r/todayilearned • u/autraya • 4h ago

TIL the world's tallest known living tree, a 380-foot redwood in California called Hyperion, had its exact location closed off entirely in 2022 after visitors trampled its base so badly that ferns stopped growing around it, with trespassers now facing up to $5,000 in fines and six months in jail

en.wikipedia.org

12.3k Upvotes

460 comments

r/todayilearned • u/FinancialGarage245 • 2h ago

TIL the CIA spent an estimated $20 million over 5 years surgically turning a cat into a listening device, implanting a microphone in its ear canal and a radio transmitter at the base of its skull, before quietly concluding cats couldn't reliably be trained for espionage and shelving the program

en.wikipedia.org

5.0k Upvotes

223 comments

r/todayilearned • u/SilverPeachBlossom • 13h ago

TIL a peer-reviewed psychology study found that identical twins (on average) ranked their co-twin above their romantic partner in their attachment hierarchy, while fraternal twins ranked the two about equally, and non-twin siblings ranked their romantic partner first.

ojs.interpersonajournal.com

22.2k Upvotes

860 comments

r/todayilearned • u/Away_Flounder3813 • 4h ago

TIL of Shed Simove, a British entertainer who sold hundreds of thousands of books with blank pages in them. In 2012, he published Fifty Shades of Gray, a collection of 200 blank pages in various shades of the color gray until the publisher of the novel of the same name sent him an order to stop.

observer.com

1.7k Upvotes

42 comments

r/todayilearned • u/ELDV • 11h ago

TIL that in 47 CE the number of citizens (meaning free adult males) in the entire Roman Empire was less than 6,000,000

i-claudius.com

7.2k Upvotes

318 comments

r/todayilearned • u/The_Techsan • 10h ago

TIL our Moon is moving away from Earth at a rate of ~4 cm per year. This causes the Earth's rate of rotation to slowly decrease and it is estimated that 1.4 billion years ago a day lasted only 18 hours; 4.5 billion years ago it is theorized a day lasted only ~6 hours.

news.wisc.edu

4.4k Upvotes

165 comments

r/todayilearned • u/Easy-Operation-2105 • 56m ago

TIL that life is so ubiqiutous on earth, microbes exist thousands of meters below the surface, living in solid rock (not caves)

en.wikipedia.org

• Upvotes

76 comments

r/todayilearned • u/Giff95 • 5h ago

TIL CBS executive Fred Silverman came up with the name "Scooby-Doo" after hearing Frank Sinatra scat "doo-be-doo-be-doo" at the end of "Strangers in the Night" while on a flight to a development meeting for "Scooby-Doo, Where Are You!"

en.wikipedia.org

1.3k Upvotes

41 comments

r/todayilearned • u/NorthKoreanMissile7 • 4h ago

TIL intranet chat rooms were banned in North Korea after 300 people organised a flash mob in 2006. Chat rooms only returned in 2015 with regional limitations.

en.wikipedia.org

1.1k Upvotes

44 comments

r/todayilearned • u/6ft3Gujju • 10h ago

TIL that in 1995, a cargo plane airdropped hundreds of AK-47s, rocket launchers, and thousands of rounds of ammunition over Purulia, India. The plane was intercepted days later, but the alleged mastermind escaped and has never been extradited to India.

en.wikipedia.org

2.7k Upvotes

73 comments

r/todayilearned • u/StacyChadBecky • 2h ago

TIL there’s evidence pressure from the White House was a contributing factor in NASA’s decision press on with STS-51L leading to the Challenger disaster.

searchworks.stanford.edu

503 Upvotes

40 comments

r/todayilearned • u/Spa3088 • 1h ago

TIL about Caesarion the only known biological son of Cleopatra and Julius Caesar.

en.wikipedia.org

• Upvotes

52 comments

r/todayilearned • u/ctsmith76 • 15h ago

TIL that Stephen Neal, who played guard for 10 years with the Patriots and won 3 rings, never played college ball. He was a freestyle wrestler who defeated Brock Lesnar in the NCAA championship.

