If there's anything the last year has shown, it's that racial tension is still a reality in America.

But sometimes people use racist and offensive phrases without even realizing it.

Bigoted sentiments surround these nine terms, though in some cases their original meanings might have evolved.

1. "The itis"

More commonly known now as a "food coma," this phrase likely stems from a longer (and incredibly offensive) version — ni****itis. The condition alludes to the stereotype of laziness once associated with African-Americans.

Modern vernacular dropped the racial slur, leaving a faux-scientific diagnosis for the tired feeling after eating way too much food.

Try the technical term instead: postprandial somnolence. 

2. "Uppity"

Back in 2011, Rush Limbaugh said a NASCAR audience booed Michelle Obama because of "uppityism." Glenn Beck even defended him, saying the word was simply a synonym for "snobby."

In the late 1800s and early 1900s, however, black people were hanged for acting "uppity" or "insolent"— basically not knowing their place. A quick internet search shows the word often precedes "ni****." 

Originally, the term started within the black community, but racists adopted it pretty quickly.

3. "Gyp"

"Gyp" or "gip" most likely evolved as a shortened version of "gypsy"— an ethic group more correctly known as the Romani, now mostly in Europe. The Romani typically traveled a lot and made their money by selling goods. Business disputes naturally arose, and the masses started thinking of Romani as swindlers.

Today, "gyp" has become synonymous with cheating someone.

4. "Paddy wagons"

In modern slang, "paddy wagon" means a police car.

"Paddy" originated in the late 1700s as a shortened form of "Patrick," and then later a pejorative term for any Irishman. "Wagon" refers to a vehicle. "Paddy wagon" either stemmed from the large number of Irish police officers or the perception that rowdy, drunken Irishmen constantly ended up in the back of police cars.

5. "Hooligan"

This phrase started appearing in London newspapers around 1898. The Oxford Online Dictionary speculates it evolved from a fictional surname, "Houligan," included in popular pub songs, which other sources say might have evolved from Houlihan.

And Clarence Rook's book, "The Hooligan Nights," claims that Patrick Houlihan actually existed. He was a bouncer and a thief in Ireland.

The term has evolved into "football hooliganism," destructive behavior from European football (but really soccer) fans.

6. "Indian-giver"

Often a middle-school taunt for someone who gives a gift and promptly wants it back, "Indian-giver" originated from the phrase "Indian gift,"first used by Thomas Hutchinson in his 1765 book, "The History of the Province of Massachusetts Bay."

During interactions with Native Americans, he defined the term as a present "for which an equivalent return is expected." But he and his fellow colonists probably just misunderstood bartering. 

By the early 1900s, the phrase began to appear regularly as an idiom. 

7. "Sold down the river"

Today, if someone "sells you down the river,"  he or she betrays or cheats you. But the phrase has a much darker and more literal meaning.

During slavery in the US, masters in the North often sold their misbehaving slaves, sending them down the Mississippi River to plantations further south, where conditions were much harsher.

8. "Eenie meenie miney moe"

This phrase comes from a longer children's rhyme:

Eenie, meenie, miney, moe / Catch a tiger by the toe / If he hollers let him go / Eenie, meenie miney, moe

The rhyme has many versions, one of the oldest being where n***er replaces tiger. Rudyard Kipling mentions it as a "counting-out song" (basically a way for kids to eliminate candidates for being "It" in hide-and-seek) in "Land And Sea Tales For Scouts And Guides."

While the rhyme didn't necessarily originate with a racial slur, it became one of the most popular versions in the early 1900s, especially in the UK, according to the "Oxford Dictionary of Nursery Rhymes."

Bonus: "Rule of thumb"

A lot of people wrongly think the phrase "rule of thumb" references an old statute allowing men to beat their wives with a stick no wider than their thumbs. 

For example, The Telegraph reported just this year that judge Sir Francis Buller ruled in 1886 that "a man was entitled to beat his wife with a stick provided it was no thicker than his thumb." That ruling created the popular, and sexist, idiom, according to the Telegraph.

But way back in 1998, wordsmith William Safire told a different story in The New York Times. He cites "rule of thumb" as early as 1692 and then again, as an established proverb in 1721.

Buller did, however, make the ruling later in history. Someone should have knocked some sense into him — preferably with a stick much wider than a thumb.

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The siege of Tunisia's Bardo Museum is over. Terrorists in military uniform took over the museum in downtown Tunis, taking hostages and killing as many as 19 people. Two terrorists and a security officer were killed in the mayhem, but the situation has reportedly been stabilized. 

The museum holds one of the world's greatest collections of Roman and Byzantine mosaics, a treasure trove that evokes Tunisia's centrality to the history of imperial Rome. It was after the Roman defeat of Carthage in 149 BC that Rome really became an empire, attempting to project power and erase all memory of their north African enemies by building roads, palaces, cities, and even stadiums that survive in Tunisia to this day.

Tunis is a harmony of Arab and French influences, a multilingual city with broad, Parisian-style avenues leading to a walled ancient center. The country's cosmopolitan legacy might help explain why its post-Arab Spring transition to democracy has gone relatively smoothly, weathering a potentially hazardous constitutional re-write and multiple changes in power since longstanding dictator Zine Abidine ben Ali fled the country among protests in early 2011.

Like Egypt, Tunisia elected an Islamist-controlled parliament in its first post-Arab Spring vote; unlike Egypt, that government left power through a subsequent election rather than at gunpoint.

But this might also explain why Tunisia's been one of the world's biggest exporters of jihadists to Iraq and Syria. Over 3,000 Tunisians have traveled to the battlefield according to the Washington Post, the most of any other country. This is especially incredible considering Tunisia only has a population of 11 million.

Conservative resentment of the country's democratic turn – along with economic stagnation and frustration at the lack of a clear post-Arab Spring dividend — might explain the Jihadist exodus. Tunisia also has a nagging domestic jihadism problem, with occasional battles between security forces and extremist fighters in the country's Jebel Chambi region.

Today's attack at the Bardo is a sign that there are actors within the country who violently resent Tunisia's unique history, along with its special place within the post-Arab Spring Middle East. 

Here are some photos I took at the Bardo museum during a reporting trip in April of 2012.  Tunis is still one of the world's great cities. And despite today's atrocity, no visit would be complete without a stop at the Bardo.

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War has played a significant role in American history. 

Ever since the country's first war as a sovereign nation against the British Empire in 1812, the US's process for declaring and waging war has dramatically shifted. It used to be that fighting a war required the passage of a Congressional bill. Today, a simple presidential authorization of force is often all that's needed to send US troops into harm's way. 

The following infographic from New England College shows the US's history of military engagement, and shows how declaring war has changed throughout American history.

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From King Tut’s tomb and drunken Romans to Norse Viking voyages, wine has a rich and surprising history.

You might know your Merlot from your Malbec, but brushing up on this collection of little-known wine facts might just clinch you the top spot in your next pub quiz.

Ancient greeks invented the toast with wine

The term “toast” originated in ancient Rome when the Senate ordered that the emperor Augustus be honoured with a toast at every meal. The custom began with a piece of burnt toast, known as the “tostus”, being dropped into a glass of wine. This was done to mask the wine’s unpleasant flavours, the ancient equivalent of oaking. Everyone would then raise their glasses to the guest of honour, giving rise to today’s well-known custom.

