iStock
iStock

25 Species That Have Made Amazing Comebacks

iStock
iStock

Conservationists can’t afford to become complacent. When it comes to rescuing endangered species, progress is an ongoing effort. Still, we can take comfort in the knowledge that many life forms which were once on the brink of extinction or endangerment have made tremendous comebacks with our help. Just look at what happened to these 25 plants and animals.

1. THE BALD EAGLE

A profile of a bald eagle on a black background
iStock

For much of the twentieth century, this American icon was in jeopardy. Habitat loss, overhunting, and the widespread use of DDT—an insecticide which weakens avian eggshells—once took a major toll on bald eagles. By 1963, the species population in the lower 48 states had fallen from an estimated 100,000 individuals to just 417 wild pairs. To turn things around, the U.S. government passed a series of laws, including a 1973 ban on DDT that was implemented by the Environmental Protection Agency (EPA). These efforts paid off; today, approximately 10,000 wild breeding pairs are soaring around in the lower 48.

2. THE ARABIAN ORYX

arabian oryx
iStock

The Arabian oryx is a kind of desert antelope indigenous to the Middle East. Reckless hunting devastated the species, which became essentially extinct in the wild during the early 1970s. However, a few individual animals were still alive and well in captivity. So, in the 1980s, American zoos joined forces with conservationists in Jordan to launch a massive breeding program. Thanks to their efforts, the oryx was successfully reintroduced to the Arabian Peninsula, where over 1000 wild specimens now roam (with a captive population of about 7000).

3. THE GRAY WOLF

gray wolves
iStock

Even well-known conservationists like Theodore Roosevelt used to vilify America’s wolves. Decades of bounty programs intended to cut their numbers down to size worked all too well; by 1965, only 300 gray wolves remained in the lower 48 states, and those survivors were all confined to remote portions of Michigan and Minnesota. Later, the Endangered Species Act enabled the canids to bounce back in a big way. Nowadays, 5500 of them roam the contiguous states.

4. THE BROWN PELICAN

Brown pelican perched on a dock piling
iStock

Louisiana’s state bird, the brown pelican, is another avian species that was brought to its knees by DDT. In 1938, a census reported that there were 500 pairs of them living within the Pelican State’s borders. But after farmers embraced DDT in the 1950s and 1960s, these once-common birds grew scarce. Things got so bad that, when a 1963 census was conducted, not a single brown pelican had been sighted anywhere in Louisiana. Fortunately, now that the era of DDT is over, the pelican’s back with a vengeance on the Gulf Coast and no longer considered endangered.

5. ROBBINS’ CINQUEFOIL

Robbins' Cinquefoil
Wikimedia Commons // Public Domain

Noted for its yellow flowers, Robbins’ cinquefoil—or Potentilla robbinsiana—is an attractive, perennial plant that’s only found in New Hampshire’s White Mountains and Franconia Ridge. Collectors once harvested the cinquefoil in excessive numbers and careless backpackers trampled many more to death. In response, the U.S. Fish and Wildlife Service re-routed hiking trails away from the flower’s wild habitats. This, along with a breeding program, rescued the Robbins' cinquefoil from the brink of extinction.

6. THE AMERICAN ALLIGATOR

Alligator emerging from swamp
iStock

With its population sitting at an all-time low, the American alligator was recognized as an endangered species in 1967. Working together, the Fish and Wildlife Service and governments of the southern states the reptiles inhabit took a hard line against gator hunting while also keeping tabs on free-ranging communities. In 1987, it was announced that the species had made a full recovery.

7. THE NORTHERN ELEPHANT SEAL

Elephant seal winking
iStock

Due to its oil-rich blubber, the northern elephant seal became a prime target for commercial hunters. By 1892, some people were beginning to assume that it had gone extinct. However, in 1910, it was discovered that a small group—consisting of less than 100 specimens—remained at large on Guadalupe Island. In 1922, Mexico turned the landmass into a government-protected biological preserve. From a place of security, that handful of pinnipeds bred like mad. Today, every single one of the 160,000 living northern elephant seals on planet Earth are that once-small group’s descendants.

