as he grabbed dictatorial power until even his friend Brutus was willing to kill him.

Corporate leaders today probably don’t risk assassination, but they can still be “sacked” like one of the armies that Caesar faced. Failure to listen to employees still has significant consequences.

If employees don’t feel like you’re listening to them or respecting their positions, they may choose to ignore your requests, go over your head to your boss, or even quit.

2. Winston Churchill: Words Have Power

It may be sacrilege to say in some circles, but in many respects, Winston Churchill was not that impressive a leader. He did not always have a great military mind, as evidenced by the disastrous Gallipoli invasion he planned in World War I.

His leadership on domestic issues was so poor at times that the citizens of the UK. voted him out of office as soon as World War II ended.

Still, when it counted the most, Churchill lead Great Britain to stand against the monolithic German war machine, due in no small part to Churchill’s inspiring rhetoric. Everyone predicted that a sustained bombing raid such as the German Blitz would totally demoralize a civilian population, but emboldened by Churchill’s words, the people of London carried on with the war effort.

There may not be a need for Churchill levels of rhetoric in the office, but well placed words of encouragement can do wonders for employee morale.

3. John F Kennedy: Maintain Your Flexibility

When US spy planes brought reports of nuclear missiles to the White House in 1962, many of JFK’s close advisors advocated for a full military invasion of Cuba. JFK held off on these plans, opting instead for a naval blockade and negotiations with Soviet leaders, all while planning for a possible invasion if these tactics failed.

In the end, the blockade worked, and the US was able to avoid nuclear war. Had JFK opted for military invasion right away, who knows what might have happened.

Be careful of those big decisions that commit you down a certain path. If an employee is causing trouble, look for other ways of resolving that issue before taking the permanent step of firing them. Don’t commit yourself to a strategic path without first evaluating all of the options available to you.

4. Prince William of Orange: Know When To Take Big Risks

Kennedy, as the leader of the most powerful country in the world, had the luxury of biding his time and exploring all his options. In the 16^th century, Prince William had no such luxury as he led the Dutch rebellion against Spain, then the largest and most powerful empire in the world.

Faced with a massive army bearing down on his tiny country, Prince William took a drastic step: he pulled down several dikes and flooded a large portion of the Dutch countryside. The Spanish troops were bogged down, and the Dutch were able to dig in and win the war.

As a leader today, you have to be willing to recognize when you can’t best your competitors using your current strategy. If a larger competitor is beating you on price, you have to find a way to differentiate yourself, even if that means a radical change in strategy.

5. Alexander the Great: Have A Succession Plan

Alexander the Great built one of the largest empires in history in just a few short years, and it fell apart just as quickly. As soon as Alexander died, his generals carved up his empire into pieces.

Every leader wants to build something that lasts, and that means finding someone to take over once you step down. Failure to do so can mean the undoing of your life’s work in just a few short years.

It’s accurate to say that history repeats itself. But it’s just as accurate to say that history is filled with lessons that we can apply to our business as well as personal lives if we look closely and carefully enough. The above stories are truly helpful to business leaders, but history has no shortage of amazing leadership examples.

Other U.S. Presidents such as Abraham Lincoln, English monarchs like Queen Elizabeth I, or even African tribal leaders like Shaka Zulu displayed intelligence, patience, even brutality when they had to. If you become a student of history, what you learn will help as you apply the lessons to your work life.

John Boitnott is a journalist and digital consultant who has worked at TV, newspapers, radio and internet companies in the U.S. for 20 years. He's an advisor at StartupGrind and has written for NBC, Fast Company, Inc. Magazine, Entrepreneur, USAToday, and VentureBeat, among others.

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Long before Chris Kyle penned "American Sniper," Carlos Hathcock was already a legend.

He taught himself to shoot as a boy, as did Alvin York and Audie Murphy before him. He had dreamed of being a US Marine his whole life, and he enlisted in 1959 at just 17 years old.

Hathcock was an excellent sharpshooter by then, winning the Wimbledon Cup shooting championship in 1965, the year before he would deploy to Vietnam and change the face of American warfare forever.

He deployed in 1966 as a military policeman but immediately volunteered for combat and was soon transferred to the 1st Marine Division Sniper Platoon, stationed at Hill 55, South of Da Nang.

This is where Hathcock would earn the nickname "White Feather"— because he always wore a white feather on his bush hat, daring the North Vietnamese to spot him — and where he would achieve his status as the Vietnam War's deadliest sniper in missions that sound as if they were pulled from the pages of Marvel comics.

White Feather Versus The General

Early morning and early evening were Hathcock's favorite times to strike.  This was important when he volunteered for a mission he knew nothing about.

"First light and last light are the best times," he said. "In the morning, they're going out after a good night's rest, smoking, laughing. When they come back in the evenings, they're tired, lollygagging, not paying attention to detail."

He observed this firsthand, at arms reach, when trying to dispatch a North Vietnamese Army (NVA) general officer. For four days and three nights, Hathcock low-crawled inch by inch, a move he called "worming," without food or sleep, more than 1,500 yards to get close to the general. This was the only time he ever removed the feather from his cap.

"Over a time period like that you could forget the strategy, forget the rules and end up dead," he said. "I didn't want anyone dead, so I took the mission myself, figuring I was better than the rest of them, because I was training them."

Hathcock moved to a treeline near the NVA encampment.

"There were two twin .51s next to me," he said. "I started worming on my side to keep my slug trail thin. I could have tripped the patrols that came by." The general stepped out onto a porch and yawned. The general's aide stepped in front of him, and by the time he moved away, the general was down, the bullet went through his heart. Hathcock was 700 yards away.

"I had to get away," Hathcock said. "When I made the shot, everyone ran to the treeline because that's where the cover was." The soldiers searched for the sniper for three days as he made his way back.

They never even saw him.

"Carlos became part of the environment," said Edward Land, Hathcock's commanding officer. "He totally integrated himself into the environment. He had the patience, drive, and courage to do the job. He felt very strongly that he was saving Marine lives."

With 93 confirmed kills — his longest at 2,500 yards — and an estimated 300 more, for Hathcock, it really wasn't about the killing.

"I really didn't like the killing," he once told a reporter. "You'd have to be crazy to enjoy running around the woods, killing people. But if I didn't get the enemy, they were going to kill the kids over there." Saving American lives is something Hathcock took to heart.

'The Best Shot I Ever Made'

"She was a bad woman," Carlos Hathcock once said of the woman known as "Apache.""Normally kill squads would just kill a Marine and take his shoes or whatever, but the Apache was very sadistic. She would do anything to cause pain."