However with treachery rife, and poisoning the preferred way to pay off outstanding debts, it became customary for Greek hosts to toast each guest before a meal, drinking from a common bowl to prove the wine had not been poisoned.

The world’s oldest bottle of wine is nearly 1,700 years old

The world’s oldest wine bottle is believed to date back to AD 325 and was found near the town of Speyer, Germany, in 1867. It is believed to be the oldest unopened bottle of wine in the world, the glass bottle carries 1.5 litres of liquid. The bottle was discovered during an excavation within a 4th-century AD Roman nobleman’s tomb which contained two sarcophagi, one holding the body of a man and one a woman.

It’s believed the man was a Roman legionnaire and that the wine was a provision for his celestial journey. Of the six glass bottles in the woman’s sarcophagus and the ten vessels in the man’s sarcophagus, only one still contained a liquid. While the liquid had lost all of its ethanol content, analysis is consistent with at least part of the liquid having been wine.

It is likely that the wine was produced in the same region and was diluted with a mixture of herbs. and preserved with a large amount of thick olive oil which had been added to the bottle to seal the wine off from air, along with a hot wax seal.

Fear of wine is an actual thing

While not a feeling most will have experienced, wine can apparently strike fear in the hearts of the unlucky few.

Oenophobia is the intense fear or hatred of wine and is officially defined as “the fear of wine; anxiety related to wine.”

Welcome to United States of “wine”

The  Norse Vikings called coastal North America and Newfoundland Vinland (“wine-land” or “pasture-land”) when they came ashore in AD 1000 because of the number of vines they found there. The coastline was first discovered by Leif Erikson in AD 1000, approximately five centuries prior to the voyages of Christopher Columbus.

In 1960, archaeological evidence of the only known Norse settlement in North America (outsideGreenland) was found at L’Anse aux Meadows on the northern tip of the island of Newfoundland. Before the discovery of archaeological evidence, Vinland was known only from Old Norse sagas and medieval historiography. The 1960 discovery conclusively proved the pre-Columbian Norse colonization of the Americas.

Thou shalt not sell fake wine

Well before the likes of Rudy Kurniawan started ripping off wine buyers the Code of Hummurabi helped keep wine fraudsters in line.

A well-preserved Babylonian law code of ancient Mesopotamia, dating back to about 1754 BC, the Code of Hammurabi is one of the oldest deciphered writings in the world. The Code consists of 282 laws, one of which states that anyone caught selling fraudulent wine should be drowned in a river.

One nearly complete example of the Code survives today written on a diorite stele in the shape of a huge index finger. It is currently on display in the Louvre, Paris.

Chateau Lafite anyone? No.

A “cork tease” is a recognised term defined by the Urban Dictionary as “someone who always promises to open up a great bottle of wine but never does.”

Used in context, “she kept telling me how great the wine was but wouldn’t open a bottle, she’s such a cork tease.”

Tutankhamun’s wine was very well labelled

The boy king Tutankhamun, who died in 1352BC, enjoyed a glass of red wine with several bottles found buried in his tomb by archeologists when it was opened in 1922. The wine jars were labelled with the wine’s name, year of harvest, source and even vine grower. 

So detailed were the labels that some of them could even have met modern wine label laws in several countries. The wine had unsurprisingly dried out by the time it was discovered, however a team of Spanish scientists were able to determine the jars had contained red wine by pinpointing remnants of a specific acid left in red wine.

Symposium is actually code for “drinking party”

You might think that a symposium is a meeting of academics or professionals to discuss their profession or debate current affairs, and you would be right, but it’s also an excuse to drink. The term symposium originated in ancient Greece and literally means, “drinking together”, reflecting the Greeks’ fondness for mixing wine and intellectual discussion.

Symposia were usually held in the the men’s quarters of the household with participants invited to recline on pillowed couches while they were served food, wine and entertained, all while discussing politics and philosophy. They were often held to celebrate the introduction of young men into aristocratic society. A symposium would be overseen by a “symposiarch”, an ancient version of a sommelier, who would decide how strong the wine for the evening would be based on how serious the discussion. It would typically be served mixed with water as drinking pure wine was considered a habit of uncivilized peoples.

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When they aren't digging up ancient graves or unearthing the body parts of early human ancestors, archaeologists are combing the Earth for clues about how the people who came before us lived, worked, played, and died.

This month, researchers in South America, Asia, Europe, and the Middle East have found evidence of everything from secret fortresses to the capitals of vanished civilizations, entire underground cities, and even ancient recipes.

Together, the findings provide a fascinating look into the thriving communities that preceded us.

The corner of a lost civilization found deep in the Honduran rain forest

Some 1,000 years ago in the middle of Honduras, a thriving populace once built giant statues, homes, and even a complex network of irrigation channels and reservoirs.

The flourishing enclave, uncovered using laser scanning technology by a team of researchers from the University of Houston, was likely part of a network of other dwellings throughout this part of the Honduran rain forest. Together, these sites would have formed an active community that bustled with hundred of people long before the arrival of European explorers.

So far, the researchers have already found evidence of the tips of more than 50 objects, including giant stones possibly used for construction purposes, the head of a large statue resembling a combination of a werewolf and a jaguar, stone seats for ceremonies, and containers that had been intricately etched with the figures of vultures and snakes. They estimate the community was active in sometime between A.D. 1000 and A.D. 1400.

A secret fortress of Genghis Khan found in southwest Mongolia

Genghis Khan's Mongolian Empire, the largest of its kind in history, stretched from the Sea of Japan to as far west as Arabia and from Siberia to as far south as India and Iran.

How did he come to control such a vast domain?

A team of archaeologists recently uncovered a clue that may help answer that question: A secret fortress that may have been used to help expand the empire during its westward march toward Europe.

The large fortress, located near what was once rich farmland and key parts of the silk trade route, would have played a key role in providing supplies and carrying information to the Mongolian army as they expanded west.

Inside the fortress, which measures about the size of three football fields and was likely built in 1212, researchers uncovered a vast array of Chinese pottery, wood fragments, and animal bones.

The oldest-ever-preserved beer from an 1840s shipwreck

Ever wonder what a bottle of 170-year-old beer would smell like?

Thanks to the recent discovery of a shipwreck off the coast of Finland, you don't have to keep guessing.

A team of researchers uncorked two bottles of the 19th-century-brew in early March, unleashing powerful odors of cabbage, burnt rubber, over-ripe cheese, and sulfur. When chemists analyzed the bottles' contents, they found the cause of the stench: bacteria that had likely been growing inside the bottles for decades, taking over any malty, beer-like smells they may once have had.

Bacteria aside, the beer probably tasted much like the beers we drink today, according to the researchers' chemical analysis of its other ingredients. Both brews were produced with hops but had a bit more of a rose-flavoring compound than we might be used to.

An ancient Celtic prince unearthed from his lavish tomb

Some 2,500 years ago, an ancient prince got a lavish burial in France.

His body was recently uncovered inside his chariot, along with pottery and a gold-tipped drinking vessel decorated with intricate images of Bacchus, the Greek god of wine and revelry.

The prince is not buried alone, however.

