# Today I learned **URL:** \ **Category:** General\ **Created:** [January 19, 2021, 10:46pm UTC](https://community.goactuary.com/t/today-i-learned/1835 "2021-01-19T22:46:38Z")\ **Posts on this page:** 20\ **Page:** 108
**Author:** ![dr\_t\_non-fan](https://community.goactuary.com/letter_avatar_proxy/v4/letter/d/a8b319/32.png) [@dr\_t\_non-fan](https://community.goactuary.com/u/dr_t_non-fan)\ **Post date:** [December 16, 2024, 8:09pm UTC](https://community.goactuary.com/t/today-i-learned/1835/2152 "2024-12-16T20:09:10Z")
> [@knoath](#): > > Crocodile Dundees are very rare, almost mythical. I saw one in a documentary. TWO documentaries!! ---
**Author:** ![Actuary321](https://community.goactuary.com/letter_avatar_proxy/v4/letter/a/ed8c4c/32.png) [@Actuary321](https://community.goactuary.com/u/Actuary321)\ **Post date:** [December 16, 2024, 10:54pm UTC](https://community.goactuary.com/t/today-i-learned/1835/2153 "2024-12-16T22:54:06Z")
Presbyopia comes from the same root as Presbyterian. The Presby part meaning “old men” because Presbyterians are governed by the elders of the church. And Presbyopia is “old men eyesight.” > **Presbyopia** > > Makes it difficult to see things up close. This condition occurs when the eye’s lens hardens and the focusing muscle weakens, making it harder to focus on nearby objects. Presbyopia typically develops around age 40. ---
**Author:** ![dr\_t\_non-fan](https://community.goactuary.com/letter_avatar_proxy/v4/letter/d/a8b319/32.png) [@dr\_t\_non-fan](https://community.goactuary.com/u/dr_t_non-fan)\ **Post date:** [December 17, 2024, 9:38pm UTC](https://community.goactuary.com/t/today-i-learned/1835/2154 "2024-12-17T21:38:55Z")
Farmers use GPS. Unfortunately, solar storms affect their GPS’es: > **[Extreme solar storm turned GPS-reliant tractors into demonic machines](https://interestingengineering.com/space/solar-storm-tractors-demonic-machines)** > > Solar storms interfere with GPS by releasing charged particles, which can cause tractors to come to an unexpected halt, veer off course. ---
**Author:** ![1695814](https://community.goactuary.com/user_avatar/community.goactuary.com/1695814/32/38506_2.png) [@1695814](https://community.goactuary.com/u/1695814)\ **Post date:** [December 17, 2024, 10:19pm UTC](https://community.goactuary.com/t/today-i-learned/1835/2155 "2024-12-17T22:19:08Z")
> [@dr\_t\_non-fan](#): > > solar storms affect their GPS’es: I believe the plural is GPI. ---
**Author:** ![Actuary321](https://community.goactuary.com/letter_avatar_proxy/v4/letter/a/ed8c4c/32.png) [@Actuary321](https://community.goactuary.com/u/Actuary321)\ **Post date:** [December 28, 2024, 5:44pm UTC](https://community.goactuary.com/t/today-i-learned/1835/2156 "2024-12-28T17:44:54Z")
Nicomachus’s Theorem that the sum of the cubes of the first n natural numbers is equal to the square of the sum of those numbers. And that 2025 is the answer for the first 9 numbers. ---
**Author:** ![NormalDan](https://community.goactuary.com/user_avatar/community.goactuary.com/normaldan/32/1013_2.png) [@NormalDan](https://community.goactuary.com/u/NormalDan)\ **Post date:** [January 2, 2025, 7:18pm UTC](https://community.goactuary.com/t/today-i-learned/1835/2157 "2025-01-02T19:18:25Z")
The 45th president is returning to the office in the year 45^2 ---
**Author:** ![Mathman](https://community.goactuary.com/user_avatar/community.goactuary.com/mathman/32/14042_2.png) [@Mathman](https://community.goactuary.com/u/Mathman)\ **Post date:** [January 2, 2025, 7:45pm UTC](https://community.goactuary.com/t/today-i-learned/1835/2158 "2025-01-02T19:45:41Z")
TIL about the California cooler: > **[California cooler (cabinet)](https://en.wikipedia.org/wiki/California_cooler_(cabinet))** > > A California cooler, also known as a cooler cabinet, is a type of cabinet used for the cool storage of food items that was popular in the western United States in the late 19th and early 20th centuries. The California cooler is constructed simply as an interior cabinet with slatted or screened shelves. Vents near the top and bottom allow outside air to circulate by the principle of natural convection. This results in convective cooling, which keeps perishable food items fresh. The outside vents a... ---
