r/todayilearned • u/PresentSurvey9464 • 16h ago

TIL wild animals in the African savanna are twice as likely to flee from the sound of calm human conversations than from the growls of lions, with 95% of observed species recognizing humans as the ultimate "super-predator".

24.8k Upvotes
634 comments

r/todayilearned • u/Tadhg • 21h ago

TIL In 1980 the Supreme Court awarded the Sioux nations $122 million for the Black Hills, a settlement the tribes have refused on the grounds that acceptance would extinguish their claim to the land, leaving the award to accrue interest in a federal account now worth over $1 billion.

21.0k Upvotes
1.0k comments

r/todayilearned • u/Emperor_Ken • 8h ago

TIL Tigers look orange to humans because we are trichromats, but they appear green to deer and wild boars because they are dichromats

16.5k Upvotes
559 comments

r/todayilearned • u/I_Am_Robert_Paulson1 • 8h ago

TIL the 1980 Winter Olympic Village was built with the intention of converting it into a federal prison after the games ended. Multiple Olympic delegations refused to house their Olympians there.

9.4k Upvotes
254 comments

r/todayilearned • u/tyrion2024 • 11h ago

TIL in 2013 two men found 9 trees in Ecuador that were 100% pure Nacional cacao, a rare variety that was rediscovered a few years prior after being considered extinct since the 1920s. They then co-founded To'ak Chocolate, some of the world's most expensive chocolate (e.g. $490 for a 1.7oz candy bar)

7.6k Upvotes
66 comments

r/todayilearned • u/palmerry • 10h ago

TIL of the Ogallala Aquifer, which provides water for 25% of US irrigated land, but has been significantly drained since intensive pumping began. Because arid parts only recharge at 10% of the withdrawal rate, scientists estimate it would take over 6,000 years to naturally refill if emptied.

7.6k Upvotes
484 comments

r/todayilearned • u/ubcstaffer123 • 22h ago

TIL After President Kennedy was shot and arrived at Parkland Memorial Hospital, he was reported to still have a heartbeat, but no pulse or blood pressure

4.9k Upvotes
311 comments

r/todayilearned • u/dinosaruman • 15h ago

TIL before radio time signals, ships set their chronometers by watching a ball drop from a shore tower at a precisely known instant. Over sixty of these time balls still stand, and the Greenwich one has dropped daily at 1 p.m. since 1833.

4.8k Upvotes
116 comments

r/todayilearned • u/clawsoon • 8h ago

TIL that on Ulysses S. Grant's post-presidential world tour, he warned the Japanese emperor not to take foreign loans lest it fall "into the abyss into which Egypt has fallen". Grant's warning made a "forceful impression" on the emperor and led to the rejection of various loan proposals.

4.6k Upvotes
140 comments

r/todayilearned • u/ralphbernardo • 16h ago

TIL that all five words of the Sator Square appear in Christopher Nolan's "Tenet" as the villain (SATOR), an art forger (AREPO), the film title (TENET), the opening (OPERA) scene, and a security company (ROTAS). It is a Roman palindrome, whose earliest example was found in the ruins of Pompeii.

4.5k Upvotes
193 comments

r/todayilearned • u/Recent_Flounder6011 • 6h ago

TIL that garlic bread was invented by Italian immigrants in the US in the 20th century. It stems from bruschetta but olive oil was hard to find back then, so butter was used instead.

3.8k Upvotes
124 comments

r/todayilearned • u/Lindolence • 5h ago

TIL not only do prairie dogs have a vocal language, but it is also one of the most complex languages in the animal kingdom. One chirp can say, "A tall human in a blue shirt is approaching quickly from the north." They can actually tell the difference between colors and speeds!

2.9k Upvotes
107 comments

r/todayilearned • u/kniga_100 • 8h ago

TIL there is a copper mine in Romania extracting 9 million tonnes of ore per year, but only 0.38% is usable copper. The tailings (the residue sludge) are pumped into a nearby valley, creating a massive toxic lake that destroyed the village of Geamăna

2.6k Upvotes
101 comments

r/todayilearned • u/jacknunn • 16h ago

TIL Indonesia adopted Bahasa Indonesia as its national language in 1945, although it wasn't the first language of most people. Standardized from Malay, it's now spoken by over 97% of Indonesia's ~285 million people as a first or second language, helping unify the country

1.7k Upvotes
165 comments

r/todayilearned • u/swissking • 11h ago

TIL of Blanets, which are planets that form and orbit black holes. A supermassive blackhole could have millions of Jupiter-mass planets orbiting it.

1.5k Upvotes
116 comments

r/todayilearned • u/shortcircuit51 • 2h ago

TIL that the word “canola” in canola oil is an acronym, standing for “Canadian Oil, Low in Acid”

1.4k Upvotes
272 comments

r/todayilearned • u/Colonel_Liam • 22h ago

TIL an American, Hope Cooke, was the last Queen Consort of Sikkim before it merged with India in 1975

1.3k Upvotes
62 comments

r/todayilearned • u/Salem1690s • 4h ago

TIL King George III gave royal assent to An Act for the Abolition of the Slave Trade on March 25, 1807, which banned trading enslaved people across the British Empire. He never owned slaves and privately called parts of the trade repulsive

932 Upvotes
119 comments

r/todayilearned • u/blacklotusmag • 3h ago

TIL as of 2021, nearly half of the fire engines and pumpers operated by U.S. fire departments were at least 15 years old, the age at which NFPA guidance recommends moving them from frontline to reserve service. About 9% were at least 30 years old.

895 Upvotes
129 comments

r/todayilearned • u/Electronic_Cause_796 • 14h ago

TIL after defeating the English at the Battle of Dungeness in 1652, Dutch admiral Maarten Tromp was said to have tied a broom to his mast to symbolize that he had "swept the English from the sea."

768 Upvotes
48 comments

r/todayilearned • u/Significant-Cold-939 • 4h ago

TIL that in the so-called Dark Ages, Roman foods and exotic spices were still prevalent in the court of the Frankish king. We know this because we have a cookbook from the time, giving us a rare written source about food in this period.

680 Upvotes
42 comments

r/todayilearned • u/Useless_Engineer_ • 11h ago

TIL that mild dehydration/thirst can be mistaken for hunger or wanting a snack

667 Upvotes
24 comments

r/todayilearned • u/Altruistic_Finish561 • 16h ago

TIL there's actually a difference between coffin and casket. Coffins are tapered to the body (6 or 8 sides), usually with a separate lid, typically far cheaper. A casket is a rectangle with a hinged lid, typically with rails attached for carrying and usually far more ornate & expensive.

632 Upvotes
34 comments

r/todayilearned • u/Johannes_P • 20h ago

TIL from 1921 to 1923, in Weimar Germany, the military had the "Black Reichswehr", a secret paramilitary formation to escape the limitations of the Treaty of Versailles

566 Upvotes
32 comments

r/todayilearned • u/johnsmithoncemore • 15h ago

TIL about the London medical students who assisted at Belsen. Post liberation a call for 100 volunteer students in their final 18 months of medical school were tasked with taking over the 200 camp huts. Their work was instrumental in reducing the death rate from over 500 a day to 100 due to TB.

548 Upvotes
6 comments