This was the trademark of the female Viet Cong platoon leader. She captured Americans in the area around Hathcock's unit and tortured them without mercy.

"I was in her backyard; she was in mine. I didn't like that," Hathcock said. "It was personal, very personal. She'd been torturing Marines before I got there."

In November 1966, she captured a Marine private and tortured him within earshot of his own unit.

"She tortured him all afternoon, half the next day," Hathcock recalls. "I was by the wire … He walked out, died right by the wire. Apache skinned the private, cut off his eyelids, removed his fingernails, and then castrated him before letting him go. Hathcock attempted to save him, but he was too late.

Hathcock had enough. He set out to kill Apache before she could kill any more Marines. One day, he and his spotter got a chance.

They observed an NVA sniper platoon on the move. At 700 yards in, one of them stepped off the trail, and Hathcock took what he calls the best shot he ever made.

"We were in the midst of switching rifles. We saw them," he remembered. "I saw a group coming, five of them. I saw her squat to pee; that's how I knew it was her. They tried to get her to stop, but she didn't stop. I stopped her. I put one extra in her for good measure."

A 5-Day Engagement

One day during a forward observation mission, Hathcock and his spotter encountered a newly minted company of NVA troops. They had new uniforms but no support and no communications.

"They had the bad luck of coming up against us," he said. "They came right up the middle of the rice paddy. I dumped the officer in front; my observer dumped the one in the back." The last officer started running the opposite direction.

"Running across a rice paddy is not conducive to good health," Hathcock remarked. "You don't run across rice paddies very fast."

According to Hathcock, once a sniper fires three shots, he leaves. With no leaders left, after three shots, the opposing platoon wasn't moving.

"So there was no reason for us to go either," the sniper said. "No one in charge, a bunch of Ho Chi Minh's finest young go-getters, nothing but a bunch of hamburgers out there." Hathcock called artillery at all times through the coming night, with flares going on the whole time. When morning came, the NVA were still there.

"We didn't withdraw; we just moved," Hathcock recalled. "They attacked where we were the day before. That didn't get far either."

White Feather And The M2

Though the practice had been in use since the Korean War, Carlos Hathcock made the use of the M2 .50-caliber machine gun as a long-range sniper weapon a normal practice. He designed a rifle mount, built by Navy Seabees, which allowed him to easily convert the weapon.

"I was sent to see if that would work," He recalled. "We were elevated on a mountain with bad guys all over. I was there three days, observing. On the third day, I zeroed at 1,000 yards, longest 2,500. Here comes the hamburger, came right across the spot where it was zeroed, he bent over to brush his teeth and I let it fly. If he hadn't stood up, it would have gone over his head. But it didn't."

The distance of that shot was 2,460 yards — almost a mile and a half — and it stood as a record until broken in 2002 by Canadian sniper Arron Perry in Afghanistan.

White Feather Versus The Cobra

"If I hadn't gotten him just then," Hathcock remembers, "he would have gotten me."

Many American snipers had a bounty on their heads. These were usually worth one or two thousand dollars. The reward for the sniper with the white feather in his bush cap, however, was worth $30,000.

Like a sequel to the film "Enemy at The Gates," Hathcock became such a thorn in the side of the NVA that they eventually sent their own best sniper to kill him. He was known as the Cobra and would become Hathcock’s most famous encounter in the course of the war.

"He was doing bad things," Hathcock said. "He was sent to get me, which I didn't really appreciate. He killed a gunny outside my hooch. I watched him die. I vowed I would get him some way or another."

That was the plan. The Cobra would kill many Marines around Hill 55 in an attempt to draw Hathcock out of his base.

"I got my partner; we went out we trailed him. He was very cagey, very smart. He was close to being as good as I was … But no way, ain't no way ain't nobody that good." In an interview filmed in the 1990s, Hathcock discussed how close he and his partner came to being a victim of the Cobra.

"I fell over a rotted tree. I made a mistake and he made a shot. He hit my partner's canteen. We thought he'd been hit because we felt the warmness running over his leg. But he'd just shot his canteen dead."

Eventually the team of Hathcock and his partner, John Burke, and the Cobra had switched places.

"We worked around to where he was," Hathcock said. "I took his old spot, he took my old spot, which was bad news for him because he was facing the sun and glinted off the lens of his scope, I saw the glint and shot the glint." White Feather had shot the Cobra just moments before the Cobra would have taken his own shot.

"I was just quicker on the trigger, otherwise he would have killed me," Hathcock said. "I shot right straight through his scope, didn't touch the sides."

With a wry smile, he added: "And it didn't do his eyesight no good either."

In 1969, a vehicle Hathcock was riding in struck a landmine and knocked the Marine unconscious. He came to and pulled seven of his fellow Marines from the burning wreckage. He left Vietnam with burns on over 40% of his body. He received the Silver Star for this action in 1996.

After the mine ended his sniping career, he established the Marine Sniper School at Quantico, teaching Marines how to "get into the bubble," a state of complete concentration. He was in intense pain as he taught at Quantico, and he also suffered from Multiple Sclerosis, the disease that would ultimately kill him — something the NVA could never accomplish.

SEE ALSO: 'American Sniper' Inspiration Chris Kyle Explains How Snipers Change A Battle

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The oldest known snake fossils, dating from 143 million to 167 million years ago, have been uncovered.

Researchers, writing in the journal Nature Communications, say the fossils push back the first record of snakes by 70 million years.

Wile the snakes share recognisable features with modern snakes – including sharp, backward pointing teeth – their overall shape, length and body form still remains unknown.

Using a number of fossilised skull bones, Michael Caldwell in the Faculty of Science at the University of Alberta and colleagues identified four new species of snakes from England, Portugal and the US.

The snakes originated at a time when most other major groups of scaled reptiles were rapidly diversifying and that they existed in different parts of the globe in many different habitats including swamps, ponds, rivers and coastal systems.

“The study explores the idea that evolution within the group called ‘snakes’ is much more complex than previously thought,” says Professor Caldwell. “Importantly, there is now a significant knowledge gap to be bridged by future research as no fossils snakes are known from between 140 to 100 million years ago.”

Here’s one fossil:

The oldest known snake, from Southern England, near Kirtlington, Eophis underwoodi, is known only from very fragmentary remains and was a small individual.

The largest snake, Portugalophis lignites, from coal deposits in Portugal, near Guimarota, was bigger at nearly one metre or more in length.

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Throughout history, trees have withstood the test of time, quite literally. People are born and people die, civilizations rise and fall, but many trees, trees that you see every day, stay where they are, growing and staying firm.