8. THE HUMPBACK WHALE

humpback whale
iStock

Did you know that the world’s humpback whale population is divided into 14 geographically-defined segments? Well, it is—and in 2016, the National Ocean and Atmospheric Administration (NOAA) informed the press that nine of those clusters are doing so well that they no longer require protection under the U.S. Endangered Species Act. The cetaceans’ comeback is a huge win for the International Whaling Commission, which responded to dwindling humpback numbers by putting a ban on the hunting of this species in 1982. (That measure remains in effect.)

9. THE RED WOLF

red wolf
iStock

After the red wolf was declared “endangered” in 1973, the U.S. Fish and Wildlife Service rounded up every wild member of the species they could find and put them all into captivity. By then, the canid’s formerly wide geographical range had been reduced to a small portion of coastal Texas and Louisiana. FWS officials only managed to locate 17 wolves—14 of whom helped kick off a successful breeding program. Meanwhile, the red wolf was declared extinct in the wild in 1980. But thanks to those original 14 animals, we now have a captive red wolf population of 200. The FWS has also used their stock to release additional wolves into national wildlife refuges.

10. THE WHITE RHINO

rhino with birds
iStock

Make no mistake: The long-term survival of Earth’s largest living rhino is still very uncertain because poachers continue to slaughter them en masse. Nevertheless, there is some good news. Like black-footed ferrets and northern elephant seals, white rhinos were once presumed to be extinct. But in 1895, just under 100 of them were unexpectedly found in South Africa. Thanks to environmental regulations and breeding efforts, more than 20,000 are now at large.

11. THE WILD TURKEY

iStock

It’s hard to imagine that these poultry birds were ever in any real trouble, and yet they looked destined for extinction in the early 20th century. With no hunting regulations to protect them, and frontiersmen decimating their natural habitat, wild turkeys disappeared from several states. By the 1930s, there were reportedly less than 30,000 left in the American wilderness. Now, over 6 million are strutting around. So what changed? A combination of bag limits set by various agencies and an increase in available shrublands.

12. THE BLACK-FOOTED FERRET

black-footed ferret
USFWS Mountain-Prairie, Flickr // CC BY 2.0

North America’s only indigenous ferret is a prairie dog-eater that was written off as “extinct” in 1979. But the story of this animal took a surprising twist two years later, when a Wyoming pooch gave a freshly-dead one to its owner. Amazed by the canine’s find, naturalists soon located a wild colony. Some of these ferrets were then inducted into a breeding program, which helped bring the species’ total population up to over 1000.

13. THE CALIFORNIA CONDOR

California condor
iStock

Since 1987, the total number of California condors has gone up from 27 birds to about 450, with roughly 270 of those being wild animals. With its 10-foot wingspan, this is the largest flying land bird in North America.

14. THE GOLDEN LION TAMARIN

two tamarins
iStock

A flashy, orange primate from Brazil’s Atlantic Forest, the golden lion tamarin has been struggling to cope with habitat destruction. The species hit rock-bottom in the early 1970s, when fewer than 200 remained in the wild. A helping hand came from the combined efforts of Brazil’s government, the World Wildlife Federation, public charities, and 150 zoos around the world. There’s now a healthy population of captive tamarins tended to by zookeepers all over the globe. Meanwhile, breeding, relocation, and reintroduction campaigns have increased the number of wild specimens to around 1700—although urban sprawl could threaten the species with another setback. But at least the animal doesn’t have a PR problem: Golden lion tamarins are so well-liked that the image of one appears on a Brazilian banknote.

15. THE ISLAND NIGHT LIZARD

Native to three of California’s Channel Islands, this omnivorous, four-inch reptile was granted federal protection under the Endangered Species Act in 1977. The designation couldn’t have come at a better time, as introduced goats and pigs were decimating the night lizard’s wild habitat in those days. But now that wild plants have been reestablished under FWS guidance, more than 21 million of the reptiles are believed to be living on the islands.