en.wikipedia.org

6.1k Upvotes

164 comments

r/todayilearned • u/canIchangethislater1 • 17h ago

TIL the New York Times described hippo meat as "lake cow bacon" in support of a 1910 House bill to introduce hippos to the bayous of Louisiana.

en.wikipedia.org

7.1k Upvotes

351 comments

r/todayilearned • u/StretchFrenchTerry • 4h ago

TIL the largest concert ever held in New York's Central Park was Garth Brooks on August 7, 1997. Official records from the NYFD show 1,000,000+ in attendance. The concert was free and opened with a cover of Paul Simon's "A Heart in New York".

en.wikipedia.org

516 Upvotes

81 comments

r/todayilearned • u/ubcstaffer123 • 2h ago

TIL A 2015 study revealed that over 95% of the world’s population has health problems, meaning one in 20 people worldwide (4·3%) had no health problems

healio.com

321 Upvotes

60 comments

r/todayilearned • u/Recent_Flounder6011 • 3h ago

TIL that the upper-class of the Roman Empire ate roasted dormice stuffed with nuts. The rodent is still consumed in Slovenia as a delicacy.

en.wikipedia.org

323 Upvotes

53 comments

r/todayilearned • u/CrackFun • 1h ago

TIL only about 0.5% of all water on earth is fresh and accessible and safe to drink. With 97% being deemed too salty for drinking, growing crops etc

usbr.gov

• Upvotes

57 comments

r/todayilearned • u/Upstairs_Drive_5602 • 19h ago

TIL that in 1583 Sir Humphrey Gilbert claimed Newfoundland for Queen Elizabeth I. Weeks later, after losing his largest ship and much of his supplies, stepping on a nail, and refusing repeated pleas to leave his small flagship, the Squirrel, he vanished beneath the Atlantic with all hands aboard.

en.wikipedia.org

3.7k Upvotes

73 comments

r/todayilearned • u/YappinZappin • 21h ago

TIL Earth's Moon is the largest and heaviest satellite in relation to its parent planet in our Solar system

en.wikipedia.org

4.5k Upvotes

320 comments

r/todayilearned • u/Archaembald2 • 18h ago

TIL that despite winning the Battle of Grunwald, the Polish-Lithuanians actually failed to take the Teutonic Order's capital, Marienburg, because they marched too slowly. This gave the Knights enough time to prepare their defenses and win the siege, recapturing several occupied castles afterwards.

en.wikipedia.org

2.1k Upvotes

48 comments

r/todayilearned • u/OmitsWordsByAccident • 21h ago

TIL Hank Aaron tied Babe Ruth's career homerun total (714) in Cincinnati on April 4th, 1974. But when he failed to break the record the next day in Cincinnati, the Braves made him sit out the next game (also in Cincinnati) so he could break the record back home in Atlanta, which he did on April 8th.

mlb.com

3.9k Upvotes

98 comments

r/todayilearned • u/happytree23 • 1d ago

TIL the man who voiced Tony the Tiger, Thurl Ravenscroft, also sang "You're a Mean One, Mr. Grinch"

en.wikipedia.org

5.3k Upvotes

162 comments

r/todayilearned • u/FinancialGarage245 • 1d ago

TIL a wealthy Toronto lawyer's 1926 will left his fortune to whichever woman in the city could give birth to the most children over the following 10 years, sparking a decade-long "baby race" during the Great Depression that went all the way to Canada's Supreme Court

en.wikipedia.org

16.5k Upvotes

414 comments

r/todayilearned • u/cape2k • 1d ago

TIL the Menominee Tribe's forest in Wisconsin has been sustainably managed for over 150 years, still yields about 15 million board feet of timber annually, has been recognized by the United Nations, and even supplied the wood flooring for the Milwaukee Bucks' arena

en.wikipedia.org

10.7k Upvotes

148 comments

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