Photographer Beth Moon is fascinated by trees, especially those that have been around the longest and grown the largest. This fascination led her to travel the globe to photograph the world's most impressive and historic trees.

She is interested in documenting such trees in order to preserve their memory and pay homage to their significance.

Standing as the earth’s largest and oldest living monuments, these symbolic trees will take on a greater significance, Moon says in her artist statement, especially when our focus is directed at finding better ways to live with the environment and celebrating the wonders of nature that have survived throughout the centuries.

Her photos have recently been compiled in a book, "Ancient Trees: Portraits of Time," available through Abbeville Press. She shared some of her photos and stories with us.

One of the most popular tourist attractions in Madagascar, the Avenue of the Baobabs, is a dirt road flanked by about 25 Baobab trees, which are only found on the island and which grow to be almost 100 feet tall. The trees along the avenue are thought to be as old as 800 years.

These two Yew Trees, which flank the door to the Church of St. Edward in Stow-on-the-Wold, England, planted sometime in the 18th century, were probably survivors of an avenue of trees that led to the door of the church. They now appear to grow from the building itself.

This tree, known as Rilke's Banyon, grow around a Buddhist temple in Siem Reap, Cambodia. The trees can grow 150 feet or taller, and their roots can work to tear up the ancient stone work of the building as they search for soil.

In 1917, after centuries Ottoman rule, the British marched into Baghdad and conquered the city.

This allied victory over one World War I's Central powers was hailed in a letter by Captain L. W. Jardine as the "the most triumphant piece of strategy … since the war started." 

The British victory over the Ottomans led to Iraq being ruled as a British mandate from the end of the war until the country gained its independence in 1932. The mandatory period was marked by a country-wide insurgency that the British used exceedingly harsh measures to suppress, including the use of aerial bombardments against alleged insurgent villages. 

The British presence in the country still left behind a wealth of archaeological discoveries, as well as photographic material showing what life was like in the the heart of the Middle East nearly 100 years ago. 

Baghdad was a much different city back then. One-third of Baghdad's population was Jewish before World War I and by mid-century the city had a population of barely more than a half-million people. Today, Shi'ite Muslims dominate the city's demographics, and Baghdad had a population of over 5.5 million.

Baghdad has also turned into perhaps the most violent of the world's mega-cities thanks to a recent history that includes Saddam Hussein's rule, the US invasion of the country, and the more recent war against ISIS.

But when this footage was taken, that was all decades away.

Below are stills from a British film showing what Baghdad looked like between 1917 and 1920.

After conquering Baghdad, a number of British military officers stayed in the city to oversee operations. Below is Lieutenant-General Sir William R. Marshall.

British troops were heavily augmented in Iraq by the presence of Indian soldiers. 

Daily continued as normal in Baghdad even with the presence of the British. Here, ships sail along the Tigris River.

At the time, bridges connecting the two sides of Baghdad on the Tigris were significantly smaller than the current multi-lane highways that criss-cross the river. 

Iraqi men continued to gather in tea houses on the banks of the Tigris to drink tea and socialize. 

Iraqi men visited street barbers for hair cuts and shaves. 

The full historic video is below. 

H/t Joel Wing

SEE ALSO: These amazing pictures show what Iraq was like before the country's decades of chaos

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Archaeologists are excavating the vessel that served as the flagship of the pirate Blackbeard, and the medical equipment they have recovered from the shipwreck suggests the notorious buccaneer had to toil to keep his crew healthy.

Blackbeard is the most famous pirate who ever lived. His real name was Edward Teach (or possibly Thatch), and his flagship, the Queen Anne's Revenge, was formerly a French slave vessel named La Concorde de Nantes that Blackbeard captured in November 1717.

Blackbeard was able to capture this ship easily because much of its crew was either sick or dead due to disease.

A few months into 1718, the Queen Anne's Revenge ran aground on a sandbar at Topsail Inlet in North Carolina. Blackbeard abandoned much of his crew at that point, leaving the site with a select group of men and most of the plunder. He was killed in battle later that year.

The wreck of the Queen Anne's Revenge was rediscovered in 1996 and has been under excavation by the Queen Anne's Revenge Project. Archaeologists have recovered many artifacts, including a number of medical instruments. These artifacts, combined with historical records, paint a picture of a pirate captain who tried to keep his crew in fighting shape.

"Treating the sick and injured of a sea-bound community on shipboard was challenging in the best of times," Linda Carnes-McNaughton, an archaeologist and curator with the Department of Defense who volunteers her time on the excavation project, wrote in a paper she presented recently at the Society for Historical Archaeology annual meeting. [Photos: The Medical Instruments Found on Blackbeard's Ship]

The people on a ship like Blackbeard's would have had to contend with many conditions, including "chronic and periodic illnesses, wounds, amputations, toothaches, burns and other indescribable maladies," Carnes-McNaughton said.

Blackbeard's surgeons

In fact, maintaining the crew's health was so important that when Blackbeard turned the Queen Anne's Revenge into his flagship, he released most of the French crew members he had captured, but he forced the ship's three surgeons to stay, along with a few other specialized workers like carpenters and the cook, Carnes-McNaughton said.

She noted, however, that "The Sea-Man's Vade Mecum" of 1707,which contained the rules that seafarers were supposed to follow, had a provision stating that surgeons could not leave their ship until its voyage was complete.

Carnes-McNaughton investigated both the La Concorde de Nantes' crew muster, which is the document that lists crew members' names and salaries, as well as court records to learn more about the surgeons Blackbeard captured.

The ship's muster indicates that La Concorde de Nantes' surgeon major was a man named Jean Dubou (or Dubois), from St. Etienne. Before he was captured by Blackbeard, Dubou was being paid 50 livres for his work on the ship's voyage. The second surgeon was Marc Bourgneuf of La Rochelle, who was paid 30 livres for the voyage.

The third surgeon was Claude Deshayes, who was listed as a gunsmith on the muster and paid 22 livres for his work. The muster also names a surgeon's aide, Nicholas Gautrain, who was paid 12 livres. Although he is named on the muster, Gautrain is not mentioned in court records.

Medical equipment

When archaeologists excavated the Queen Anne's Revenge they found a number of medical instruments, some with marks that indicate they were manufactured in France. Carnes-McNaughton said that Dubou and his aides were required to supply their own medical equipment, and Blackbeard likely captured this equipment when he captured the surgeons. [The 7 Most Mysterious Archaeological Finds on Earth]

Among the finds was a urethral syringe that chemical analysis indicates originally contained mercury. Carnes-McNaughton told Live Science that this would have been used to treat syphilis, a sexually transmitted disease. "Eventually the mercury kills you," she said, explaining that the patient could suffer mercury poisoning.

