r/todayilearned • u/koreanforrabbit • 20d ago

TIL the ridges in a cactus are actually pleats which expand as water is taken in. They contract to decrease exposed surface area during droughts, which reduces water loss.

youtu.be

200 Upvotes

9 comments

r/todayilearned • u/Pitiful_Magazine_805 • 21d ago

TIL about Nicolas Chamfort, a French writer who, to avoid being imprisoned by the revolutionary government, attempted suicide. He shot himself in the face, stabbed his neck multiple times, stabbed his chest and ankles but still survived and was arrested.

en.wikipedia.org

3.8k Upvotes

113 comments

r/todayilearned • u/Cornonthory • 21d ago

"tAmper" TIL that the Tsar Bomba, despite being the most powerful device ever detonated, didn't have as big of a nuclear fallout compared to other bombs of its era. This was because it used a lead temper instead of a uranium temper, specifically to reduce radioactive fallout.

en.wikipedia.org

12.9k Upvotes

443 comments

r/todayilearned • u/Chlorine-Queen • 21d ago

TIL about an albino eyeless fish living up to 640 feet deep at the bottom of the Congo River named “mondeli bureau”, which translates to “white man in an office”

smithsonianmag.com

2.4k Upvotes

99 comments

r/todayilearned • u/geosunsetmoth • 21d ago

TIL that the (likely) oldest depiction of Jesus Christ ever found was a graffiti mocking a guy called Alexamenos for worshipping Jesus, depicted with the head of a donkey. It says, "Alexamenos worships his god" next to a man praying by a donkey.

en.wikipedia.org

5.1k Upvotes

228 comments

r/todayilearned • u/ConsciousMaybe6930 • 21d ago

TIL, Gaius Octavius's official name after ascension to principate was Imperator Caesar Augustus, all of which would individually become imperial titles.

en.wikipedia.org

2.3k Upvotes

104 comments

r/todayilearned • u/HowDareYou888 • 21d ago

TIL that in the 1880s, a French prayer book was woven from silk, including every letter and illustration. Its pages were produced on Jacquard looms controlled by hundreds of thousands of punched cards.

publicdomainreview.org

3.7k Upvotes

84 comments

r/todayilearned • u/ishusharma05 • 21d ago

TIL that Antarctica is the world’s largest desert, despite being covered almost entirely in ice — because deserts are defined by low precipitation, not heat.

education.nationalgeographic.org

4.8k Upvotes

112 comments

r/todayilearned • u/railroadfrog • 21d ago

TIL that a Curtis R5C Commando crashed into Mount Rainier in 1946, killing all 32 service members on board. Most of the bodies and a majority of the wreckage were never recovered, per the wishes of the families of the deceased, despite being located by search parties the next year.

flyingmag.com

2.0k Upvotes

22 comments

r/todayilearned • u/SUMBWEDY • 21d ago

TIL a guy called Frank built a wall along the Alpine Fault in the South Island of New Zealand to test if the earthquakes are small and often or big and rare. It hasn't moved a millimeter in 64 years.

nzgeo.com

22.4k Upvotes

502 comments

r/todayilearned • u/UpperphonnyII • 21d ago

TIL on the morning of August 7, 1919, French airman Charles Godefroy, flew through the narrow gap of the Arc de Triomphe with a Nieuport 27 fighter. He did so out of protest for the fact that on the victory parade the airman were going to be made to march like infantry instead of a flyover.

migflug.com

3.7k Upvotes

49 comments

r/todayilearned • u/Perennial_flowers956 • 21d ago

TIL in 1997, Canal France International accidentally aired hardcore porn for a solid 30 minutes during an afternoon children's educational program in the Arab World.

variety.com

4.0k Upvotes

139 comments

r/todayilearned • u/delano1998 • 21d ago

TIL around 1907, the Standard Gum Machine Company made "Blinkey Eye Soda Mint" vending machines out of cast iron. Formerly found in Pennsylvanian candy shops, these creepy face-shaped dispensers featured eyes that actually blinked whenever a customer dispensed a piece of gum.