16. THE OKARITO KIWI

Small, flightless, island birds usually don’t fare well when invasive predators arrive from overseas. (Just ask the dodo.) New Zealanders take great pride in the five kiwi species found exclusively in their country, including the Okarito kiwi, which is also known as the Okarito brown or rowi kiwi. These animals have historically suffered at the hands of introduced dogs and stoats. But recently, there’s been some cause for celebration. Although there were only about 150 Okarito kiwis left in the mid-1990s, conservation initiatives have triggered a minor population boom, with about 400 to 500 adult birds now wandering about—and that population is growing by two percent a year. Taking note of this trend, the International Union for Conservation of Nature (IUCN) has just declared that the Okarito kiwi is no longer endangered.

17. THE BROWN BEAR

brown bear
iStock

Let’s clear something up: The famous grizzly bear technically isn’t its own species. Instead, it is a North American subspecies of the brown bear (Ursus arctos), which also lives in Eurasia. Still, grizzlies are worth mentioning here because of just how far they’ve come within the confines of Yellowstone National Park. In 1975, there were only 136 of them living inside the park. Today, approximately 700 of them call the place “home,” a turn of events that led to the delisting of Yellowstone’s grizzlies as a threatened species under the Endangered Species Act earlier this year.

18. THE THERMAL WATER LILY

With pads that can be as tiny as one centimeter across, the thermal water lily is the world’s smallest water lily. Originally discovered in 1985, it was only known to grow in Mashyuza, Rwanda, where it grew in the damp mud surrounding the area’s hot spring. Or at least it did. The thermal water lily seems to have disappeared from its native range. Fortunately, before the species went extinct in the wild, some seeds and seedlings were sent to London’s Royal Botanic Gardens. There, horticulturalists figured out a way to make the lilies flower in captivity, and managed to saved the species.

19. THE PEREGRINE FALCON

Peregrine falcon flying
iStock

When a peregrine falcon dives toward its airborne prey, the bird-eating raptor has been known to hit speeds of up to 242 miles per hour. The species endured a plummet of a different sort when DDT dropped America’s population. In the first few decades of the 20th century, there were around 3900 breeding pairs in the United States. By 1975, the number of known pairs had been whittled down to 324. Things got better after the insecticide was banned, and according to the FWS, somewhere between 2000 and 3000 peregrine falcon couples currently patrol the skies in the United States, Canada, and Mexico.

20. PRZEWALSKI’S HORSE

Photo of a a wild Przewalski's horse on a snow covered field in the Chernobyl exclusions zone
GENYA SAVILOV/AFP/Getty Images

There are a few different subspecies of wild horse, all of which are endangered. One variant is the Przewalski’s horse (Equus ferus perzewalskii) from Mongolia. It completely vanished from that nation during the 1950s, but by then assorted zoos around the world had started breeding them. From 1992 to 2004, some 90 captive-born horses were released into Mongolia. They thrived and around 300 are living out there today.

21. THE NORTH AMERICAN BEAVER

North American beaver
iStock

No one knows how many of these buck-toothed rodents were living on the continent before European fur traders showed up. But after two centuries of over-trapping, incentivized by the lucrative pelt trade, the number of North American beavers had shrunk to an abysmal 100,000 in 1900. Their fortunes reversed when restocking programs were implemented in the U.S. and Canada. Nowadays, somewhere between 10 and 15 million beavers live in those countries. Given their landscaping talents, many property owners have come to see the furballs as pests.

22. THE CAFÉ MARRON

Rodrigues Island in the Indian Ocean once gave biologists a chance to raise the (near) dead. This landmass is the home of a small tree with star-shaped flowers called the café marron. It was thought that the plant had long since died out when a single specimen was found by a schoolboy named Hedley Manan in 1980. As the only surviving member of its species known to mankind, that lone plant assumed paramount importance. Cuttings from the isolated café marron were used to grow new trees at England’s Royal Botanical Gardens. Right now, there are more than 50 of these plants—and all of them can have their ancestry traced straight back to that one holdout tree.