Archaeologists also found the remains of two pump clysters. These would have been used to pump fluid into the rectum, allowing it to be absorbed quickly, Carnes-McNaughton said. It's not clear exactly why this would have been done, but there are plans to analyze the clysters to find out what material they contained before the ship was wrecked.

An instrument called a porringer was also found, which may have been used in bloodletting treatments, Carnes-McNaughton said. People in the early 18^th century believed that bloodletting could cure some conditions and a modern-day form of the treatment is still used for a few conditions.

Archaeologists also found a cast brass mortar and pestle and two sets of nesting weights, devices that would have been used in preparing medicine. The remains of galley pots were also found that would have been used to store balms, salves and other potions.

Some items were found that could have been used medically or non-medically, Carnes-McNaughton said, including a silver needle and the remains of scissors, which could have been handy during surgeries. Two pairs of brass set screws were also found that may have been used in a tourniquet, a device that limits bleeding during amputations.

Carnes-McNaughton said she is going to compare the medical equipment from Queen Anne's Revenge to those found on other wrecks.

Getting medicine

But although the captured surgeons had medical equipment, Blackbeard would have still needed a supply of medicine to treat his crew. He got some in 1718, after he spent a week blockading the port of Charleston, South Carolina. Blackbeard captured ships that tried to get past him, holding their crew and passengers hostage.

When it came time to parley with the governor of South Carolina, a chest of medicine was demanded.

Blackbeard threatened that he "would murder all their prisoners, send up their heads to the governor, and set the ships they had taken on fire," if the governor didn't deliver the medicine chest, writes Capt. Charles Johnson, who published an account of Blackbeard in 1724.

The governor promptly complied and the prisoners were released.

In the end, Blackbeard's efforts to keep up his crew's health didn't change the pirate's own fate when he was hunted down in November 1718 by the Royal Navy.

Blackbeard was in good enough shape that he is said to have put up a terrific final fight while trying to board an enemy ship.

"He stood his ground and fought with great fury, till he received five and 20 wounds, and five of them by shot," Johnson wrote. "At length, as he was cocking another pistol, having fired several before, [when] he fell down dead."

Follow Live Science @livescience, Facebook& Google+.Originally published on Live Science.

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Want to know why we use fossil fuels to power our buildings and cars? How the US came to be the "leader of the free world"? How we transitioned from floating single-celled organisms to walking, talking humans?

Then you should read eight books, says Hayden Planetarium director, Cosmos narrator, StarTalk host, and author Neil deGrasse Tyson.

Each of the books on Tyson's must-read list, which he first described during a Reddit Ask-Me-Anything in 2011, contain a powerful lesson about how the world as we know it came to be.

Here are Tyson's eight selections, along with a one-liner he gave during his AMA on the importance of each book:

1. "The Bible," to learn that it's easier to be told by others what to think and believe than it is to think for yourself."

2. "The System of the World," by Isaac Newton, "to learn that the universe is a knowable place."

3. "On the Origin of Species," by Charles Darwin, "to learn that we have a kinship with all other life on Earth."

4. "Gulliver's Travels," by Jonathan Swift, "to learn, among other satirical lessons, that most of the time humans are yahoos."

5. "The Age of Reason," by Thomas Paine, "to learn that the power of rational thought is the primary source of freedom in the world."

6. "The Wealth of Nations," by Adam Smith, "to learn that capitalism is an economy of greed, a force of nature unto itself."

7. "The Art of War," by Sun Tzu, "to learn that the act of killing fellow humans can be raised to an art."

8. "The Prince," by Machiavelli, "to learn that people not in power will do all they can to acquire it, and people in power will do all they can to keep it."

Beyond these eight, Tyson has a few other must-reads on his list, he recently told The New York Times. These reads are for everyone from newborns to presidents.

To encourage a child's interest in science, for example, he recommends "On the Day You Were Born" by Debra Frasier, which explains how the forces of the Earth work together to make this planet a perfect home for all of us.

"On the day you were born," the book opens, "the Moon pulled on the ocean below, and, wave by wave, a rising tide washed the beaches clean for your footprints."

For a growing child, "The Adventures of Pinocchio" by Carlo Collodi provides the perfect example of "how not to behave," Tyson told The Times.

And when he or she reaches middle or high school, books like "One, Two, Three . . . Infinity" by George Gamow and "Mathematics and the Imagination" by James Newman and Edward Kasner can help show him or her how the world works. Both of these reads, Tyson says, helped transform the fields of math and science "into an intellectual playground."

Adults, too, can benefit spectacularly from a good read. Every American president, says Tyson, should read "Physics for Future Presidents," by Richard A. Muller. The book takes basic physics concepts and applies them to current issues from energy and climate change to terrorism.

But, he adds, "I'd like to believe that the president of the United States, the most powerful person in the world, has time to read more than one book," Tyson tells The Times.

A good reminder for us all to get reading.

UP NEXT: Neil deGrasse Tyson's 'most astounding fact about the universe' may bring you to tears

SEE ALSO: Neil deGrasse Tyson tells us why 'Star Trek' is so much better than 'Star Wars'

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The US officially adopted the federal income tax 102 years ago today.

The Supreme Court hadruled in 1895 that the income tax violated Article I of the Constitution, so the amendment was necessary to empower the federal government to impose the income tax.

But the story of the income tax goes back much further than 1913, culminating in some sneaky political maneuvering.

Conservatives — who aren't the biggest fans of the income tax — actually introduced the 16th amendment. They figured it would never pass hoped its introduction would stop liberals from pushing for an income tax as part of a tariff, according to the National Archives and Records Administration.

That backfired, of course.

Income taxes were initially a temporary provision. Congress passed the Revenue Act of 1861, which included a tax on personal income to help pay for the hefty expenses of the Civil War. Without proper enforcement, however, it raised little money. In turn, the Internal Revenue Act of 1862 created the Internal Revenue Service to solve that problem.

The new law levied a 3% tax on individual incomes between $600 and $10,000 (between about $14,000 and $230,000 today) and 5% on greater than that. The act reportedly produced about $55 million in government revenue. 

Ten years later, however, long after the war had ended, the Grant administration repealed most of the "emergency" taxes, including the income tax.

Then, in 1894, the Wilson-Gorman Tariff Act revived the income tax, imposing a 2% tax on incomes over $4,000. President Grover Cleveland, in cahoots with Congressman William Wilson (D-West Virginia), originally intended the law to lower tariffs, according to The New York Times. After its introduction, however, the Senate drastically altered it, turning the bill into a high-tariff one. 

