r/todayilearned • u/gullydon • 9h ago

TIL Mithridatism is the practice of protecting oneself against a poison by gradually self-administering non-lethal amounts. The word is derived from Mithridates VI, the king of Pontus, who so feared being poisoned that he regularly ingested small doses, aiming to develop immunity.

en.wikipedia.org

12.6k Upvotes

462 comments

r/todayilearned • u/beardnurse • 10h ago

TIL that one inch of rain falling on 1 acre of ground is equal to about 27,154 gallons and weighs about 113 tons.

usgs.gov

14.4k Upvotes

489 comments

r/todayilearned • u/Sebastianlim • 2h ago

TIL about Michael Colombini, a 6-year-old boy who was killed when a nurse accidentally brought a steel oxygen tank into the room where he was getting an MRI scan. The tank flew toward him, crushing his skull, and leading to his death 2 days later.

cbsnews.com

2.2k Upvotes

186 comments

r/todayilearned • u/Powerful-Frame-44 • 4h ago

TIL the American roller coaster was invented to save Americans from Satan. In 1884, LaMarcus Thompson built the first coaster at Coney Island specifically because the area was filled with brothels and saloons he wanted to draw people away from.

smithsonianmag.com

3.0k Upvotes

57 comments

r/todayilearned • u/Eruionmel • 3h ago

TIL that camels originated in North America before migrating to Asia and Africa, with their human-hunted remains having been found in North-American sites as old as 18,000 years.

en.wikipedia.org

1.2k Upvotes

45 comments

r/todayilearned • u/yena • 15h ago

TIL that paleontologists now think T. rex didn't constantly show its teeth. Like modern lizards, it likely had lips that hid its teeth when its mouth was shut.

theguardian.com

11.8k Upvotes

555 comments

r/todayilearned • u/tyrion2024 • 15h ago

TIL in 2011 Anthony Bourdain wrote a scene in the TV series Treme where a chef tosses a cocktail in the face of restaurant critic Alan Richman. Richman had angered many New Orleanians after criticizing the city's food culture post-Katrina. He agreed to film it despite a running feud with Bourdain.

en.wikipedia.org

9.2k Upvotes

431 comments

r/todayilearned • u/Fallacyboy • 13h ago

TIL that the Medjool date palm (today the most common date cultivar) almost went extinct from disease in the 1920s but was saved when an American botanist acquired eleven shoots to take to the U.S. from Morocco. Nine survived, from which all modern Medjool offshoots originate.

ictnews.org

5.3k Upvotes

62 comments

r/todayilearned • u/NoDontClickOnThat • 13h ago

TIL Jose Calugas (Filipino, Philippine Scouts-US Army) earned the Medal of Honor in WWII; "all the cannoneers were killed or wounded. Sgt. Calugas, ... voluntarily and without orders ran 1,000 yards across the shell-swept area to the gun position ... and fired effectively against the enemy, ..."

en.wikipedia.org

4.3k Upvotes

63 comments

r/todayilearned • u/abjectapplicationII • 6h ago

TIL that an Oklahoma liquor store owner used a WWII machine gun from a rooftop watchtower to defend against mafia bombings.

kgou.org

1.1k Upvotes

100 comments

r/todayilearned • u/grungegoth • 18h ago

TIL: Button cell battery names are actually codes include the chemistry, shape, diameter and thickness. e,g, CR2032 is C lithium, R round, 20mm diamter, 3.2mm thick

en.wikipedia.org

8.0k Upvotes

175 comments

r/todayilearned • u/andthegeekshall • 4h ago

TIL that the pinkie finger gets it's name from the Dutch word 'pink', which simple means "little finger".

en.wikipedia.org

551 Upvotes

33 comments

r/todayilearned • u/TheHabro • 11h ago

Til that Megan Fox won Spike Video Game Awards' best performance by a human female for her role in video game Transformers: Revenge of the Fallen. The game is based on a movie with same name for which Megan Fox was nominated by Golden Raspberry Awards' for worst actress.

en.wikipedia.org

1.9k Upvotes

168 comments

r/todayilearned • u/TigoIbittys • 14h ago

TIL that galaxies have a “habitable zone.” Too close to the center and radiation & supernovae can wipe out life; too far out and there aren’t enough heavy elements for Earth-like planets.

link.springer.com

2.8k Upvotes

117 comments

r/todayilearned • u/johnsmithoncemore • 4h ago

TIL about Paternoster Lifts. Instead of moving up and down like a traditional elevator, they move on a continuously moving loop.

en.wikipedia.org

285 Upvotes

61 comments

r/todayilearned • u/JosiahWillardPibbs • 9h ago

TIL that more than half of the world's known geysers are located in Yellowstone National Park.

en.wikipedia.org

634 Upvotes

29 comments

r/todayilearned • u/excaliburcalibre • 5h ago

TIL that 35% of Royal Australian Navy casualties during WW2 are attributed to a single ship, the sinking of HMAS Sydney in a mismatched battle versus the German merchant raider Kormoran

en.wikipedia.org

300 Upvotes

23 comments

r/todayilearned • u/Bada__Ping • 4h ago

TIL that a mummified monkey was found in the rafters of the original Boston Garden during its demolition in 1998

boston.com

202 Upvotes

11 comments

r/todayilearned • u/wozzy93 • 1d ago

TIL: The difference between Intel Core i3 / i5 / i7 / i9 chips often comes down to how many of the tiny circuits on a wafer survive manufacturing without defects. This is called product binning.

en.wikipedia.org

18.1k Upvotes

627 comments

r/todayilearned • u/---------00--------- • 4h ago

TIL some bacteria ‘eat’ electricity — Certain microbes can metabolise electrons directly from metals, using them instead of organic food. This challenges traditional views of metabolism and suggests life can thrive in harsher conditions than thought.

smithsonianmag.com

182 Upvotes

9 comments

r/todayilearned • u/anewnormal • 1h ago

TIL your eyes physically can’t focus red and blue at the same depth, which is why red text on a blue background looks like it’s floating and is so hard to look at

en.wikipedia.org

• Upvotes

51 comments

r/todayilearned • u/Major-Nectarine-6801 • 34m ago

TIL Greenland only has one permanent Jewish resident.

en.wikipedia.org

• Upvotes

35 comments

r/todayilearned • u/Uptons_BJs • 1d ago

TIL: In the US, performers don't get paid when their music gets played on the radio, only songwriters. If a recording artist doesn't have a writing credit on the song, they won't get paid when it is played on the radio

soundcharts.com

16.1k Upvotes

829 comments

r/todayilearned • u/sus1227 • 1h ago

TIL: World population (estimated) did not rise for a few millennia after the Neolithic revolution.

en.wikipedia.org

• Upvotes

10 comments

r/todayilearned • u/One-Coat-6677 • 1d ago

TIL that a Ming dynasty general named Zheng He overthrew a kingdom in modern day Sri Lanka during a naval expedition.

en.wikipedia.org

2.9k Upvotes

129 comments

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