The burial site, located a few hours' drive south of Paris, houses many other ancient bodies. Nearby, researchers recently uncovered another grave dating to about 800 BC holding the body of an ancient warrior and his sword and a woman with bronze jewelry, Tia Ghose wrote in a recent post for LiveScience.

The tombs build on existing evidence that the Celtic and Mediterranean peoples exchanged goods. Mediterranean merchants were thought to have used Greek pottery frequently as gifts, contributing to the Celts' growing wealth inland.

A vast, underground city found in central Turkey

Deep in central Turkey in a region successively ruled by Alexander the Great, the Romans, the Byzantine Empire, and the Ottoman Empire, more than a hundred square miles of once-hidden passages snake beneath the ground.

The subterranean tunnels link thousands of underground homes and temples. Archaeologists who first discovered the hidden city in 2013 estimate the network once housed up to 200 villages and was most likely occupied until around 5,000 years ago, according to Hurriyet Daily News.

This March, a team of archaeologists and engineers began mapping the details of the underground terrain using machinery that sends radar pulses beneath the surface. Once it's mapped completely, the Anatolian government plans to open the area to the public.

Uncovered: A 250-year-old pretzel and other pastries

Archaeologists recently unearthed a pretzel that was likely served up sometime around 1765 in the southern German state of Bavaria. It could be the oldest surviving remnant of the doughy snack ever discovered in Europe.

Ancient traces of food are tough to find — once they're discarded, edible goods are quickly consumed by small animals and bacteria. But this pretzel was unique because it had been burned. The carbon in the burned remnant preserved it against the forces of time.

While digging for other remains in the city of Regensburg, archaeologists also found a handful of blacked rolls and other pretzel bits that suggests they were tossed from a bakery that was once located there, reports the Guardian. Carbon dating suggests the toasty treats were baked sometime between 1700 and 1800.

A hoard of ancient coins and jewelry in northern Israel

In the middle of their underground adventure in northern Israel, a group of amateur cavers accidentally discovered a stockpile of ancient coins and jewelry from the time of Alexander the Great.

Along with the stash of 2,300-year-old coins and silver rings, bracelets, and earrings, archaeologists who later excavated the site uncovered pottery dating back as far as 6,000 years.

Officials from the the Israel Antiquities Authority think people living in the area at the time may have stashed the valuables in the cave during the period of political turmoil that followed Alexander the Great's death in 323 BC.

This wouldn't be the first time someone stumbled across a mass treasure trove in the area. In February, amateur divers accidentally discovered a store of 2,000 gold coins off the coast of the ancient harbor city of Caesarea.

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When Yoshitaka Shindo was a boy, he did not hear much from his family about his grandfather Tadamichi Kuribayashi, commander of the Japanese troops who fought in the bloody battle of Iwo Jima.

The battle, in which nearly 7,000 US Marines and almost 22,000 Japanese defenders died, was etched in America's memory by an Associated Press photo of six soldiers raising the US flag on the small volcanic island's Mount Suribachi.

For many in Japan, however, it was long a tragic defeat best forgotten.

"Human beings don't want to talk about what is most painful," Shindo, a conservative ruling party lawmaker and former member of Prime Minister Shinzo Abe's cabinet, told Reuters in an interview.

"As a child, I was told that my grandfather worked diligently for the sake of the country and that he was a very gentle person. But as for details such as what happened when, neither my grandmother or mother really spoke about that."

Japanese Defense Minister Gen Nakatani and Health Minister Yasuhisa Shiozaki will attend a memorial service with US representatives on Saturday to mark the 70th anniversary of the epic 36-day battle.

More ordinary Japanese are now aware of the battle, in which just 1,083 Japanese defenders escaped death, in part because of Clint Eastwood's 2006 film "Letters from Iwo Jima," inspired by letters from Kuribayashi to his family on the eve of the battle.

But the years of silence have left a gap that makes it harder to pass on wartime experiences to younger Japanese.

"My grandfather didn't really like to speak about the war. At night, he would moan in his sleep. He would scream sometimes and I assumed it was because of the war," said Atsushi Hirano, 22, who has traveled to 11 battlefields including Iwo Jima, as a member of a group that collects the bones of fallen soldiers.

"But I always thought I couldn't ask about it and then he died six years ago. I wish I had asked him more," said Hirano, a college student studying to become a teacher.

'An honorable death'

The tiny tear-shaped island of Iwo Jima, 700 miles (1,000 kilometers) south of Tokyo, was the first scrap of Japan's native soil to be invaded in World War II. America wanted it as a base for fighters escorting B-29 bombers headed for the Japanese mainland.

Kuribayashi, who studied at Harvard and served as a military attache in the United States, had little hope of victory at a time when many Japanese leaders knew the war had been lost.

"The battle looms and except when I am tired and sleep, all I think of is the fierce fight, an honorable death, and what will happen to you and the children after that," the father of three wrote.

But aiming to inflict as much damage as possible on the US forces, Kurbayashi honeycombed the island with tunnels from which defenders could be dislodged only at great cost.

Shindo said his grandfather was believed to have been struck down by a bullet after he removed his officer's insignia and joined his troops in an attack on US forces.

Kuribayashi's bones have never been recovered — nor have the remains of more than half of the Japanese soldiers who died.

"They hid themselves on that fortress of an island and fought on alone to prolong the battle," Shindo said. "They think they are still fighting, so I want to bring them home as soon as possible."

(Editing by Robert Birsel)

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At the height of the gulag system, millions of Russians were imprisoned and put into forced labor. 

The gulag system housed citizens ranging from wayward peasants to political dissidents. Each year Stalin was in power, the gulag system grew larger.

Now, gulags are being turned into museums so Russians can learn the past atrocities commited under the Soviet Union.

Visitors to the Perm-36 museum in the Urals can stroll through a well-preserved prison camp of the Gulag system established by Soviet leader Josef Stalin.

But despite the authenticity of the site, the museum's new curators are downplaying the camp's role in the repressions of the Stalin era.

A stanza of the Soviet hymn from the late Stalin period is written on the wall facing museum visitors as they enter from the prison guard headquarters.

The prison guards' headquarters at the entrance to the camp

The “strict regime” zone of the prison camp

An unexploded German World War II bomb has been found in London, NBC News reports citing London police and fire officials. 

The unexploded bomb was found in the Bermondsey district of South London, approximately a mile away from the historic Tower Bridge. The bridge has been shut down as emergency services have cordoned off the area. 

The bomb was found by workmen at a construction site in Bermondsey. The ordnance is estimated at being five feet long and weighing a half ton. 

According to London's Southwark Council, an Army disposal team is working to deactivate and remove the bomb. To secure the area, residents in a 328 foot (100 meter) radius around the explosive have been evacuated from their homes while traffic has also been rerouted through London. 

The Independent notes that Bermondsey, formerly an industrial area, was one of the most heavily bombed neighborhoods of London during the Blitz, the Nazi air assault that lasted from September 1940 to May 1941. 

During the Blitz, the Germans bombed London a total of 71 times. In total, the Nazi Lutfwaffe dropped 100 tons of explosives on British cities during this stage of the war, killing 40,000 civilians. 

This is not the first time that a German bomb has been found in London after the end of the Blitz. The discovery of unexploded bombs does not "happen every day but they are not massively uncommon where there's building works going on," the London Fire Brigade told NBC. 