23. THE WEST INDIAN MANATEE

A docile, slow-moving marine mammal with a taste for sea grasses, the Floridian subspecies of the West Indian manatee is a creature that does not react well to razor-sharp propellers. Collisions with boats are a significant threat, and the danger won’t go away altogether. Still, the passage of tighter boating regulations has helped the Sunshine State rejuvenate its manatee population, which has more than tripled since 1991.

24. THE BURMESE STAR TORTOISE

Burmese star tortoise
iStock

The pet trade did a number on these guys. Beginning in the 1990s, wildlife traffickers harvested Burmese star tortoises until they effectively became “ecologically extinct” in their native Myanmar. Luckily, conservationists had the foresight to set up breeding colonies with specimens who’d been confiscated from smugglers. The program started out with fewer than 200 tortoises in 2004; today, it has more than 14,000 of them. “Our ultimate objective is to have about 100,000 star tortoises in the wild,” Steve Platt, a herpetologist who’s been taking part in the initiative, said in a Wildlife Conservation Society video.

25. THE GIANT PANDA

panda in tree
iStock

Here we have it: the poster child for endangered animals everywhere … except that the giant panda is no longer endangered. Last year, the IUCN changed its status from “endangered” to “vulnerable.” There’s still a chance that we could lose the majestic bamboo-eater once and for all someday, but the last few years have offered a bit of hope. Between 2004 and 2014, the number of wild pandas saw a 17 percent increase. The welcome development was made possible by enacting a poaching ban and seeing an explosion of new panda reserves. It’s nice to know that, with the right environmental policies, we can make the future brighter for some of our fellow creatures.

nextArticle.image_alt|e
Zach Hyman, HBO
10 Bizarre Sesame Street Fan Theories
Zach Hyman, HBO
Zach Hyman, HBO

Sesame Street has been on the air for almost 50 years, but there’s still so much we don’t know about this beloved children’s show. What kind of bird is Big Bird? What’s the deal with Mr. Noodle? And how do you actually get to Sesame Street? Fans have filled in these gaps with frequently amusing—and sometimes bizarre—theories about how the cheerful neighborhood ticks. Read them at your own risk, because they’ll probably ruin the Count for you.

1. THE THEME SONG CONTAINS SECRET INSTRUCTIONS.

According to a Reddit theory, the Sesame Street theme song isn’t just catchy—it’s code. The lyrics spell out how to get to Sesame Street quite literally, giving listeners clues on how to access this fantasy land. It must be a sunny day (as the repeated line goes), you must bring a broom (“sweeping the clouds away”), and you have to give Oscar the Grouch the password (“everything’s a-ok”) to gain entrance. Make sure to memorize all the steps before you attempt.

2. SESAME STREET IS A REHAB CENTER FOR MONSTERS.

Sesame Street is populated with the stuff of nightmares. There’s a gigantic bird, a mean green guy who hides in the trash, and an actual vampire. These things should be scary, and some fans contend that they used to be. But then the creatures moved to Sesame Street, a rehabilitation area for formerly frightening monsters. In this community, monsters can’t roam outside the perimeters (“neighborhood”) as they recover. They must learn to educate children instead of eating them—and find a more harmless snack to fuel their hunger. Hence Cookie Monster’s fixation with baked goods.

3. BIG BIRD IS AN EXTINCT MOA.

Big Bird is a rare breed. He’s eight feet tall and while he can’t really fly, he can rollerskate. So what kind of bird is he? Big Bird’s species has been a matter of contention since Sesame Street began: Big Bird insists he’s a lark, while Oscar thinks he’s more of a homing pigeon. But there’s convincing evidence that Big Bird is an extinct moa. The moa were 10 species of flightless birds who lived in New Zealand. They had long necks and stout torsos, and reached up to 12 feet in height. Scientists claim they died off hundreds of years ago, but could one be living on Sesame Street? It makes sense, especially considering his best friend looks a lot like a woolly mammoth.

