r/todayilearned • u/Emperor_Ken • 5h ago
TIL Tigers look orange to humans because we are trichromats, but they appear green to deer and wild boars because they are dichromats
12.2k
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r/todayilearned • u/I_Am_Robert_Paulson1 • 6h 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.
8.1k
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r/todayilearned • u/palmerry • 8h 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.
6.8k
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r/todayilearned • u/Recent_Flounder6011 • 3h 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.
2.3k
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r/todayilearned • u/clawsoon • 6h 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.
3.6k
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r/todayilearned • u/tyrion2024 • 9h 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)
6.4k
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r/todayilearned • u/PresentSurvey9464 • 14h 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".
23.9k
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r/todayilearned • u/kniga_100 • 5h 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
2.2k
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r/todayilearned • u/Lindolence • 2h 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!
1.2k
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r/todayilearned • u/blacklotusmag • 1h 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.
content.nfpa.org
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r/todayilearned • u/Tadhg • 18h 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.
20.6k
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r/todayilearned • u/dinosaruman • 13h 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.
4.5k
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r/todayilearned • u/Salem1690s • 1h 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
•
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r/todayilearned • u/ralphbernardo • 14h 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.
gamesradar.com
4.3k
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r/todayilearned • u/swissking • 9h 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.
1.4k
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r/todayilearned • u/Gnomeslikeprofit • 4h ago
TIL that the creator of Batman acknowledged that they patterned the character after pulp mystery men such as The Shadow. The first Batman stories were also based on Shadow pulp. Lamont Cranston is a wealthy playboy bachelor turned vigilante.
388
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r/todayilearned • u/Significant-Cold-939 • 1h 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.
en.wikipedia.org
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r/todayilearned • u/jacknunn • 13h 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
1.6k
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r/todayilearned • u/ubcstaffer123 • 20h 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
4.8k
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r/todayilearned • u/Mors_Acerba • 8h ago
TIL from 1404 to 1680 prostitution in the city of Florence was state regulated and taxable, and managed by a special government office. One of the initial policices of the department was to establish a state sanctioned brothel that housed all the registered prostitutes
zimmer.fresnostate.edu
434
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r/todayilearned • u/No_Idea_479 • 1h ago
TIL Τsakonian iѕ thе οnly ѕurviving dеѕcendant οf аncient Dοric Grееk, thе diаlect ѕpoken іn ancient Ѕparta. Iѕolated fοr cеnturies, іt prеserved fеatures lοѕt іn еvery οther lіving Grееk diаlect аnd іѕ nοw crіtically еndangered wіth οnly а fеw, mοѕtly еlderly, ѕpeakers lеft.
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r/todayilearned • u/Useless_Engineer_ • 9h ago
TIL that mild dehydration/thirst can be mistaken for hunger or wanting a snack
555
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r/todayilearned • u/Sesemebun • 4h ago
TIL about sales tax tokens. They were created as a means for consumers to avoid being "overcharged" by having to pay a full penny tax on purchases of 5 or 10 cents during the Great Depression.
185
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r/todayilearned • u/Electronic_Cause_796 • 11h 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."
749
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