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When I was a kid, my parents had a collection of historic old, yellowed newspapers. For example, I distinctly remember an old Washington Post newspaper sitting on a bookshelf from July 21, 1969 with the headline “The Eagle Has Landed – Two Men Walk on the Moon.”

Or a fading, brownish-yellow one from August 8, 1974 with the big headline, “Nixon Resigns.”

These newspapers are fascinating artifacts documenting history, from remarkable moments to the relatively mundane. Unfortunately, they were also hard to read due to the yellowed, brown color and fading print. So why do old newspapers – and books – turn yellow? And is there any way to prevent this from happening?

It is generally thought that paper was invented around 100 BC in China. Originally made from wet hemp that was, then, beaten to a pulp, tree bark, bamboo, and other plant fibers were eventually used. Paper soon spread across Asia, first only being used for official and important documents, but as the process became more efficient and cheaper, it became far more common.

Paper first arrived in Europe likely around the 11th century. Historians believe the oldest known paper document from the “Christian West” is the Missal of Silos from Spain, which is essentially a book containing texts to be read during Mass. This paper was made out of a form of linen. While paper, books, and printing would evolve throughout the next eight hundred years, with the Gutenberg printing press coming in the mid-15th century, paper was normally made out of linen, rags, cotton, or other plant fibers. It wouldn’t be until the mid-19th century when paper was made out of wood fiber.

So what changed? In 1844, two individuals invented the wood paper-making process. On one end of the Atlantic Ocean was Canadian inventor Charles Fenerty. Growing up, his family owned a series of lumber mills in Nova Scotia. Knowing the durability, cheapness, and availability of wood, he realized it could be a good substitute for the much more expensive cotton used in paper. He experimented with wood pulp and on October 26, 1844, he sent his wood pulp paper to Halifax’s top newspaper, The Acadian Recorder, with a note touting the durability and cost-effective spruce wood paper. Within weeks, the Recorder used Fenerty’s wood pulp paper.

At the same time, German binder and weaver Friedrich Gottlob Keller was working on a wood-cutting machine when he discovered the same thing as Fenerty – that wood pulp could act as a cheaper paper than cotton. He produced a sample and, in 1845, received a German patent for it. In fact, some historians credit Keller for the invention more than Fenerty simply due to the fact that he received a patent and the Canadian did not.

Within thirty years, wood pulp paper was all the rage on both sides of the pond. While wood pulp paper was cheaper and just as durable as cotton or other linen papers, there were drawbacks. Most significantly, wood pulp paper is much more prone to being effected by oxygen and sunlight.

Wood is primarily made up of two polymer substances – cellulose and lignin. Cellulose is the most abundant organic material in nature. It is also technically colorless and reflects light extremely well rather than absorbs it (which makes it opaque); therefore humans see cellulose as white. However, cellulose is also somewhat susceptible to oxidation, although not nearly as much as lignin. Oxidation causes a loss of electron(s) and weakens the material. In the case of cellulose, this can result in some light being absorbed, making the material (in this case, wood pulp) appear duller and less white (some describe it as “warmer”), but this isn’t what causes the bulk of the yellowing in aged paper.

Lignin is the other prominent substance found in paper, newspaper in particular. Lignin is a compound found in wood that actually makes the wood stronger and harder. In fact, according to Dr. Hou-Min Chang of N.C. State University in Raleigh, “Without lignin, a tree could only grow to about 6 ft. tall.” Essentially, lignin functions as something of a “glue,” more firmly binding the cellulose fibers, helping make the tree much stiffer and able to stand taller than they otherwise would, as well able to withstand external pressures like wind.

Lignin is a dark color naturally (think brown-paper bags or brown cardboard boxes, where much of the lignin is left in for added strength, while also resulting in the bags/boxes being cheaper due to less processing needed in their creation). Lignin is also highly susceptible to oxidation. Exposure to oxygen (especially when combined with sunlight) alters the molecular structure of lignin, causing a change in how the compound absorbs and reflects light, resulting in the substance containing oxidized lignin turning a yellow-brown color in the human visual spectrum.

Since the paper used in newspapers tends to be made with a less intensive and more cost-efficient process (since a lot of the wood pulp paper is needed), there tends to be significantly more lignin in newspapers than in, say, paper made for books, where a bleaching process is used to remove much of the lignin. The net result is that, as newspapers get older and are exposed to more oxygen, they turn a yellowish-brown color relatively quickly.

As for books, since the paper used tends to be higher grade (among other things, meaning more lignin is removed along with a much more intensive bleaching process), the discolorization doesn’t happen as quickly. However, the chemicals used in the bleaching process to make white paper can result in the cellulose being more susceptible to oxidation than it would otherwise be, contributing slightly to the discolorization of the pages in the long run.

Today, to combat this, many important documents are now written on acid-free paper with a limited amount of lignin, to prevent it from deteriorating as quickly.

As for old historic documents – or my parent’s old newspapers – there may not be a way to reverse the damage already done, but one can prevent further damage. It is important to store the documents or newspaper in a cool, dry, dark place, just like how museums store historic documents in a temperature-controlled room with low-lighting. Additionally, do not store them in an attic or basement; those places can get humid and can have significant temperature swings. If one would like to display the newspaper or document out in the open, put it behind UV protected glass to deflect harmful rays. Most importantly, limit the handling of said document or newspaper – nothing destroys a valuable piece of paper like frequent handling.

If you liked this article, you might also enjoy:

• Why is Toilet Paper Always White?
• Toilet Paper wasn’t Commonly Used in the United States Until the Early 20th Century
• Why Paper Cuts Hurt So Much
• Why Blueprints are Blue
• The Invention of the Cardboard Box

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Reconstructions of human evolution are prone to simple, overly-tidy scenarios.

Our ancestors, for example, stood on two legs to look over tall grass, or began to speak because, well, they finally had something to say.

Like much of our understanding of early hominid behavior, the imagined diet of our ancestors has also been over-simplified.

Take the trendy Paleo Diet which draws inspiration from how people lived during the Paleolithic or Stone Age that ran from roughly 2.6 million to 10,000 years ago.

It encourages practitioners to give up the fruits of modern culinary progress – such as dairy, agricultural products and processed foods – and start living a pseudo-hunter-gatherer lifestyle, something like Lon Chaney Jr. in the film One Million BC. Adherents recommend a very specific "ancestral" menu, replete with certain percentages of energy from carbohydrates, proteins and fats, and suggested levels of physical activity.

These prescriptions are drawn mainly from observations of modern humans who live at least a partial hunter-gatherer existence.

But from a scientific standpoint, these kinds of simple characterizations of our ancestors' behavior generally don't add up. Recently, fellow anthropologist C. Owen Lovejoy and I took a close look at this crucial question in human behavioral evolution: the origins of hominid diet.

We focused on the earliest phase of hominid evolution from roughly 6 to 1.6 million years ago, both before and after the first use of modified stone tools.

This time frame includes, in order of appearance, the hominids Ardipithecus and Australopithecus, and the earliest members of our own genus, the comparatively brainy Homo. None of these were modern humans, which appeared much later, but rather our distant forerunners.