4. OSCAR’S TRASH CAN IS A TARDIS.

Oscar’s home doesn’t seem very big. But as The Adventures of Elmo in Grouchland revealed, his trash can holds much more than moldy banana peels. The Grouch has chandeliers and even an interdimensional portal down there! There’s only one logical explanation for this outrageously spacious trash can: It’s a Doctor Who-style TARDIS.

5. IT’S ALL A RIFF ON PLATO.

Dust off your copy of The Republic, because this is about to get philosophical. Plato has a famous allegory about a cave, one that explains enlightenment through actual sunlight. He describes a prisoner who steps out of the cave and into the sun, realizing his entire understanding of the world is wrong. When he returns to the cave to educate his fellow prisoners, they don’t believe him, because the information is too overwhelming and contradictory to what they know. The lesson is that education is a gradual learning process, one where pupils must move through the cave themselves, putting pieces together along the way. And what better guide is there than a merry kids’ show?

According to one Reddit theory, Sesame Street builds on Plato’s teachings by presenting a utopia where all kinds of creatures live together in harmony. There’s no racism or suffocating gender roles, just another sunny (see what they did there?) day in the neighborhood. Sesame Street shows the audience what an enlightened society looks like through simple songs and silly jokes, spoon-feeding Plato’s “cave dwellers” knowledge at an early age.

6. MR. NOODLE IS IN HELL.

Can a grown man really enjoy taking orders from a squeaky red puppet? And why does Mr. Noodle live outside a window in Elmo’s house anyway? According to this hilariously bleak theory, no, Mr. Noodle does not like dancing for Elmo, but he has to, because he’s in hell. Think about it: He’s seemingly trapped in a surreal place where he can’t talk, but he has to do whatever a fuzzy monster named Elmo says. Definitely sounds like hell.

7. ELMO IS ANIMAL’S SON.

Okay, so remember when Animal chases a shrieking woman out of the college auditorium in The Muppets Take Manhattan? (If you don't, see above.) One fan thinks Animal had a fling with this lady, which produced Elmo. While the two might have similar coloring, this theory completely ignores Elmo’s dad Louie, who appears in many Sesame Street episodes. But maybe Animal is a distant cousin.

8. COOKIE MONSTER HAS AN EATING DISORDER.

Cookie Monster loves to cram chocolate chip treats into his mouth. But as eagle-eyed viewers have observed, he doesn’t really eat the cookies so much as chew them into messy crumbs that fly in every direction. This could indicate Cookie Monster has a chewing and spitting eating disorder, meaning he doesn’t actually consume food—he just chews and spits it out. There’s a more detailed (and dark) diagnosis of Cookie Monster’s symptoms here.

9. THE COUNT EATS CHILDREN.

Can a vampire really get his kicks from counting to five? One of the craziest Sesame Street fan theories posits that the Count lures kids to their death with his number games. That’s why the cast of children on Sesame Street changes so frequently—the Count eats them all after teaching them to add. The adult cast, meanwhile, stays pretty much the same, implying the grown-ups are either under a vampiric spell or looking the other way as the Count does his thing.

10. THE COUNT IS ALSO A PIMP.

Alright, this is just a Dave Chappelle joke. But the Count does have a cape.

nextArticle.image_alt|e
iStock
17 Things to Know About René Descartes
iStock
iStock

The French polymath René Descartes (1596-1650) lived after the Renaissance, but he personified that age's interest in mathematics, philosophy, art, and the nature of humanity. He made numerous discoveries and argued for ideas that people continue to grapple with. (His dualist distinction between mind and the brain, for example, continues to be debated by psychologists.) Get to know him better!

1. NOBODY CALLED HIM RENÉ.

Descartes went by a nickname and often introduced himself as “Poitevin” and signed letters as “du Perron.” Sometimes, he went so far to call himself the “Lord of Perron.” That’s because he had inherited a farm from his mother’s family in Poitou, in western France.

