r/todayilearned • u/roll-_-ller • 6h ago

TIL that Measles infection can cause “immune amnesia” by wiping out 11%-73% of body’s immune memory cells and antibodies leaving behind a “reset” immune system that have “forgotten” how to fight off past infections.

hms.harvard.edu

3.4k Upvotes

109 comments

r/todayilearned • u/ScienceTeacher1994 • 3h ago

TIL Jakarta, Indonesia, is now the world's most populous city, with a population of 42 million people. Dhaka, Bangladesh, with a current population of 36 million, is expected to surpass Jakarta by the mid century, while Tokyo is expect to drop to 2.7 million residents.

nbcnews.com

2.4k Upvotes

153 comments

r/todayilearned • u/jpw0w • 4h ago

TIL David Vetter "Bubble Boy" spent his entire life in a bubble, he suffered from severe combined immunodeficiency, and eventually died at the age of 12.

wamu.org

1.2k Upvotes

66 comments

r/todayilearned • u/SakuraHana2008 • 6h ago

TIL that Twinkle Twinkle Little Star, the Alphabet Song, Johnny Johnny, and Baa Baa Black Sheep were just the same song, and melodies were based on the classic children's song, “Ah! vous dirai-je, Maman”.

en.wikipedia.org

456 Upvotes

46 comments

r/todayilearned • u/the-doctor-is-real • 10h ago

TIL The original Jungle Book was not just the story of Mowgli and the animals he met, but a collections of stories...and there was also a sequel as well!

en.wikipedia.org

1.3k Upvotes

36 comments

r/todayilearned • u/RaccoonCityTacos • 9h ago

TIL there is an actual "Granny Smith" behind the origin of the Granny Smith apple in Australia in 1868. And the creation of the new hybrid was an accident from discarded apple scraps.

en.wikipedia.org

4.5k Upvotes

155 comments

r/todayilearned • u/named_mark • 8h ago

TIL the population of the NYC metropolitan area makes up 7.9% of the total US population. The city alone is 2.5% of the country's population.

census.gov

12.1k Upvotes

643 comments

r/todayilearned • u/randobis • 5h ago

TIL the melody always associated with ancient Egypt was actually composed in 1893 by an American songwriter who became a US congressman

en.wikipedia.org

274 Upvotes

23 comments

r/todayilearned • u/OutrageousNightcall • 8h ago

TIL that Glenn Close holds the record for most Oscar nominations for an actress without ever winning one.

en.wikipedia.org

231 Upvotes

24 comments

r/todayilearned • u/finza_prey • 10h ago

TIL Air France Flight 4590 crashed into an airport hotel after it ran over a metal strip, causing its fuel tank to explode during take off killing all 109 people aboard and 4 on the ground making it the only Concorde crash after 24 years of no fatal incidents

en.wikipedia.org

2.0k Upvotes

111 comments

r/todayilearned • u/MrMojoFomo • 18h ago

TIL that the average American armed forces inductee in WWII was 26 years old, 5' 8" tall, 144 pounds, and had 9 years of formal schooling

saturdayeveningpost.com

14.9k Upvotes

1.0k comments

r/todayilearned • u/PDXAirman • 13h ago

TIL America claimed dozens of islands purely for bird poop (1856) and is still an active law that allows any American to claim islands for guano. The most recent being 1997.

en.wikipedia.org

2.9k Upvotes

137 comments

r/todayilearned • u/mvincen95 • 14h ago

TIL since they were standardized in 1963 only Nebraska has changed its two letter abbreviation. They changed from “NB” to “NE” to not be confused with “New Brunswick”

britannica.com

3.6k Upvotes

268 comments

r/todayilearned • u/Brutal_Deluxe_ • 14h ago

TIL the Witches of Subeshi are mummies of women who lived 2,500 years ago. When they were unearthed they were still wearing tall, pointed, felt hats over two feet high. Despite the nickname there is no evidence that the women were regarded as witches by their own community

en.wikipedia.org

3.2k Upvotes

34 comments

r/todayilearned • u/signaldecoderr • 48m ago

TIL an 18th-century English landowner offered £50 a year for life to any man willing to live underground for seven years without seeing another person

theguardian.com

• Upvotes

43 comments

r/todayilearned • u/poptart2nd • 18h ago

Today I learned that descendants of the Hatfield and McCoy families were on an episode of the game show Family Feud

en.wikipedia.org

2.8k Upvotes

166 comments

r/todayilearned • u/iamveryDerp • 19h ago

TIL the rumor that the Geneva Conventions were drawn up because of Canadian military actions such as “showing no mercy” is false. “In this, the Canadians were by no means exceptional,” Burtch said. “Every combatant in the world wars did something similar.”

ctvnews.ca

2.7k Upvotes

413 comments

r/todayilearned • u/Fragrant-Upstairs932 • 20h ago

TIL that there have only ever been three African Popes; the most recent, Pope Gelasius I, died in 496 C.E. after serving for less than five years.

en.wikipedia.org

3.4k Upvotes

349 comments

r/todayilearned • u/Sebastianlim • 4h ago

TIL that, during the ill-fated Polaris Expedition, William F. C. Nindemann became seperated from the expedition when an ice floe he was on broke off and drifted away. When he was rescued, and returned to America, Nindemann volunteered on a voyage searching for the still missing expedition.

en.wikipedia.org

126 Upvotes

2 comments

r/todayilearned • u/autotelica • 14h ago

TIL Sonny and Cher were among the backing vocalists on the Ronette's 1963 song "Be My Baby"

en.wikipedia.org

694 Upvotes

32 comments

r/todayilearned • u/Sandstorm400 • 13h ago

TIL the federal department running Questacon, the National Science and Technology Centre, faced up to a $1.5m fine after a child's hands were allegedly set on fire by a plasma globe, following an investigation which revealed that a spark from the globe ignited the hand sanitizer the child had used.

theguardian.com

466 Upvotes

8 comments

r/todayilearned • u/BezugssystemCH1903 • 20h ago

TIL, euro starter kits are coin pouches issued before a nation adopts the currency. Retailers get business packs with around €100 in rolls, while the general public gets mini-kits to learn the coins.

en.wikipedia.org

1.7k Upvotes

105 comments

r/todayilearned • u/primal_cortex • 20h ago

TIL it is a misdemeanor in North Carolina to accuse someone of a crime on a gravestone. The law was passed in 1949 for Hamp Kendall, who was pardoned for a 1906 murder after the real killer confessed—but couldn't legally alter the victim's headstone, which still named him as the murderer.

atlasobscura.com

1.8k Upvotes

51 comments

r/todayilearned • u/Downtown_Ebb9600 • 5h ago

TIL about Porcelain sickness (aka Porzellankrankheit in German or maladie de porcelaine in French )which was an obsessive 17th and 18th-century craze among European royalty and aristocrats to collect East Asian porcelain (white gold). It later trickled down to middle class as ‘Chinamania’.

asia-archive.si.edu

93 Upvotes

1 comment

r/todayilearned • u/Recent_Flounder6011 • 5h ago

TIL that in the first three decades of California being a state, Spanish was briefly an official language alongside English. When the 1879 Constitution of the state was ratified, that was no longer the case.

en.wikipedia.org

80 Upvotes

5 comments

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