We examined the fossil, chemical and archaeological evidence, and also closely considered the foraging behavior of living animals. Why is this crucial?

Observing animals in nature for even an hour will provide a ready answer: almost all of what an organism does on a daily basis is simply related to staying alive; that includes activities such as feeding, avoiding predators and setting itself up to reproduce. That's the evolutionary way.

What did our ancestors actually eat? In some cases, researchers can enlist modern technology to examine the question. Researchers study the chemical makeup of fossil dental enamel to figure out relative amounts of foods the hominid ate derived from woody plants (or the animals that ate them) versus open country plants.

Other scientists look in ancient tooth tartar for bits of silica from plants that can be identified to type – for example, fruit from a particular plant family. Others examine the small butchering marks made on animal bones by stone tools. Researchers have found, for example, that hominids even 2.6 million years ago were eating the meat and bone marrow of antelopes; whether they were hunted or scavenged is hotly debated.

Such techniques are informative, but ultimately give only a hazy picture of diet. They provide good evidence that plants' underground storage organs (such as tubers), sedges, fruits, invertebrate and vertebrate animals, leaves and bark were all on the menu for at least some early hominids.

But they don't give us information about the relative importance of various foods. And since these foods are all eaten at least occasionally by living monkeys and apes, these techniques don't explain what sets hominids apart from other primates.

So how should we proceed? As my colleague Lovejoy says, to reconstruct hominid evolution, you need to take the rules that apply to beavers and use them to make a human. In other words, you must look at the "rules" for foraging. We aren't the first researchers to have dabbled in this. As long ago as 1953, anthropologists George Bartholomew and Joseph Birdsell attempted to characterize the ecology of early hominids by applying general biological principles.

Happily, ecologists have long been compiling these rules in an area of research dubbed optimal foraging theory (OFT). OFT uses simple mathematical models to predict how certain animals would forage in a given circumstance.

For instance, given a set of potential foods of estimated energetic value, abundance and handling time (how long it takes to acquire and consume), one classic OFT model calculates which resources should be eaten and which ones should be passed over.

One prediction — sort of a "golden rule" of foraging — is that when profitable foods (those high in energy and low in handling time) are abundant, an animal should specialize on them, but when they are scarce, an animal should broaden its diet.

Data from living organisms as disparate as insects and modern humans generally fall in line with such predictions.

In the Nepal Himalaya, for example, high-altitude gray langur monkeys eschew leathery mature evergreen leaves and certain types of roots and bark — all calorie-deficient and high in fibers and handling time — during most of the year. But in the barren winter, when better foodstuffs are rare or unavailable, they'll greedily devour them.

In another more controlled study, when differing quantities of almonds in or out of the shell are buried in view of chimpanzees, they later recover larger quantities (more energy), those physically closer (less pursuit time), and those without shells (less processing time) before smaller, more distant, or "with-shell" nuts.

This suggests that at least some animals can remember optimal foraging variables and utilize them even in cases where foods are distant and outside the range of immediate perception. Both of these studies support key predictions from OFT.

If one could estimate the variables important to foraging, one could potentially predict the diet of particular hominids that lived in the distant past. It's a daunting proposition, but this human evolution business was never meant to be easy.

The OFT approach forces researchers to learn how and why animals exploit particular resources, which leads to more thoughtful considerations of early hominid ecology. A smattering of scientists have utilized OFT with success, most notably in archaeological treatments of comparatively recent hominids, such as Neandertals and anatomically modern humans.

But a few brave souls have delved into more remote human dietary history. One team, for example, utilized OFT, modern analogue habitats, and evidence from the fossil record, to estimate the predicted optimal diet of Australopithecus boisei.

That's the famed "Nutcracker Man" that lived in East Africa close to 2 million years ago. The research suggests a wide range of potential foods, greatly varying movement patterns – based on characteristics such as habitat or use of digging sticks — and the seasonal importance of certain resources, such as roots and tubers, for meeting estimated caloric requirements.

Researchers Tom Hatley and John Kappelman noted in 1980 that hominids have bunodont– low, with rounded cusps – back teeth that show much in common with bears and pigs. If you've watched these animals forage, you know they'll eat just about anything: tubers, fruits, leafy materials and twigs, invertebrates, honey and vertebrate animals, whether scavenged or hunted.

The percentage contribution of each food type to the diet will depend (you guessed it) on the energetic value of specific foods in specific habitats, at specific times of year. Evidence from the entirety of human evolution suggests that our ancestors, and even we as modern humans, are just as omnivorous.

And the idea that our more ancient ancestors were great hunters is likely off the mark, as bipedality — at least before the advance of sophisticated cognition and technology — is a mighty poor way to chase game. Even more so than bears and pigs, our mobility is limited.

The anthropologist Bruce Latimer has pointed out that the fastest human being on the planet can't catch up to your average rabbit. Another reason to be opportunistic about food.

Simple characterizations of hominid ecology are divorced from the actual, and wonderful, complexity of our shared history. The recent addition of pastoral and agricultural products to many modern human diets — for which we have rapidly evolved physiological adaptations — is but one extension of an ancient imperative.

Hominids didn't spread first across Africa, and then the entire globe, by utilizing just one foraging strategy or sticking to a precise mix of carbohydrates, proteins and fats. We did it by being ever so flexible, both socially and ecologically, and always searching for the greener grass (metaphorically), or riper fruit (literally).

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The Bush family has been on something of a roll for the past five generations.

If we trace the lineage back to the mid-19th century, we see that the dynasty came to dominate in railroad, finance, and oil industries before seating two of its members in the Oval Office.

The Bushes are potentially looking to accomplish a presidential hat trick with Jeb Bush — son of George H.W. Bush and younger brother of George W. Bush — running for election in 2016.

While the later generations of the Bush family are the most well known, W. and Jeb have their grandfather, Prescott S. Bush, to thank for turning the family name into a dynasty.

We decided to look back at how his influence shaped the Bushes' legacy. This retrospective includes insights from Jacob Weisberg's exhaustive biography, "The Bush Tragedy," and vintage photos.

Born to an Ohio steel and railroad executive and his wife, Prescott S. Bush decided early on that he wanted nothing to do with his father's ventures in manufacturing. He would carve his own success story.

He burst onto the high-society scene as a tall, athletically gifted young man at Yale. He picked up varsity letters in baseball, hockey, and golf, sang with the Whiffenpoof Quartet, and belonged to the school's exclusive secret society, Skull and Bones.

After returning from World War I, Prescott found work selling hardware in St. Louis. There, he met an energetic 18-year-old named Dorothy Walker. Their union marked the beginning of the Walker-Bush lineage.

At the time, Dorothy's father, George Herbert "Bert" Walker, managed the famous Harrison brothers' enterprises at 1 Wall Street. He went on to become president of W.A. Harriman & Co.

Bert pulled some strings and found work for Prescott at the firm, though Prescott refused to admit he had any help getting there. Having the job handed to him betrayed his family's tradition of making a name for yourself.

Still, he used the chance to catapult himself to greater riches and power. He saved the Harrimans from significant losses after the financial crash in 1929 by slashing costs and facilitating a merger with a bank owned by fellow members of Yale's Skull and Bones.