While Cleveland refused to sign the act, he didn't veto it either, still considering the law better than its predecessor, the McKinley Tariff. 

The next year, however, the Supreme Court ruled the income tax provision of the Wilson-Gorman Tariff was a direct tax, and as such, violated Article I of the Constitution, which stated taxes had to be levied in proportion to a state's population. That didn't stop progressives from trying to once again attach an income tax to a tariff bill though.

For their part, conservatives wanted to put the kibosh on progressives' efforts to pass an income tax. Conservatives thought an amendment to allow an income tax would never pass since three-fourths of states have to ratify an amendment for it to become part of the Constitution. So conservatives introduced the amendment, hoping to kill progressives efforts to pass an income tax as part of a tariff. Much to conservatives' dismay, state after state hopped on board.

The 16th Amendment, which established an official, federal income tax, was ratified on Feb. 3 and went into effect on Feb. 25 1913. 

h/t Constitution Daily

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In today's post-9/11 world, the threat of terrorism looms large for many people.

These fears are fueled by a 24-hour news cycle that sheds light on horrors throughout the world, despite that violence has actually declined.

This dichotomy is one of the reasons that Facebook CEO Mark Zuckerberg chose Harvard psychologist Steven Pinker's "The Better Angels of Our Nature: Why Violence Has Declined" as the second selection in his "A Year in Books" book club.

Zuckerberg writes on his personal Facebook page that, "It's a timely book about how and why violence has steadily decreased throughout our history, and how we can continue this trend."

Bill Gates is another prominent fan of this data-rich, 800-page book. In a 2012 blog post, he wrote that it "stands out as one of the most important books I've read — not just this year, but ever."

Pinker tells Business Insider he wanted to give readers "a different appreciation of the world from day-to-day journalism. Since there will always be incidents to fill the news, if you get your appreciation of the world from the news, you'll get a systematically distorted picture."

"By virtually every measure, the world has become less violent," says Pinker. "Of course that doesn't mean violence has disappeared, just that it occurs at lesser rates than it used to."

To fully appreciate Pinker's book, you'll need to spend a considerable amount of time with it. Here's a breakdown of its main points.

There are six major trends in human history's retreat from violence.

1. The Pacification Process

Around 5,000 years ago, humans made the transition "from the anarchy of the hunting, gathering, and horticultural societies in which our species spent most of its evolutionary history to the first agricultural civilizations with cities and governments," Pinker writes.

2. The Civilizing Process

Between the late Middle Ages and the 20th century, homicide reduced drastically in societies, which sociologist Norbert Elias says is best seen in European countries, in which there was "the consolidation of a patchwork of feudal territories into large kingdoms with centralized authority and an infrastructure of commerce," Pinker says.

3. Humanitarian Revolution

Best understood in the Western world as starting with the Age of Reason and the Enlightenment and lasting hundreds of years, it was the first time there were movements to abolish sanctioned forms of violence like "despotism, slavery, dueling, judicial torture, superstitious killing, sadistic punishment, and cruelty to animals."

4. The Long Peace

At the end of World War II, the world's most powerful and developed countries stopped waging war with each other.

5. The New Peace

Pinker writes that some readers will be surprised to learn that "since the end of the Cold War in 1989, organized conflicts of all kinds — civil wars, genocides, repression by autocratic governments, and terrorist attacks — have declined throughout the world."

6. The Rights Revolutions

Since the late 1950s, there has a been "a growing revulsion against aggression on smaller scales," empowered by movements for "civil rights, women's rights, children's rights, gay rights, and animal rights."

Humans are neither innately good nor innately evil, but have biological triggers that can orient them toward aggression or cooperation.

Pinker's 2002 book "The Blank Slate" argues that the evolution of the brain disproves the "blank slate" theory that lends total moral authority to nurture over nature. In "The Better Angels of Our Nature," Pinker categorizes "five inner demons" as psychological systems that can be triggered to release aggression, along with "four better angels" as motives that can bring humans toward cooperation and altruism.

Pinker clarifies that even though many people have an implicit belief that aggression is something built up with the need to be released, "Nothing could be further from a contemporary scientific understanding of the psychology of violence," he writes.

There are five external factors that favor our "better angels" and have made humans less violent.

1. The Leviathan

A government and legal system with authority on the legitimate use of force compels individuals to refrain from acting on aggressive urges.

2. Commerce

"[A]s technological progress allows the exchange of goods and ideas over longer distances and among larger groups of trading partners, other people become more valuable alive than dead, and they are less likely to become targets of demonization and dehumanization," Pinker writes.

3. Feminization

Pinker argues that "since violence is largely a male pastime, cultures that empower women tend to move away from the glorification of violence and are less likely to breed dangerous subcultures of rootless young men."

4. Cosmopolitanism

Literacy, mobility, and mass media can allow individuals to empathize with people unlike themselves, Pinker says.

5. The escalator of reason

When humans increasingly prioritize reason, they can recognize the "futility of cycles of violence" and selfishness, and can "reframe violence as a problem to be solved rather than a contest to be won," he writes.

Zuckerberg says that he wants people to read Pinker's book because "recent events might make it seem like violence and terrorism are more common than ever, so it's worth understanding that all violence — even terrorism — is actually decreasing over time. If we understand how we are achieving this, we can continue our path towards peace."

"A Year in Books" so far:

• "The End of Power: From Boardrooms to Battlefields and Churches to States, Why Being In Charge Isn’t What It Used to Be" by Moisés Naím
• "The Better Angels of Our Nature: Why Violence Has Declined" by Steven Pinker
• "Gang Leader for a Day: A Rogue Sociologist Takes to the Streets" by Sudhir Venkatesh

SEE ALSO: Why Mark Zuckerberg is reading a book called 'Gang Leader for a Day'

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You know dining habits have shifted dramatically when Iowa City’s Sushi Kicchin boasts a four-and-a-half star Yelp review.

From pinwheel-shaped rainbow rolls to minimalist slices of toro pressed gently on rice, the idea of serving raw fish has spread far and wide, prepared by everyone from trained sushi masters, to commissary workers who keep your local Duane Reade stocked with California rolls.

As pervasive as it is today, sushi didn’t come into existence until the 20th century; eating raw fish over rice only became a practice once refrigeration was invented in 1913.

The most primitive form of sushi would probably send most contemporary eaters running. “It smelled really bad,” says Yoko Isassi, an L.A.-based Japanese cooking instructor whose done extensive research on history of sushi. “Today’s sushi is a very new concept.”

