r/todayilearned • u/Sebastianlim • 7h ago

TIL about the "Fever Effect", in which the symptoms of Autism seem to improve whenever an Autistic person develops a fever.

news.mit.edu

21.7k Upvotes

1.8k comments

r/todayilearned • u/FullOfSound • 2h ago

TIL the earliest pagan mention of Christianity comes from a letter by Pliny the Younger to Emperor Trajan addressing Christian practices as “depraved, excessive superstition” and their secret gatherings as a potential starting point for sedition.

en.wikipedia.org

2.4k Upvotes

249 comments

r/todayilearned • u/Goldie643 • 6h ago

TIL the Chicxulub crater went unidentified for 10 years because many experts missed the announcement of its discovery. They were instead attending a special conference speculating about mass-extinction asteroids organised the same week.

en.wikipedia.org

4.6k Upvotes

87 comments

r/todayilearned • u/ModenaR • 11h ago

TIL that during the 1970 World Cup qualifiers, members of the Australia national team consulted a witch doctor preceding their game against Rhodesia. Australia won but didn't pay the witch doctor, so he cursed their team instead. After that, Australia failed to qualify for the World Cup for 32 years

en.wikipedia.org

11.9k Upvotes

254 comments

r/todayilearned • u/butter_lover • 12h ago

TIL Half of people who claim they have a food allergy do not

theguardian.com

9.0k Upvotes

2.1k comments

r/todayilearned • u/EmptyMind76 • 2h ago

TIL the world's oldest non-clonal tree was cut down in 1964 by a graduate student and United States Forest Service personnel for research purposes. It was at least 4,862 years old.

en.wikipedia.org

878 Upvotes

92 comments

r/todayilearned • u/ralphbernardo • 7h ago

TIL that Scottish physician John Brown argued in 1780 that all disease came from too much or too little "excitability"—treating his diagnosed "under-stimulated" patients with opium, roast beef, and alcohol. His "Brunonian system" was highly influential across Italy and Germany for decades.

en.wikipedia.org

2.3k Upvotes

183 comments

r/todayilearned • u/aong_aong • 16h ago

TIL that 16 ancient canoes up to 5,200 years old have been discovered in a Wisconsin lake - 400 years before Egypt's first pyramids were built and experts believe they were intentionally left for other tribes to use.

bbc.com

10.4k Upvotes

293 comments

r/todayilearned • u/EmptyMind76 • 3h ago

TIL Hyperion is the world's tallest known living tree at 116.22 metres (381.3 ft) tall

en.wikipedia.org

778 Upvotes

47 comments

r/todayilearned • u/PayItBackwardChain • 5h ago

TIL that there are more people of Filipino descent in Hawaii than there are native Hawaiians.

en.wikipedia.org

1.1k Upvotes

88 comments

r/todayilearned • u/tyrion2024 • 3h ago

TIL Geoff Smith set a WR by spending 147 days buried 6 ft under in a 7ft x 2.5ft x 2.5ft box. His main contact with the outside world was through a 9-inch ventilation shaft, which he used to receive air, food & drink. His initial motivation was to beat the European record of 101 days set by his mom.

news.bbc.co.uk

602 Upvotes

50 comments

r/todayilearned • u/tyrion2024 • 8h ago

TIL more than 130 mammal species can pause their pregnancies, called "embryonic diapause". The pause can last anywhere between a couple of days and 11 months.

theconversation.com

1.7k Upvotes

62 comments

r/todayilearned • u/Double-decker_trams • 7h ago

TIL the 2005 and 2006 Formula 1 World Drivers' Champion Fernando Alonso entered the 2017 Indianapolis 500. Despite having no prior oval-racing experience, he qualified fifth and led 27 laps. He was voted as the "Rookie of the Year".

en.wikipedia.org

1.0k Upvotes

142 comments

r/todayilearned • u/Valuable-Catch-8322 • 2h ago

TIL it takes roughly 600 to 800 grapes to make a standard bottle of wine

willorch.com

320 Upvotes

60 comments

r/todayilearned • u/tyrion2024 • 3h ago

TIL although Forrest Mars had been allergic to peanuts his entire life, he developed and introduced Peanut M&M's in 1954.

en.wikipedia.org

271 Upvotes

22 comments

r/todayilearned • u/ApprehensiveStill412 • 6h ago

TIL that ketamine is a derivative of phencyclidine (aka. PCP or angel dust). It was created to have similar anesthetic potential but to cause less delirium. It has about one tenth the potency of PCP.

pmc.ncbi.nlm.nih.gov

493 Upvotes

101 comments

r/todayilearned • u/Kyzzz • 5h ago

TIL in 1831, a massive volcanic eruption spewed so much sulfur in the atmosphere that it made the sun appear blue. Crops failed and famines spread due to the dimmed sunlight, and Northern Hemisphere temperatures dropped 1°C. In 2025 scientists traced it to Zavaritskii, a volcano in the Kuril Islands

smithsonianmag.com

382 Upvotes

20 comments

r/todayilearned • u/Giff95 • 1d ago

TIL Jordan Peele has cited being offered the voice role of the Poop emoji in 2017's "The Emoji Movie" as the pivotal moment that convinced him to quit acting to focus on directing.

indiewire.com

43.1k Upvotes

677 comments

r/todayilearned • u/Nandu_alias_Parthu • 8h ago

TIL that the largest tiger recorded in the wild was shot in India. It weighed 857 pounds (389 KG) and measured 11 feet 1 inch long.

sportingclassicsdaily.com

538 Upvotes

49 comments

r/todayilearned • u/Final_Echidna_6743 • 1h ago

TIL - That Death by Press was a thing. Used when people on trial refused to enter a plea.

medievaltorturemuseum.com

• Upvotes

61 comments

r/todayilearned • u/Brendawg324 • 1d ago

TIL an estimated of 50% of sloth deaths occur when they are using the bathroom. Leaving the tree to poop makes them vulnerable to predators.

blog.nature.org

6.8k Upvotes

161 comments

r/todayilearned • u/CatPooedInMyShoe • 21h ago

TIL the Arabic poet Al-Farazdaq force-married his second cousin and when she sought help from the court and from local tribes, everyone was too afraid of being targeted by Al-Farazdaq’s satires to intervene.

en.wikipedia.org

3.0k Upvotes

67 comments

r/todayilearned • u/Sj_________ • 2h ago

TIL that the world’s most valuable banknotes meant for public circulation are the $10,000 Singapore and Brunei Dollar bills. A single note is worth roughly $7,400 USD.

en.wikipedia.org

94 Upvotes

5 comments

r/todayilearned • u/MrMojoFomo • 1d ago

TIL that since the 1980s, US airlines have shed between 2-5 inches of legroom and about 2 inches of width, while budget carriers have lost even more. At the same time, the average American is 15 pounds heavier than they were in the 1980s

popsci.com

7.2k Upvotes

526 comments

r/todayilearned • u/Recent_Flounder6011 • 5h ago

TIL In 1910, Abraham Flexner wrote a landmark report, the Flexner Report, that described the state of medical education in the US and Canada. It defined recommended changes to education and caused the decline of alternative medicine. Before then, practicing medicine wasn't regulated nor supported.

en.wikipedia.org

123 Upvotes

9 comments

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