Prescott went on to direct Union Banking Corp., an investment bank that facilitated the transfer of gold, oil, steel, and coal all over the globe during World War II. The bank's assets were later frozen under suspicion that the bank backed Nazi sympathizers.

Fortunately for Prescott, he didn't own his share in UBC; rather, he held it on behalf of a Dutch bank. A degree removed from Hitler's "secret nest egg," he was never found guilty of any crime.

During these years, living in Greenwich, Connecticut, Prescott and Dorothy had five children: four boys and one girl. The Bush kin grew up in a fiercely religious household that encouraged both loyalty and competitiveness. They wanted for nothing, vacationing at the Walker family's summer estate in Kennebunkport, Maine, and attending private schools. Still, Prescott's sense of modesty led him to squash any child's show of privilege.

The couple remained active in local affairs. Prescott moderated town meetings for more than 15 years and Dorothy volunteered at the Red Cross and at a welfare agency.

When Prescott reached his mid-50s, he finished paying off his children's tuition bills and felt financially secure enough to enter politics. In 1952, after a failed run at the US Senate two years prior, Prescott brought along a special guest on the campaign trail to rally supporters: his golf buddy, Dwight Eisenhower, fresh off a landslide presidential election.

Prescott won the Republican seat and served two terms as a Connecticut Senator, between 1952 and 1962. He left a legacy as a Northeastern moderate, supporting civil-rights legislation, larger immigration quotas, and higher taxes, and opposing increasing senators' salary. "In his vision, either an independent income or a monastic lifestyle was required for elected officials,"Jacob Weisberg writes in his book.

Prescott retired from the Senate because of ill health. He lived another 10 years, returning to the banking industry, and died of cancer in 1972.

His passion for politics, of course, trickled down to future generations of Bushes. Weisberg writes that, although George H.W. Bush never worked on any of his father's campaigns, he watched closely. He inherited his father's sense of duty.

"Prescott Bush established three essential myths that Bush men lived by," Weisberg writes. "The first is: I made it on my own. The second is: I'm not really rich. The third is: I'm running to serve my country."

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Most college career advisors wouldn't know what to do with Leonardo da Vinci. 

He didn't fit the mold of today's "high achievers"— going to school for law, medicine, or management, and then dedicating himself to that discipline.

Instead, he was a wide achiever, to use the words of "How to Find Fulfilling Work" author Roman Krznaric.

"In any one week,"Krznaric tells Business Insider, da Vinci "might be painting a portrait for an artistic patron or designing an engineering device for a power hungry duke from Milan — and then on the weekends doing anatomy experiments."

Da Vinci was, as they say, a Renaissance Man.

Nowadays, we call that approach being a portfolio worker, where you do several jobs at the same time. You could be freelancing articles to magazines and running digital strategy for a brand during the week, and then teaching yoga and cooking classes on the weekend.

While being spread that thin might sound unstable, Krznaric contends that it's not.

"In an era where nobody's jobs are secure anymore," he says, "spreading the risk across several portfolio jobs is probably quite a smart move to make."

Krznaric speaks from experience. After getting his Ph.D. from Essex University, he taught at Cambridge University before doing human rights work in Central America. He cofounded the School of Life in London, a place where people learn emotional intelligence and get coached on career transitions.

He's also written books, like "How Should We Live?: Great Ideas from the Past for Everyday Life" and "Empathy: Why It Matters, and How to Get It." In addition to giving talks, he's about the launch the Empathy Museum, a traveling exhibition designed "for stepping into the shoes of other people and looking at the world through their eyes."

One thing he's learned is that when you're managing three careers at once, you need to be adept at selling yourself — something da Vinci did quite well. 

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Hidden ten stories below Grand Central Terminal, a secret basement can be found. This basement was a prime New York City target during World War II, as it provided electricity for northeast trains dedicated to troop and equipment transport. The location remains confidential today, and continues to provide electricity to Metro-North trains. 

Produced by Justin Gmoser. Additional camera by Sam Rega. 

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The origin of Indo-European languages has long been a topic of debate among scholars and scientists.

In 2012, a team of evolutionary biologists at the University of Auckland led by Dr. Quentin Atkinson released a study that found all modern IE languages could be traced back to a single root: Anatolian — the language of Anatolia, now modern-day Turkey.

Produced by Alex Kuzoian

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Vladimir Putin is merely posing as a lieutenant colonel.

The Russian president also oversaw war crimes in Chechnya and helped frame a prosecutor-general to derail a probe into massive Kremlin corruption.

These are some of the claims made by Oleg Kalugin, a former high-ranking KGB officer and fierce critic of Putin in an interview with RFE/RL.

According to Kalugin, Putin was "just a major" in the KGB, which he resigned from in 1991. "He could have become a lieutenant colonel a year later but he didn't," he tells RFE/RL.

Kalugin, who lives in the United States and has been sentenced by Russia to 15 years in prison for treason, says Putin's 1998 appointment as director of the KGB's main successor agency, the Federal Security Service (FSB), actually violated guidelines stipulating that only a general can hold this post.

He also confirms speculation that the FSB was behind a sex-tape scandal that ended the career of Yury Skuratov, Russia's combative prosecutor-general in the late 1990s.

Kalugin says Skuratov was framed to prevent him from further investigating corrupt deals believed to have been conducted by former Russian President Boris Yeltsin, the man who brought Putin to power, and his close entourage — including his own daughters.

"It was a special FSB operation to discredit an official with the help of a video featuring a person who resembled the prosecutor-general," he says, referring to a controversial 1999 video showing a man purported to be Skuratov in bed with prostitutes.

In his interview, Kalugin also names two alleged former KGB collaborators: firebrand nationalist politician Vladimir Zhirinovsky and late Patriarch Aleksii, the former head of the powerful Russian Orthodox Church.

He says that he personally knew Aleksii and that the cleric had admitted to him his Soviet-era ties with the secret services, arguing it had been the only way to save the church at the time.

Markov Assassination

Kalugin also looks back on one of the 20th century's most brazen assassinations, the killing of Bulgarian writer and dissident Georgy Markov in London in the midst of the Cold War.

Kalugin says that Markov was killed by the Bulgarian secret services and that Yury Andropov, who then headed the Soviet KGB, gave the green light for the assassination.

Markov, who lived in political exile in the British capital, was poisoned with the tip of an umbrella as he waited for a bus on Waterloo Bridge in September 1978.

He died four days later, aged 49, leaving behind a wife and a 2-year-old daughter.

Kalugin claims Andropov initially planned to reject the Bulgarian security service's request for assistance in the killing. According to him, Andropov relented only because a refusal could have hurt Moscow's clout within the Bulgarian intelligence agency.

He says the KGB only aided its Bulgarian colleagues, with Andropov formally barring his subordinates from directly taking part in the assassination. "Through the KGB laboratory we transferred the poison that was then used in the umbrella," Kalugin says. "There was literally a milligram of poison, a small drop of ricin placed in a capsule at the tip of the umbrella. When the umbrella opened, it flew off at a distance of 3-5 meters, which is enough to prick someone."

Kalugin was detained in London in 1993 and questioned about the assassination. He was released without charge.

Markov's killers were never brought to justice.

Killed For Exposing Putin?

Incidentally, Kalugin is also connected to the case of Aleksandr Litvinenko, the former FSB officer who died in London in November 2006 after drinking tea laced with radioactive polonium-210.