Born in the Gifu prefecture in central Japan, Isassi initially immigrated to America to become an architect. She eventually gave up on that to teach Japanese cooking classes, informed by her travels in her home country.

“Back then, it was just pickled fish and rice, which would be left in a barrel for a year and weighed down by a heavy stone,” she explains. Called nare-sushi, the original form of sushi can be traced back to Southeast Asia in 3-5 century B.C., when people first began the practice of fermenting fish with salt and rice.

“There are a lot of similarities between the ethnic tribes of southeast China and the Japanese people,” Isassi says. “Because of this, there’s speculation that a certain chunk of people from southern China emigrated to Japan and heavily influenced the food culture.”

The product that we see at our local sushi bars has undergone various stages of transformation to arrive where it is today. “Each new generation of sushi reflects the attitudes of its time,” says Isassi.

Why, then, were prime cuts like fatty tuna initially discarded and used as fertilizer? And how did vinegar come into the equation? To answer these questions—and learn about how rampant wildfires played a crucial role in sushi’s development—we asked raw-fish expert Yoko Isassi to give us a generation-by-generation history lesson on the art of sushi making.

FIRST GENERATION: NARE-SUSHI

Basically: Barrel-fermented fish with rice. Rice is scraped off. Only the fish is eaten.
Originated: 3rd century B.C. in Southern China
Preparation time: 1 year
Where to get it today: Regions near Lake Biwa

The very first generation of sushi involved an intensive fermentation process.“After rainy seasons in southern China and parts of Japan, the lakes would flood and the fish would get caught in the rice fields,” Isassi says. “Pickling was a way to preserve the excess fish.”

While documentation of this practice is sparse, Isassi notes that the character for pickled fish with salt, si 鮨, appeared in the Chinese dictionary as early as the 3rd to 5th century B.C. Then in the 2nd century A.D., the character sa 鮓 appeared, which translates to pickled fish with salt and rice. This created the foundation for sushi. “The fish of choice was most commonly carp,” says Isassi. “They would take the fish, gut it, rub it with salt, and pickle it in a wooden barrel for a few months. Then after that, they would scrape the salt off and then stuff the belly with rice.”

Dozens of rice-stuffed fish would be packed in a wooden barrel and then weighed down with a heavy stone. The fish would sit for a year before being cracked open for consumption. “No one ate the rice back then. It was just the fish.” This practice spread to Japan but eventually went out of vogue in China after northern nomadic tribes invaded and ruled the area. “Even today, this style can still be found in some parts of Yunnan and northern Thailand,” Isassi says.

SECOND GENERATION: HAN-NARE SUSHI

Basically: Barrel-fermented fish with rice
Originated: Before  the14th century in Japan
Preparation time: 1-4 weeks
Where to get it today: Wakayama

The only difference between the process of making han-nare sushi and thenare-sushi is the fermentation time. “Instead of a year, the barrels would be cracked open within the month,” Isassi says. 

And instead of discarding the rice, people would actually eat it with the fish. “The rice had a sour taste to it because of the presence of lactic acid,” she says. “At this time, people really began to appreciate the taste of it, most likely because the vinegar industry had exploded in Japan in the 13th century.”

THIRD GENERATION: HAYA-NARE SUSHI

Summary: Box-pressed cured fish over vinegar-seasoned rice
Originated: 14th-18th century Japan
Preparation time: Hours to a couple of days
Where to get it today: Osaka, Nara, Kyoto, Toyama

By the 18th century, the process of sushi-making shortened dramatically, taking only a couple of days compared to the yearlong process of prior generations. “Instead of waiting for lactic acid to naturally develop on the rice, people started to add vinegar to the rice to mimic the sourness,” Isassi says. The rice would be packed underneath slices of cured or cooked fish, then pressed with a wooden box for hours—sometimes days—at a time. “Fish still had to be treated,” Isassi notes. “They did it either through pickling, curing, or just simply cooking it.”

Every prefecture developed its own style of box-pressed sushi. “In Kansai, for example, they used kombu (kelp) to cook the rice, and seasoned it with vinegar and sugar,” she says. “In Nara, people used persimmon leaves to wrap the sushi. In Toyama, they used bamboo leaves. Adding sugar to the rice was a common practice to preserve the longevity of the sushi.”

FOURTH GENERATION: EDO-MAE SUSHI

Basically: Pre-cured fish over vinegar-seasoned rice. Packed with hands.
Originated: 19th century to early 20th century in Edo (modern-day Tokyo)
Preparation time: Within a few hours to half a day
Where to get it today: Tokyo

The fourth generation of sushi developed in modern-day Tokyo. “Because Edo [the former name of Tokyo] was really dense, they often dealt with fires,” Isassi explains. “They’d appear every several years. To extinguish the flames and stop them from spreading, they would have to knock down all the houses.”As a result, hordes of blue-collar workers flocked to the street to help with the rebuilding process. “That’s how the culture of street food in Japan started,” Isassi says. “They would use fish from the Edo bay, quickly cure it, and serve it over packed vinegar-seasoned rice.”

Isassi notes that only certain fish were consumed. “They used to discard fatty tuna on the fields for fertilizers. There just wasn’t a way to properly treat these cuts. Remember, there wasn’t refrigeration.” The first varieties of Edo-maesushi were also three times bigger than modern-day sushi slices. “It was basically a gigantic rice ball with fish. As time went on, the portion sizes got smaller and smaller,” says Isassi.

FIFTH GENERATION SUSHI: MODERN-DAY SUSHI

Basically: Raw fish over rice, inside-out rolls, conveyer belt sushi
Originated: 20th century
Preparation time: Instant
Where to get it today: Global

The invention of refrigeration in the 20th century changed the sushi scene forever. This is when raw fish slices over rice came into vogue, and sushi morphed from a humble foodstuff into a luxury experience. “In Japan, eating sushi is usually reserved for special occasion meals,” Isassi says. “My family and I rarely went out for it because it was expensive.”

Sushi soon began to spread globally and in the 1960s, the United States came up with its own rendition: the inside-out roll, which was invented in Los Angeles in the 1960s, followed by conveyor-belt sushi, which peaked in the 1980s.

More from First We Feast:

Amazing Sushi Art From Tokyo Chef Tama-Chan

Stop Eating Sushi Like a Noob (Video)

Watch This Incredible Japanese Chef Make Micro-Sized Sushi (Video)

Whole Fish Sushi Rolls Are a Thing

Andy Milonakis Goes on Rant About L.A. Sushi, Thinks New York’s Sushi Scene is Far Superior

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The dollar in your pocket has a hidden history. 

