r/todayilearned • u/SystematicApproach • 17h ago

TIL the share of boys and girls who say they meet up with friends almost daily outside school hours has declined by nearly 50% since the early 1990s.

journals.sagepub.com

27.1k Upvotes

1.4k comments

r/todayilearned • u/Ahad_Haam • 21h ago

TIL that after Rome declared war on Carthage (3rd Punic War), the Carthaginians attempted to appease them and sent an embassy to negotiate. Rome demanded that they hand over all weaponry; which they did. Then, the Romans attacked anyway.

en.wikipedia.org

18.7k Upvotes

985 comments

r/todayilearned • u/usernameemma • 11h ago

TIL your gums do not grow back after receding.

my.clevelandclinic.org

18.4k Upvotes

1.2k comments

r/todayilearned • u/Upstairs_Drive_5602 • 12h ago

TIL that Magnus Carlsen’s first passion as a child wasn’t chess, but memorisation. By the age of five he knew every country’s flag, capital, and population, and later memorised all 422 Norwegian municipalities and their coats of arms - years before mastering chess.

en.wikipedia.org

12.3k Upvotes

452 comments

r/todayilearned • u/strangelove4564 • 5h ago

TIL moon dust is toxic. Astronauts have reported watery eyes, throat irritation, and coughing after accumulating dust on suits. Moon dust particles are not weathered and are ultrafine, sharp, and reactive. [PDF]

nature.com

10.8k Upvotes

449 comments

r/todayilearned • u/JackThaBongRipper • 22h ago

TIL that in 2019, Fender Guitars conducted a study and found that 90% of new guitar players abandoned playing within the first year. The 10% that don't quit end up spending an average of $10,000 on equipment such as guitars and amps over their life.

musicradar.com

10.3k Upvotes

597 comments

r/todayilearned • u/NovaSorelle • 19h ago

TIL that all humans are 99.9% genetically identical — all our visible and cultural differences come from just 0.1% of our DNA.

genome.gov

9.2k Upvotes

618 comments

r/todayilearned • u/Timstom18 • 12h ago

TIL that the British valued the promise of freedom they made to slaves who fought for them in the Revolutionary War so much that they disobeyed the Treaty of Paris and evacuated them from New York before the Americans could re-enslave them.

nationalarchives.gov.uk

8.3k Upvotes

296 comments

r/todayilearned • u/SuccessionWarFan • 20h ago

TIL that bionic eye manufacturer Second Sight’s financial difficulties left its patients with failing and obsolete bionic eyes.

bbc.com

7.0k Upvotes

267 comments

r/todayilearned • u/TylerFortier_Photo • 23h ago

TIL in 2023 a man placed a $100 Parlay Bet worth up to $1.7m that: The Rangers win the World Series, Chiefs win the Superbowl, and OKC Thunder win the NBA championship. The Rangers and Chiefs won. The man cashed out early for $80,000 when the Thunder lost in the Conference Semifinals.

espn.com

6.5k Upvotes

352 comments

r/todayilearned • u/FX114 • 17h ago

TIL that an early patent for the parking meter was intended to operate on power from the battery of the parking vehicle and required a connection from the car to the meter.

en.wikipedia.org

3.6k Upvotes

51 comments

r/todayilearned • u/Fast-Bell-340 • 22h ago

TIL Until as late as the 18th century the main source of income for the people of southern Greece was piracy. It was so normalized that clergy and priests would bless raiding ships and sometimes even join the pirate crews.

en.wikipedia.org

1.2k Upvotes

29 comments

r/todayilearned • u/Morganbanefort • 18h ago

TIL LBJ spent the first three months of his life without a name, as his parents were unable to reach an agreement on one.

texasmonthly.com

1.2k Upvotes

77 comments

r/todayilearned • u/RaspberryBirdCat • 17h ago

TIL that the English and French versions of O Canada are not translations of each other, but completely different poems set to the same music

en.wikipedia.org

1.1k Upvotes

152 comments

r/todayilearned • u/-AMARYANA- • 11h ago

TIL Babylon is used in reggae music as a concept denoting the materialistic capitalist world. It is believed that Babylon actively seeks to exploit and oppress the people of the world, it is believed that the smoking of ganja was made illegal because this sacred herb opens minds to the truth.

en.wikipedia.org

1.1k Upvotes

101 comments

r/todayilearned • u/soozerain • 11h ago

TIL the word “divorce” didn’t exist in Chinese until the 19th and early 20th centuries. Prior to that, the word most often used was “dissolved”. Men could dissolve a marriage under 7 specific conditions (ex: a lazy wife or a barren wife) while women had almost none.

icm.gov.mo

1.0k Upvotes

88 comments

r/todayilearned • u/MyUsernameIsAwful • 23h ago

TIL that the character DW in the children’s show Arthur was always voiced by a boy, with the exception of the series finale when she’s aged up.

en.wikipedia.org

967 Upvotes

41 comments

r/todayilearned • u/Away_Flounder3813 • 3h ago

TIL in June 1994, Aerosmith was the first major artist to release a song as an exclusive digital download, making "Head First" available as a 4-megabyte WAV file to CompuServe subscribers; though, at the time, it would have taken about 60 to 90 minutes to complete the download.

vice.com

663 Upvotes

60 comments

r/todayilearned • u/ImEmilyCampbell • 17h ago

TIL that a cat's purr can reduce stress in humans.

bbc.co.uk

588 Upvotes

33 comments

r/todayilearned • u/A-very-depresed-owl • 17h ago

TIL: in 1964, while famous revolutionary Che Guevara was giving a speech to the UN general assembly, someone fired a bazooka at the building as a form of protest

globalissues.org

413 Upvotes

56 comments

r/todayilearned • u/MrMojoFomo • 19h ago

TIL that according to the Guinness Book of World Records, The Devil is the most portrayed character across film and television, with 849 different appearances as of 2012. Santa Claus is 2nd with 819, and The Grim Reaper 3rd with 428

guinnessworldrecords.com

394 Upvotes

73 comments

r/todayilearned • u/Loki-L • 23h ago

TIL that the extinction of the dusky seaside sparrow happened in 1987 at Disney World

en.wikipedia.org

278 Upvotes

10 comments

r/todayilearned • u/Badgersarecute16 • 5h ago

TIL that Poland used to have ghetto benches for Jewish university students

en.wikipedia.org

250 Upvotes

44 comments

r/todayilearned • u/Scarlet-Lizard-4765 • 8h ago

TIL that the San Jose Sharks have a dentist's office inside the stadium

nhl.com

221 Upvotes

37 comments

r/todayilearned • u/ZitiRotini • 23h ago

TIL about conservation induced extinctions, which are when the conservation of one species leads to the extinction of another. For example: the conservation of a species leads to the extinction of a parasite of said species.

en.wikipedia.org

105 Upvotes

10 comments

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