Kalugin believes Litvinenko was killed by the FSB for disclosing what he describes as "uncomely aspects" of Putin's private life.

He says he had warned Litvinenko about the dangers of making such details public. "I called him when he was in London and told him he shouldn't be writing things about [Putin's] private life," he says. "Then he died, my warning had come too late."

The incident has not deterred Kalugin from openly criticizing Putin and his policies.

The two men have exchanged acerbic barbs, with Kalugin branding the Russian leader a "deadbeat" and a "war criminal" for sanctioning the atrocities perpetrated by Russian forces during the second Chechen War.

Asked whether he is not afraid of meeting the fate of Markov and Litvinenko, Kalugin claims to be protected by influential friends in Putin's close circle.

But there is one topic that he intends to keep under wraps for his own safety: Putin's shadowy private life. "When I'm asked about Putin," he says, "I answer, 'Ask his wife, he spent 30 years with her.'"

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Have you ever stopped to think WHY you're Saran Wrapping a toilet seat on April Fools' Day?

Do you think the first time a man pranked his neighbor everyone reveled in the delight of it so much they decided to make a holiday out of it? Is that where April Fools' Day came from?

Well, it's as good a guess as any because the origins of this high jinx-filled holiday aren't entirely solidified. There are, however, some strong theories of how it came about.

The most popular theory of the holiday actually has Catholic origins: In 1582, Pope Gregory XIII replaced the widely used Julian calendar with the now currently instated Gregorian calendar. This moved the start of the year from April 1st to January 1st.

Those who were late to catch on or refused to acknowledge the change and still celebrated the New Year in April were mocked and teased (humans are the best!). In France, a common prank was throwing paper fish at the springtime New Year's celebrators and calling them poisson d'avril, or April Fish, a term for a gullible person.

Other cultures and societies have springtime celebrations centering around foolishness and joviality. Hilaria was an ancient Roman celebration on the vernal equinox for Cybele, the mother of the gods. People would dress up in costumes and masks, imitating those in higher positions of power.

Sizdah Be-dar, which falls thirteen days after Nowruz, the Persian New Year, is an occasion where families gather outside for picnics and celebrate the return to ordinary life after the New Year. It's a day where laughter is used to overpower the bad omens and thoughts for the upcoming year.

In Hinduism, Holi is the spring festival of colors where crowds welcome the warming weather and longer days by throwing colored dyes on each other. Covered in layers of powdered dyes, people were indistinguishable by class, caste, or gender.

As with many other traditions/holidays, like Santa Claus, Thanksgiving, or Halloween, there doesn't seem to be one exact origin of April Fools' Day, which might be for the best. Why do we need one excuse to be silly?

Fool on, pranksters!

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You know you're in for a thrill when a related Google search for "Caminito del Rey" suggests "death toll."

Called the world's most dangerous trail, Caminito del Rey is a roughly five-mile walkway that clings to the walls of the El Chorro gorge in southern Spain. It closed in 2000 after a number of people fell to their deaths, and it reopened this month after a reported $5.8 million restoration project.

Reuters photographer Jon Nazca hiked the pathway before it opened to the public. Experience the journey for yourself by scrolling below.

The original path was built between 1901 and 1905 as an access road to two hydroelectric plants.

The locals began taking advantage of the trail on foot, bicycle, and horse. Women crossed to reach shops in the next village, and children used it to get to school. 

In 1921, King Alfonso XIII traversed the path on his way to the opening of a nearby dam. Locals named it "El Caminito del Rey," or the King's Little Pathway.

The boardwalk hangs 100 meters above the water, providing breathtaking views of Spain's natural beauty. The full route takes four to five hours to complete.

Time wore on the walkway, however, leaving it pockmarked and decrepit. In 1999 and 2000, several travelers died attempting to cross.

Local authorities shut it down by destroying the entry points. Anyone caught trespassing received a hefty fine of $6,500.

The ban made the hike only more appealing to daredevils, who would strap on GoPro cameras and upload videos of their jaunts to YouTube. 

The government took note of the walkway's popularity and decided to rebuild it, making the path safer and attracting more tourism dollars to the area.

A reported $5.8 million later, the new wooden and steel walkways hover just feet above the original route in some areas. The project's director and head architect, Luis Machuca, told The Guardian that preserving the thrill of the old path was crucial.

Visitors can purchase admission tickets to El Caminito del Rey online, though it is booked through June. An expected 600 people will cross every day.

"It's not only the view and the surroundings, but the emotion of walking the Caminito del Rey,"Machuca says.

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Astrophysicists probe the nature of our universe — a place too vast and grand for a single human mind to fully comprehend — and while that might make some feel small, Neil deGrasse Tyson has said time and again that the knowledge he's acquired over the years as an astrophysicist makes him feel not small, but big.

To deGrasse Tyson, knowledge is essential to leading a prosperous, meaningful life.

Even after publishing nearly a dozen books, narrating the hit series Cosmos: A Spacetime Odyssey, and directing the Hayden Planetarium in New York, deGrasse Tyson still tries to learn something new every day, he recently told 60 Minutes correspondent Charlie Rose.

Here are some of the few, but fundamentally important, life lessons that he says are his constant sources of inspiration.

"One of them is every day try to lessen the suffering of others by however amount," he told Rose.

The way deGrasse Tyson does this is through his role as a science educator.

As host of the widely-popular podcast StarTalk Radio and Cosmos star, deGrasse Tyson strives to make the wonders of the universe accessible to all.

If you understand your connection to the universe — that we are all made of the same stuff as the tens of billions of stars in our galaxy — then that knowledge gives you a sense of relevance and connection that you might never feel otherwise. And, according to deGrasse Tyson, feeling relevant in the world is what we, as a species, look for in life.

"Also I try to learn something today that I did not know yesterday," he told Rose. "Why not? There's so much to learn."

This is good advice for us all. In fact, experts say learning something new everyday will make you smarter overall and protect your brain from some of the negative aspects of normal aging.

Learning new things isn't just important for the brain, however. Several studies have found that people who regularly experience awe in their lives generally feel less stressed, more humble, and more satisfied too. So it's in our best interest to seek out those special quirks that awe and inspire us as we learn more about life and the universe.

Last, but not least, deGrasse Tyson tries to live his life by following the advice of a 19th Century American politician and educator, Horace Mann: "Be ashamed to die until you've scored some victory for humanity."

DeGrasse Tyson reiterated Mann's words with his own.

"You want the world to be a slightly better place for you having lived in it," he told Rose. "If you have the power and the influence to make it a slightly better place and you don't, what kind of life is that?"

When deGrasse Tyson saw Mann's quote for the first time, he decided that he would strive to one day deserve those words as his epitaph.

We think he's doing a pretty good job so far.

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DEARBORN, Mich. (AP) -- Jeff Buczkiewicz stood before the chair Abraham Lincoln was sitting in when he was assassinated 150 years ago. He peered silently into the glass-enclosed case at the rocking chair, then snapped pictures for posterity.

"You just get drawn into these things," said Buczkiewicz, 47, who came from suburban Chicago with his family to the Henry Ford Museum in Dearborn, Michigan. "It is a tragic part of our history and our country. I think it's important to take it all in."