Behind President Washington's steady gaze lies an inheritance of struggle, exploration, and wealth — touching on four continents and five centuries. 

It all began in the 1500s in the Bohemia, a powerful kingdom that ruled much of the present-day Czech Republic. 

Central Europe was in the middle of a silver boon. Thanks to silver discovered in Germany, Austria, and Czech, the region was making a big switch in currency: Instead of using tiny gold coins to do business, merchants started using larger silver coins of an equivalent value. 

The best of these coins came from the Bohemian town of St Joachimsthal, situated on today's Czech-German border. 

"St Joachimsthal was hugely productive,"reports the British Museum, "and gave this type of coin a new name: the thaler," short for Joachimsthaler. 

This coin was a big deal, io9 reports. The 'thaler' started to be used a byword for coins of a similar quality, kind of like how a 'Frankfurter' is a byword for a class of delicious sausages. 

The Bohemian coin was was so popular that other kingdoms and states started making their own 'thaler' equivalent. You can see it in some of more recent currencies: the Dutch daalder, Slovenian tolar, the Eritrean tallero, and put into English, the dollar.   

Around that same time, Spain was colonizing the New World. They found an insane amount of silver, so much that the Spanish-controlled lands of Boliva, Peru, and Mexico would create an estimated 85% of the world's silver between 1500 and 1800. 

From those mines, Spain started minting a new coin, the "peso de ocho," or piece of eight, which would be used in foreign trade around the world. After the Spanish established a foothold in the Philippine city of Manila, the coin started circulating through Asia — the Japanese Yen and Chinese Yuan mean 'round object' in their respective languages, and it's a nod to the massively produced Spanish currency.

In fact, British colonists in North America had a terrible time tracking down official English currency, so much of colonial commerce was done with those same pesos, or as they came to be known for their equivalence to the Bohemian coin, Spanish dollars. 

Then, in 1776, the Colonies declared their independence.

They had to decide on a new currency. They could keep the British pound, or take the name of the currency so many citizens were already using — the dollar.

So the young country exchanged the British Pound Sterling in favor of the new American Dollar.

It was formalized in the Coinage Act of 1792:

DOLLARS OR UNITS — each to be of the value of a Spanish milled dollar as the same is now current, and to contain three hundred and seventy-one grains and four sixteenth parts of a grain of pure, or four hundred and sixteen grains of standard silver.

... the money of account of the United States ... shall be expressed in dollars, or units ... and that all accounts in the public offices and all proceedings in the courts of the United States shall be kept and had in conformity to this regulation.

The story of the dollar, then, goes from Bohemia, to Spain, to Mexico, the American Colonies, to your pocket.

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In a northern section of Hong Kong there once stood one of the most densely populated places on earth.

From the 1950s until 1994, over 33,000 people lived and worked in Kowloon Walled City, a massive complex of 300 interconnected buildings that took up a city block.

Caught between China and the British-run Hong Kong government, the city was essentially lawless, equally known for its opium dens and organized crime as its dentists' offices. 

Photographer Greg Girard spent years investigating and documenting the strange place before it was demolished. Girard collaborated with Ian Lambot, another photographer, on a book about Kowloon, titled "City of Darkness Revisited," available here.

Girard has shared a number of photos from the project here, and you can check out the rest at the book's website.

Kowloon Walled City was a densely populated, ungoverned settlement in Kowloon, an area in northern Hong Kong. What began as a Chinese military fort evolved into a squatters' village comprising a mass of 300 interconnected high-rise buildings.

The city began as a low-rise squatter village during the early 20th century. After World War II, Hong Kong experienced a massive influx of Chinese immigrants. This led to a lack of housing in the city. In response, entrepreneurs and those with "squatter's rights" in Kowloon built high rise buildings on the space to capitalize on the housing demand.

At its peak, more than 33,000 people lived in the 6.4-acre city. It was considered by many to be the most densely populated place on earth.

While not thought to be directly related to modern Valentine’s Day traditions, the beginnings of celebrating love (of a sort) in February date back to the Romans.

The feast of Lupercalia was a pagan fertility and health festival, observed from February 13th through the 15th, that was celebrated at least as far back as 44 BCE (the year Julius Caesar was assassinated).

Some historians believe it goes back even further, though with possibly a different name.

Connected to the Roman god Lupercus, (the equivalent to the Greek god Pan), the festival was originally supposed to be about shepherds and bringing health and fertility to their sheep and cows.

When it became more ingrained into Roman culture, it additionally celebrated Lupa (also another possible reason it is named what it is), the she-wolf who nursed the legendary founders of Rome, Romulus and Remus, to health.

Religious offerings happened at the cave on Palatine Hill, the place where Rome was thought to be founded.

The ceremonies were filled with animal sacrifices, the wearing of goat skins, and nudity. Priests would lead sacrifices of goats and young dogs, animals who were thought to have a "strong sexual instinct."

Afterwards, a feast would occur with lots of wine flowing.

When everyone was fat and happy, the men would shed their clothes, drape the goat skins from the earlier sacrifice on their naked bodies, and run around the city striking naked women.

As Plutarch described:

Lupercalia, of which many write that it was anciently celebrated by shepherds, and has also some connection with the Arcadian Lycaea. At this time many of the noble youths and of the magistrates run up and down through the city naked, for sport and laughter striking those they meet with shaggy thongs. And many women of rank also purposely get in their way, and like children at school present their hands to be struck, believing that the pregnant will thus be helped in delivery, and the barren to pregnancy.

It has also been speculated that there was match-making that went on during the feast, akin to what people did at festivals during the Middle Ages.

Whether the original feast had it or not, later, young men would draw names of young woman, randomly pairing up one another during the feast. If the pairing was agreeable, a marriage could potentially be arranged. If not, well, they broke up.

As the years went by, the feast of Lupercalia was celebrated less by the higher class and the aristocratic and enjoyed almost exclusively by the working class. In fact, the wealthy would insult one another by telling each other to attend the feast of Lupercalia.

In the fifth century, Pope Hilary tried to get the festival banned due to it being a pagan ritual and unchristian. At the end of the fifth century (appx 496 AD), Pope Gelasius I did end up banning it.

In a long letter sent to all Roman nobility who wanted the festival to continue, he stated, "If you assert that this rite has salutary force, celebrate it yourselves in the ancestral fashion; run nude yourselves that you may properly carry out the mockery."

Pope Gelasius also established a much more Christian celebration and declared it would be honored on February 14th – a feast in which St. Valentine would be the patron saint.

