r/todayilearned • u/geosunsetmoth • 4h ago

TIL that "Necroprinting" is the practice of building 3D printers using the mouth of a dead mosquito as a nozzle, producing results that are better than commercially available printers

science.org

11.9k Upvotes

665 comments

r/todayilearned • u/Acrobatic-Post9811 • 9h ago

TIL about Ruby the painting elephant. When her keepers at the Phoenix Zoo saw her scratching in the dirt with a stick, they gave her a brush and paints. For 3 years, zookeepers did not publicize the knowledge that Ruby could paint. Eventually her paintings were sold to raise money for conservation.

en.wikipedia.org

21.1k Upvotes

413 comments

r/todayilearned • u/Master-Incident9198 • 8h ago

TIL humans are 66% monogamous, putting us ahead of chimps (4%) and gorillas (6%) but far behind the California deermouse with 100% monogamy

bbc.com

11.7k Upvotes

382 comments

r/todayilearned • u/Kyzzz • 8h ago

TIL reggae singer Shaggy, known for "Boombastic", developed his signature singing voice as a US Marine by mimicking his drill instructors. He sang his first hit "Oh Carolina" in that voice because he thought it sounded cool, and when it blew up he realized he'd have to sing every song that way

npr.org

12.8k Upvotes

407 comments

r/todayilearned • u/molondim • 4h ago

TIL: New Zealand has the highest youth suicide rate in the developed world

bbc.com

4.0k Upvotes

739 comments

r/todayilearned • u/ralphbernardo • 10h ago

TIL Steve Jobs’ design obsession went so deep he demanded Apple computers look perfect on the inside. Inspired by Zen Buddhism and Bauhaus minimalism, he believed in “deep simplicity,” and insisted that even the hidden internal engineering look as polished as the outside.

smithsonianmag.com

20.1k Upvotes

1.5k comments

r/todayilearned • u/Ok_Employer7837 • 3h ago

TIL that the secret recipe for the Chartreuse liqueur (made by the monks of the Carthusian order in France) starts with a mixture of 130 herbs. The long list of specific ingredients is known only to two monks at any given time.

en.wikipedia.org

2.9k Upvotes

179 comments

r/todayilearned • u/BackgroundFloyd • 6h ago

TIL a man murdered a secretary at the American Physical Society in 1952 because the organization refused to publish his paper arguing that electrons don't exist.

statmodeling.stat.columbia.edu

4.0k Upvotes

185 comments

r/todayilearned • u/dgusn • 1h ago

TIL Michael Jackson's final public concert was held in New York City on September 10, 2001, just one day before the 9/11 attacks.

en.wikipedia.org

• Upvotes

132 comments

r/todayilearned • u/Mors_Acerba • 5h ago

TIL Pablo Escobar dropped out of highschool twice. Despite that, he forged a highschool degree and managed to enter university with the goal of becoming a criminal lawyer and hoping to eventually enter politics

en.wikipedia.org

2.5k Upvotes

104 comments

r/todayilearned • u/TheQuarantinian • 10h ago

TIL a very humbled Japanese company filmed a TV ad e pressing their sincere apologies - including a synchronized bow of contrition - for having to raise their price 10 Yen (about 9 cents) after 25 years

en.clickpetroleoegas.com.br

2.9k Upvotes

144 comments

r/todayilearned • u/MyOtherRideIsTheRoci • 5h ago

TIL about Francis Henning, a counterfeiter who was apprehended after minting $26K worth of fake nickels. Henning had spent $6800 ($120K adjusted for inflation) on the nickel/copper alloy and only recouped $5K. "Henning Nickels" now sell for hundreds of dollars.

coinweek.com

1.0k Upvotes

53 comments

r/todayilearned • u/AmmianusMarcellinus • 11h ago

TIL a group of Australian socialists tried to build a utopian “New Australia” colony in Paraguay in the 1890s. It collapsed after infighting, strict rules, and culture shock.

abc.net.au

3.1k Upvotes

256 comments

r/todayilearned • u/bawlhie62a2 • 2h ago

TIL about the Cave of Dogs near Naples, Italy, a morbid tourist attraction dating to antiquity. Guides knocked out dogs with volcanic CO2 gas then revived them by throwing them into a lake. This was repeated so often that dogs became anxious wrecks and were put down within months.

en.wikipedia.org

511 Upvotes

65 comments

r/todayilearned • u/Mannzis • 15h ago

Til about the Dirlewanger Brigade. It was a Nazi unit that was so sadistic & depraved that other Nazis considered them over the top. They avoided being disbanded, despite multiple investigations & Nazi officers filing complaints against them.

en.wikipedia.org

6.6k Upvotes

253 comments

r/todayilearned • u/bnrshrnkr • 4h ago

TIL there was a pandemic of Encephalitis lethargica, or sleeping sickness, which began in 1915 and ended abruptly in 1927. The causes of the illness, and the reasons for its sudden disappearance, remain unknown.

en.wikipedia.org

495 Upvotes

40 comments

r/todayilearned • u/PayItBackwardChain • 1h ago

TIL that in 1956-57, Chairman Mao launched the “Hundred Flowers Campaign” where citizens could offer criticism and advice to the government. The criticism was so fierce that the campaign was cancelled, and hundreds of thousands of people who had complained were imprisoned.

en.wikipedia.org

• Upvotes

32 comments

r/todayilearned • u/anganeonnumilla • 15h ago

TIL that 75% of global tiger population lives in India.

en.wikipedia.org

2.7k Upvotes

197 comments

r/todayilearned • u/Xerxes2004 • 19h ago

TIL that at the time of the American Revolution in 1776, the American Bison could still be found in the wild as far east as Pennsylvania, West Virginia, and Georgia.

allaboutbison.com

3.9k Upvotes

145 comments

r/todayilearned • u/Brendawg324 • 23h ago

TIL Nathan’s Famous founder Nathan Handwerker sold hot dogs for 5¢ to undercut a competitor. When customers became suspicious of the low price, he had men in doctors’ coats eat at his stand to make the food seem trustworthy.

en.wikipedia.org

8.8k Upvotes

146 comments

r/todayilearned • u/altrightobserver • 20h ago

TIL about the "cat hair mustache" puzzle from the 1999 game "Gabriel Knight 3: Blood of the Sacred, Blood of the Damned." The player must get cat hair for a mustache by making a trap with tape, a spray bottle, and a shed door. One writer claimed it partly caused the decline in the adventure genre.

en.wikipedia.org

4.7k Upvotes

419 comments

r/todayilearned • u/Karthak_Maz_Urzak • 1d ago

TIL about the Lavender Scare, a moral panic about homosexual people in the United States government which led to their mass dismissal from government service during the mid-20th century. It contributed to and paralleled McCarthyism and the Second Red Scare.

en.wikipedia.org

14.1k Upvotes

353 comments

r/todayilearned • u/TheFrederalGovt • 1d ago

TIL 53 years after achieving the Triple Crown of Horse Racing, Secretariat still holds the record for fastest time in each of the three races.

en.wikipedia.org

8.4k Upvotes

325 comments

r/todayilearned • u/PinkOneHasBeenChosen • 3h ago

TIL that during the non-breeding season, common swifts fly almost continuously for months.

en.wikipedia.org

106 Upvotes

5 comments

r/todayilearned • u/sharkcutter • 1h ago

TIL that the first flag of the United States had the British union flag in the top left corner as a demonstration of loyalty to King George III

en.wikipedia.org

• Upvotes

4 comments

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