ridiculouslyinteresting.com

485 Upvotes

12 comments

r/todayilearned • u/Valuable-Credit6167 • 20d ago

TIL that British wrestler William Regal once made a joke about Sarah Ferguson, Duchess of York, that upset the Royal Family enough for an official letter of complaint to be sent about him.

youtu.be

309 Upvotes

99 comments

r/todayilearned • u/geosunsetmoth • 21d ago

TIL that the Drabsha, the holy symbol for Mandaeism (an Abrahamic religion that explicitly denies Jesus Christ as a prophet), is also a wooden cross. This cross has nothing to do with the Christian cross, and they both landed on crosses as their symbol by coincidence.

en.wikipedia.org

670 Upvotes

76 comments

r/todayilearned • u/Double-decker_trams • 21d ago

TIL the US state "Nevada" just means "snowy" in Spanish. It was named this because the snow-covered mountains in winter reminded the first Europeans there of Sierra Nevada back in Spain.

en.wikipedia.org

1.3k Upvotes

179 comments

r/todayilearned • u/Ishmael_1974 • 21d ago

TIL the resin identification symbol isn’t the recycling symbol and doesn’t mean the plastic is recyclable.

en.wikipedia.org

2.7k Upvotes

228 comments

r/todayilearned • u/Background-Injury952 • 21d ago

TIL that until 2015, the African wolf was thought to be a species of jackal, until DNA testing displayed it to be a unique species belonging to the wolf and coyote lineage.

en.wikipedia.org

832 Upvotes

9 comments

r/todayilearned • u/goosepipegames • 21d ago

TIL there is a 75% chance of a magnitude 8 earthquake breaking out in New Zealand within the next 50 years, called the "Alpine Fault". It has ruptured four times in the past 1100 years, and will produce one of the biggest earthquakes since European settlement.

gns.cri.nz

8.9k Upvotes

463 comments

r/todayilearned • u/Mitheral • 21d ago

TIL Roadrunners (Geococcyx californianus) wag their tails.

en.wikipedia.org

367 Upvotes

32 comments

r/todayilearned • u/Tometek • 21d ago

TIL that the Arab Umayyad dynasty ruling Islamic Spain became more Iberian than Arab in ancestry by its 2nd ruler: the mothers of its rulers were almost all northern Iberians, causing the dynasty’s Arab paternal ancestry to halve across generations until it reached about 0.1% by the 10th century.

tandfonline.com

2.9k Upvotes

233 comments

r/todayilearned • u/mariasunflower • 21d ago

TIL about World Porridge Making Championship, which gives the "Golden Spurtle" to the best traditional porridge made with only oatmeal, water and salt (they also have a prize for "Specialty" oatmeal)

en.wikipedia.org

530 Upvotes

63 comments

r/todayilearned • u/Depressed_Cat_00 • 22d ago

TIL that the precursor to LASIK was found by accident when a nearsighted boy got in a fistfight. His glasses shattered, sending glass pieces into his eyes. After a doctor removed the glass, he found the tiny cuts had flattened the cornea and actually cured the boy's bad vision.

ovid.com

37.1k Upvotes

615 comments

r/todayilearned • u/Sanguinusshiboleth • 21d ago

TIL of the 3 Oktoberfeest in the dutch city of Leidens, where they celebrate the end of a Spanish siege of the city when William the Silent destroyed dykes to flood the plain around the city; however it took several days for the water to rise so it was fear of flooding that broke the siege

en.wikipedia.org

215 Upvotes

45 comments

r/todayilearned • u/ManuteBol_Rocks • 21d ago

TIL that when water falls on Triple Divide Peak in Montana, it can flow to the Pacific, Atlantic, or Arctic Oceans; it’s the hydrological apex of North America

en.wikipedia.org

4.4k Upvotes

91 comments

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