Between the second and eighth centuries, the name Valentine was actually rather common since it translated from Latin meaning "strong or powerful."

Scattered through the Christian religion over the last two thousand years, there have been a dozen different Valentines who have drawn mention, including a Pope (during the 9th century, but was only Pope for two months).

It seems the Valentine that Pope Gelasius dedicated a feast to may have been a composite of two or three different men. You see, he never made it clear who exactly he was trying to honor, and even the Catholic Church today isn’t sure.

One of the Valentines lived in the third century and was beheaded under the rule of Emperor Claudius, alleged by some to be because he illegally married Christian couples.

Claudius (as did other Emperors before him) believed that soldiers fought better and were more loyal if they were single and had no wife to return home too. So, he banned soldiers from being married.

Another account speaks of a Valentine being killed in the Roman province of Africa because he wouldn’t give up being Christian in the 4th century. Yet another was the Bishop of Interamna (in Italy) during 3rd century; he was beheaded.

Back to 496 AD: Pope Gelasius I instituted the feast in which St. Valentine would be the patron saint, which some have conjectured was meant as a replacement for Lupercalia. After all, co-opting pagan rituals to turn them Christian has been a time-honored practice of the Catholic Church.

Whatever the motivations, Gelasius’ new feast didn’t really catch on and no such holiday was commonly celebrated in the middle of February for the next thousand years or so, until the 14th century.

(It should also be noted that while Pope Gelasius did ban Lupercalia and proposed a new holiday, it is thought by many historians to be relatively unrelated to modern Valentine’s Day, in that it seems to have had nothing to do with love. For instance, it has been speculated that it was simply a feast of Purification.)

So what about the more recent direct genesis of Valentine’s Day? This began with Geoffrey Chaucer, who is more known as the writer of The Canterbury Tales.

However, he also wrote other things, such as a 700 line poem in 1382 called the "Parliament of Foules," written in honor of the first anniversary of King Richard II of England and Anne of Bohemia’s engagement.

This poem is generally considered to include the first explicit Valentine’s Day / love connection ever written, with one of the lines reading (of course, translated to modern English),

"For this was Saint Valentine’s day, when every bird of every kind that men can imagine comes to this place to choose his mate."

While some scholars believed Chaucer invented the Valentine’s Day / love connection that was previously not mentioned in any writings that have survived to this day, it may well have been that he simply helped popularized the idea.

Around the same time Chaucer was penning this poem, at least three other notable authors (Otton de Grandson, John Gower, and Pardo from Valencia) were also referencing St. Valentine’s Day and the mating of birds in their poems.

Whatever the case, the idea of Valentine’s Day being a day for lovers caught on, with an early Valentine being written by Margery Brewes in 1477 to John Paston, who she called "my right well-beloved Valentine."

Over a century later, Shakespeare was writing about Valentine’s Day in, among other works, Hamlet with this line,

To-morrow is Saint Valentine’s day,
All in the morning betime,
And I a maid at your window,
To be your Valentine.

Fast-forward to around the 18th century and the idea of exchanging love note cards on Valentine’s Day started to become extremely popular in Britain, first hand-made then produced commercially (initially called "Mechanical Valentines").

This tradition of exchanging love notes on Valentine’s Day soon spread to America. Esther A. Howland, whose father ran a large book and stationary store, received a Valentine and decided this would be a great way to make money; so was inspired to begin mass producing these cards in the 1850s in the United States. Others followed suit.

Since then, the holiday has steadily grown to today when it is an absolute marketing and money making machine (second only to Christmas in money spent by consumers).

Further, according to the Greeting Card Association, more than 25% of all cards sent each year are Valentine’s Day cards, about one billion cards each year.

In the 1980s, the diamond industry decided it wanted its cut and began running marketing campaigns promoting Valentine’s Day as a day to give jewelry to show you really loved someone, instead of just sending cards and chocolates; this was obviously a very successful campaign.

So, this year on Valentine’s Day, when you have your hands full of roses, chocolates, and Hallmark Cards for your Valentine, you’ll know who to thank – Pope Gelasius banning a naked, drunk pagan ritual, the beheading of a guy for supposedly marrying people, and Geoffrey Chaucer and his Parliament of Foules.

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Since 2006, photographer Tim Mantoani has captured more than 150 photographers and the iconic images that made them famous in a single shot for his "Behind Photographs" series.

"It was important to step back and understand that cameras didn't make these photos, photographers made these photos," Mantoani told WIRED. "Without these people and their understanding of photography, these moments would not be there for us to understand and appreciate over the course of time."

To create the images Mantoani rented a massive 20x24 Polaroid camera made in the 1970’s to shoot legendary music photographer, Jim Marshall and sports photojournalist, Michael Zagaris. "I asked each of them to bring in a few of their most iconic or favorite shots and I made my first portraits," Mantoani wrote Business Insider.

Here are a few from Mantoani's portraits republished from "Behind Photographs" with permission:

Girl In Afghanistan

Steve McCurry: Peshawar, Pakistan, 1984. I looked for this girl for 17 years and finally found her in 2002. Her name is Sharbat Gula.

Beijing 1989

Jeff Widener: Beijing, 1989. Widener holds his image of the Tank Man confronting a column of tanks in Tiananmen Square during the Tiananmen Square protests.

9/11

Lyle Owerko: New York, 2001. No one knew such beautiful warm day would serve as the backdrop to one of the most painful and confusing events to the heart of mankind. This picture is one small part of such a huge event that ties the threads of thousands of stories and millions of people together.

Brown Bear

Thomas Mangelsen: Brooks Falls Katmai National Park, Alaska, 1988. I pre-visualized this possibility (of an image like this) from watching documentary films about the bears at Katmai and seeing a photograph in Alaska Air Magazine of a group of bears here at the falls.

The Beatles

Harry Benson: New York, 1964. Beatles Manager, Brian Epstein, had just told them they were number one in America and that I was coming with them to New York.

 Ali vs. Liston

Neil Leifer: Lewiston, Maine, 1965. 

John Lennon

Bob Gruen: New York, 1974. John Lennon asked me to come to his penthouse apartment on the east side of New York to take pictures for the cover of his ‘Walls + Bridges’ album. After we took a series of portraits for the record cover we took some informal shots to use for publicity. I asked him if he still had the New York City t-shirt I had given him a year earlier and he went a put it on and we made this photo.

Napalm Attack In Vietnam

Nick Ut:  Trang Bang Village, 1972. Kim Phuc 9 year-old girl runs naked on a road after being severely burned from South Vietnamese napalm attacks. 

To find out more, please visit the Behind Photographs website.

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