2. SCHOOL MADE HIM FEEL DUMBER.

From the age of 11 to 18, Descartes attended one of the best schools in Europe, the Jesuit College of Henry IV in La Flèche, France. In his later work Discourse on the Method, Descartes wrote that, upon leaving school, “I found myself involved in so many doubts and errors, that I was convinced I had advanced no farther in all my attempts at learning, than the discovery at every turn of my own ignorance."

3. HIS DAD WANTED HIM TO BE A LAWYER.

Descartes’s family was chock-full of lawyers, and the budding intellectual was expected to join them. He studied law at the University of Poitiers and even came home with a law degree in 1616. But he never entered the practice. In 1618, a 22-year-old Descartes enlisted as a mercenary in the Dutch States Army instead. There, he would study military engineering and become fascinated with math and physics.

4. HE CHANGED CAREER PATHS THANKS TO A SERIES OF DREAMS.

In 1618, the Emperor of the Holy Roman Empire, Ferdinand II, attempted to impose Catholicism on anybody living within his domain. The result of this policy would be the Thirty Years' War. It would also prompt Descartes, a Catholic, to switch allegiances to a Bavarian army fighting for the Catholic side. But on his travels, he stopped in the town of Ulm. There, on the night of November 10, he had three dreams that convinced him to change his life’s path. “Descartes took from them the message that he should set out to reform all knowledge,” philosopher Gary Hatfield writes in the Stanford Encyclopedia of Philosophy.

5. HE COULD BE EASILY DISTRACTED BY BRIGHT AND SHINY OBJECTS.

In 1628, Descartes moved to the Netherlands and spent nine months doggedly working on a theory of metaphysics. Then he got distracted. In 1629, a number of false suns—called parhelia, or “sun dogs”—were seen near Rome. Descartes put his beloved metaphysics treatise on the back burner and devoted his time to explaining the phenomenon. It was a lucky distraction: It led to his work The World, or Treatise on Light.

6. HE LAID THE GROUNDWORK FOR ANALYTIC GEOMETRY ...

In 1637, Descartes published his groundbreaking Discourse on the Method, where he took the revolutionary step of describing lines through mathematical equations. According to Hatfield, “[Descartes] considered his algebraic techniques to provide a powerful alternative to actual compass-and-ruler constructions when the latter became too intricate.” You might have encountered his system in high school algebra: They’re called Cartesian coordinates.

7. ... AND THE REST OF WESTERN PHILOSOPHY.

Everybody knows Descartes for his phrase Cogito, ergo sum (which originally appeared in French as "Je pense, donc je suis"), or "I think, therefore I am." The concept appeared in many of his texts. To understand what it means, some context is helpful: At the time, many philosophers claimed that truth was acquired through sense impressions. Descartes disagreed. He argued that our senses are unreliable. An ill person can hallucinate. An amputee can feel phantom limb pain. People are regularly deceived by their own eyes, dreams, and imaginations. Descartes, however, realized that his argument opened a door for "radical doubt": That is, what was stopping people from doubting the existence of, well, everything? The cogito argument is his remedy: Even if you doubt the existence of everything, you cannot doubt the existence of your own mind—because doubting indicates thinking, and thinking indicates existing. Descartes argued that self-evident truths like this—and not the senses—must be the foundation of philosophical investigations.

8. HE'S THE REASON YOUR MATH TEACHER MAKES YOU CHECK YOUR WORK.

Descartes was obsessed with certainty. In his book Rules for the Direction of the Mind, “he sought to generalize the methods of mathematics so as to provide a route to clear knowledge of everything that human beings can know,” Hatfield writes. His advice included this classic chestnut: To solve a big problem, break it up into small, easy-to-understand parts—and check each step often.

9. HE LIKED TO HIDE.

Descartes had a motto, which he took from Ovid: “Who lives well hidden, lives well.” When he moved to the Netherlands, he regularly changed apartments and deliberately kept his address a secret. Some say it's because he simply desired privacy for his philosophical work, or that he was avoiding his disapproving family. In his book titled Descartes, philosopher A. C. Grayling makes another suggestion: "Descartes was a spy."