Taking in objects from the final hours of two important American lives is a major draw to the museum. In addition to the worn, red chair Lincoln was sitting in when he was shot in Ford's Theatre in Washington, D.C., in 1865, the Henry Ford also owns the limousine President John F. Kennedy was riding in when he was fatally shot in Dallas nearly a century later. Museum officials say the chair and car are among the most visited artifacts in the museum, along with the bus Rosa Parks rode in when she refused to give up her seat to a white rider and helped spark the civil rights movement.

Next week, visitors will get an even closer look at the Lincoln chair: It will be removed from its enclosure and displayed in an open plaza area as part of the museum's observance of the assassination's sesquicentennial on April 15 - a day of free admission. Two days earlier, it will be onstage when renowned historian and Lincoln expert Doris Kearns Goodwin delivers a sold-out lecture at The Henry Ford.

Goodwin, author of "Team of Rivals: The Political Genius of Abraham Lincoln," told The Associated Press that the chair will offer an extra "dimension" to her words and the experience of those in the room.

"There's an intimacy to it that catapults you back in time," she said. "And hopefully, along with that, you're not just thinking of the death but the life that made it worthwhile."

Lincoln's chair has been part of the museum started by pioneering automaker Henry Ford - no relation to the theater-owning Ford family - since its founding 85 years ago. The government removed it from the theater and held it as evidence, and it ended up at the Smithsonian Institution. The wife of a theater co-owner petitioned to reclaim it, then sold it at auction to an agent working for Henry Ford.

Henry Ford also bought the Logan County Courthouse where Lincoln practiced law in Illinois in the 1840s and moved it to the outdoor area next to his museum known as Greenfield Village. For decades, the theater chair was housed in that courthouse.

Around 1980, the chair was placed inside the museum, where it's now part of the "With Liberty and Justice for All" exhibit.

"Lincoln was one of Henry Ford's heroes - when he decided he wanted to have this village, he wanted to collect Lincoln stuff as an educational tool," said curator Donna Braden. "The courthouse is pretty much the first thing Henry Ford acquired related to Lincoln and the chair came soon after."

Many visitors wonder whether dark spots on the back of the chair are Lincoln's blood. Not so, say museum workers: The stains are oil from other people's heads who sat in the chair before that fateful night when Lincoln was shot by a pro-Confederacy actor, John Wilkes Booth.

Steve Harris, a historic presenter at the museum, tells passers-by that Lincoln's head would have been positioned much higher than the stain because he was 6 feet 4 inches tall (1.93 meters).

Milestone anniversaries seem to add to the impact of objects like the chair and limo. About 8,000 people visited the limo on Nov. 22, 2013, a free-admission day marking the 50th anniversary of JFK's assassination, so the chair is likely to draw plenty of visitors on the Lincoln anniversary.

"It really is about the power of the artifact," said Patricia Mooradian, president of The Henry Ford, as the entire history attraction is known. "It's less about the artifact itself than the symbolic nature of the artifact that represents a great paradigm change in the history of our country."

Buskiewicz has also visited Dealey Plaza in Dallas where Kennedy was assassinated. "You just have to try to take it in when you're in those areas," he said, but he wonders "why we gravitate" toward places and things associated with these types of events.

Goodwin, whose book helped inspire Steven Spielberg's movie, "Lincoln," says that standing before iconic yet everyday objects provides a deep experience that transcends the moment that made them famous.

"In some ways, it's more familiar when it's a chair, a bus or a limo," she said. "There's something about the tangibility of these things."

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A group of as-yet unidentified artists affixed a bust of NSA leaker Edward Snowden atop a column along the edges of the Prison Ship Martyr's Monument in Brooklyn's Fort Green neighborhood on April 6th before city parks officials ordered it removed.

According to Animal New York, whose Bucky Turco documented the bust's installation, a few of the artists involved in the project are based on the west coast; one of them estimated that the fabrication, transport, and installation of the statue required an estimated $30,000 of materials, travel, and labor.

There was nothing haphazard about this cross-country, high-budget artistic conspiracy, including its decision to install the statue atop the remains of soldiers who died fighting for the Continental Army during the Revolutionary War.

"In researching the location, we discovered remains of POWs from the Revolutionary War were interned as part of the memorial," the artist said through Turco, whom Business Insider contacted with questions about the artists' awareness of the site's significance as a mass grave.

"We questioned if they sacrificed their lives for the same freedoms and ideals people like Snowden continue to fight for. We hope placing this piece here brings an added relevance and new attention to their losses. This honors not only their fight and cause, but the current struggle to keep their vision alive."

The Prison Ship Martyrs Monument is a 149-foot pillar built in 1908 to commemorate the thousands of revolutionary soldiers who died while detained aboard British ships moored in and around New York Harbor.

They lived in incredible squalor: As the New York Parks Department's website explains, "Over 11,500 men and women died of overcrowding, contaminated water, starvation, and disease aboard the ships, and their bodies were hastily buried along the shore." 

By 1808, the prisoners' remains had been consolidated in a site near the Brooklyn Navy Yard, and they were moved to the current location of the Prison Ship Martyrs Monument in 1847.

The Monument is more than just a memorial to soldiers who died as part of the struggle to create the world's first republican democracy. It's also where thousands of them are actually buried.

The artists' selection of the Ship Martyr's monument was highly deliberate, and they clearly sought to demonstrate a well-studied respect for the monument and what they believe it to signify.

They wanted to draw attention to what they see as Snowden's continuity with earlier generations of authority-questioning American patriots as opposed to, says, presenting the now Moscow-based leaker — or his political and cultural canonization, among a certain crowd — as a break with American democratic tradition.

"It's not just about the bust, it's about the context, because it's a continuation of story that was started hundreds of years ago," one of the still-anonymous artists, speaking through a voice harmonizer, told Animal New York in a video posted on the site. The artist also noted the importance of  "honoring the aesthetics that are already in place." 

The group was careful not to damage the memorial itself: "We're installing it in a way that it could be removed without doing permanent damage to the structure," one artist said.

Care aside, one could reasonably ask whether the final resting place of thousands of unidentified American patriots is an appropriate venue for politically motivated guerilla art — even leaving aside the still-ongoing debate over Snowden's motives and decision-making in the course of affecting the single biggest leak of classified intelligence information in American history.

The artists are apparently prepared for the accusation that their work trivializes or desecrates sacred ground. They could have picked a more sensitive site than a mass tomb to carry out their project, but they deemed this particular mass tomb to be especially suitable for political and artistic appropriation.

"Our research revealed the memorial 's long history includes many cycles of neglect (though it’s currently in wonderful care)," the artists wrote in the statement relayed to Business Insider through Turco. "This makes it even more clear that through the years their sacrifices have gone under-appreciated. Our hope is this new attention on the memorial in some small way helps break the cycle."

Maybe their sacrifice has gone underappreciated, but the artists' attempted tribute may not be missing something: An NBC News poll from mid-2014 found that 2/3rds of respondents had a negative impression of Snowden, while a plurality did not support the leaker's actions.

One would think the approval rating is much higher for the revolutionary soldiers entombed near the Prison Ship Martyrs Monument.

SEE ALSO: John Oliver exposed a very big lie surrounding Edward Snowden

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