10. HE WASN'T AFRAID OF CRITICS. IN FACT, HE RE-PUBLISHED THEM.

When Descartes was revising his Meditations on First Philosophy [PDF], he planned to send the manuscript to “the 20 or 30 most learned theologians” for criticism—a sort of proto-peer review. He collected seven objections and published them in the work. (Descartes, of course, had the last word: He responded to each criticism.)

11. HE COULD THROW SHADE WITH THE BEST OF THEM.

In the 1640s, Descartes’s pupil and friend Henricus Regius published a broadsheet that distorted Descartes’s theory of the mind. (Which, put briefly, posits that the material body and immaterial mind are separate and distinct.) The two men had a falling out, and Descartes wrote a rebuttal with a barbed title that refused to even acknowledge Regius’s manifesto by name: It was simply called “Comments on a Certain Broadsheet.”

12. HE NEVER BELIEVED MONKEYS COULD TALK.

There’s a “fun fact” parading around that suggests Descartes believed monkeys and apes could talk. He believed no such thing. According to the Stanford Encyclopedia of Philosophy, Descartes denied that animals were even conscious, let alone capable of speech. The factoid comes from a misreading of a letter Descartes had written in 1646, in which he attributed the belief to “savages.”

13. HE TOTALLY HAD THE HOTS FOR CROSS-EYED WOMEN.

In a letter to Queen Christina of Sweden, Descartes explained that he had a cross-eyed playmate as a child. “I loved a girl of my own age ... who was slightly cross-eyed; by which means, the impression made in my brain when I looked at her wandering eyes was joined so much to that which also occurred when the passion of love moved me, that for a long time afterward, in seeing cross-eyed women, I felt more inclined to love them than others.”

14. WHEN HE MET BLAISE PASCAL, THEY GOT INTO AN ARGUMENT ... ABOUT VACUUMS.

In 1647, a 51-year-old Descartes visited the 24-year-old prodigy and physicist Blaise Pascal. Their meeting quickly devolved into a heated argument over the concept of a vacuum—that is, the idea that air pressure could ever be reduced to zero. (Descartes said it was impossible; Pascal disagreed.) Later, Descartes wrote a letter that, depending on your translation, said that Pascal had “too much vacuum in his head.”

15. HIS WORK WAS BANNED BY THE CATHOLIC CHURCH.

Back in the late 1630s, the theologian Gisbert Voetius had convinced the academic senate of the University of Utrecht to condemn the philosopher’s work. (Descartes was Catholic, but his suggestion that the universe began as a “chaotic soup of particles in motion,” in Hatfield's words, was contrary to orthodox theology.) In the 1660s, his works were placed on the church’s Index of Prohibited Books.

16. HE REGULARLY SLEPT UNTIL NOON (AND TRYING TO BREAK THE HABIT MIGHT HAVE KILLED HIM).

Descartes was not a morning person. He often snoozed 12 hours a night, from midnight until lunchtime. In fact, he worked in bed. (Sleep, he wisely wrote, was a time of “nourishment for the brain.”) But according to the Journal of Historical Neuroscience, he may have had a sleep disorder that helped end his life. A year before his death, Descartes had moved to Stockholm to take a job tutoring Queen Christina, a devoted early-riser who forced Descartes to change his sleep schedule. Some believe the resulting sleep deprivation weakened his immune system and eventually killed him.

17. HIS SKELETON HAS TRAVELED FAR AND WIDE.

Descartes died in Stockholm in 1650 and was buried outside the city. Sixteen years later, his corpse was exhumed and taken to Paris. During the French Revolution, his bones were moved to an Egyptian sarcophagus at the Museum of French Monuments. Decades later, when plans were made to rebury Descartes in an abbey, officials discovered that most of his bones—including his skull—were missing. Shortly after, a Swedish scientist discovered a newspaper advertisement attempting to sell the polymath’s noggin [PDF]. Today, his head is in a collection at the Musée de l’Homme in Paris.

SECTIONS

arrow
LIVE SMARTER
More from mental floss studios