**Author:** ![Actuary321](https://community.goactuary.com/letter_avatar_proxy/v4/letter/a/ed8c4c/32.png) [@Actuary321](https://community.goactuary.com/u/Actuary321)\ **Post date:** [January 2, 2025, 7:57pm UTC](https://community.goactuary.com/t/today-i-learned/1835/2159 "2025-01-02T19:57:47Z")
Yeah, the sum of the first 9 natural numbers is 45 and 45^2 = 2025 and that is also the sum of the cubes of the first 9 natural numbers. 🙂 ---
**Author:** ![ArthurItas](https://community.goactuary.com/user_avatar/community.goactuary.com/arthuritas/32/63_2.png) [@ArthurItas](https://community.goactuary.com/u/ArthurItas)\ **Post date:** [January 2, 2025, 8:59pm UTC](https://community.goactuary.com/t/today-i-learned/1835/2160 "2025-01-02T20:59:29Z")
Hmm, I always thought a California cooler was something else entirely > **[The Weird and Wavy History of Wine Coolers](https://www.vice.com/en/article/the-weird-and-wavy-history-of-wine-coolers/)** > > The bodacious bottled drinks once saw an explosion in popularity, then a backlash, and now, a surprise comeback. ---
**Author:** ![Mathman](https://community.goactuary.com/user_avatar/community.goactuary.com/mathman/32/14042_2.png) [@Mathman](https://community.goactuary.com/u/Mathman)\ **Post date:** [January 2, 2025, 9:01pm UTC](https://community.goactuary.com/t/today-i-learned/1835/2161 "2025-01-02T21:01:16Z")
I saw the wiki article when I googled it, I hadn’t heard of this California cooler either! ---
**Author:** ![soyleche](https://community.goactuary.com/user_avatar/community.goactuary.com/soyleche/32/42_2.png) [@soyleche](https://community.goactuary.com/u/soyleche)\ **Post date:** [January 2, 2025, 10:52pm UTC](https://community.goactuary.com/t/today-i-learned/1835/2162 "2025-01-02T22:52:01Z")
That’s a general relationship 1^3 + 2^3 + … + n^3 = (1 + 2 + … + n)^2 ---
**Author:** ![Actuary321](https://community.goactuary.com/letter_avatar_proxy/v4/letter/a/ed8c4c/32.png) [@Actuary321](https://community.goactuary.com/u/Actuary321)\ **Post date:** [January 2, 2025, 10:57pm UTC](https://community.goactuary.com/t/today-i-learned/1835/2163 "2025-01-02T22:57:57Z")
Yeah, I posted that a couple posts earlier, which got no likes or responses. Nicomachus’s Theorem ---
**Author:** ![dr\_t\_non-fan](https://community.goactuary.com/letter_avatar_proxy/v4/letter/d/a8b319/32.png) [@dr\_t\_non-fan](https://community.goactuary.com/u/dr_t_non-fan)\ **Post date:** [January 2, 2025, 11:11pm UTC](https://community.goactuary.com/t/today-i-learned/1835/2164 "2025-01-02T23:11:59Z")
Is there a simple proof for this? I guess I can use Mathematical Induction. Or this fancy picture: ![image](https://community.goactuary.com/uploads/default/original/3X/7/b/7bcc38a5cb5bf83119d3deba2255e2be8f86b5d8.png) ---
**Author:** ![3rookie](https://community.goactuary.com/letter_avatar_proxy/v4/letter/3/e0b2c6/32.png) [@3rookie](https://community.goactuary.com/u/3rookie)\ **Post date:** [January 3, 2025, 5:46am UTC](https://community.goactuary.com/t/today-i-learned/1835/2165 "2025-01-03T05:46:58Z")
Those are some nice Montessori blocks ---
**Author:** ![twig93](https://community.goactuary.com/user_avatar/community.goactuary.com/twig93/32/527_2.png) [@twig93](https://community.goactuary.com/u/twig93)\ **Post date:** [January 4, 2025, 6:30pm UTC](https://community.goactuary.com/t/today-i-learned/1835/2166 "2025-01-04T18:30:32Z")
![image](https://community.goactuary.com/uploads/default/original/3X/0/5/05c2252aa2cb41412af37c5391608826d5671437.jpeg) Confirmed by this article: [https://bestdiplomats.org/oldest-zoos-in-the-us/#:~:text=List%20of%20the%2010%20Oldest,Largest%20Zoo%20in%20the%20World](https://bestdiplomats.org/oldest-zoos-in-the-us/#:~:text=List%20of%20the%2010%20Oldest,Largest%20Zoo%20in%20the%20World)? The building and the zoo itself celebrate their sesquicentennial this year. ---
**Author:** ![vjvj](https://community.goactuary.com/user_avatar/community.goactuary.com/vjvj/32/406_2.png) [@vjvj](https://community.goactuary.com/u/vjvj)\ **Post date:** [January 5, 2025, 12:08am UTC](https://community.goactuary.com/t/today-i-learned/1835/2167 "2025-01-05T00:08:08Z")
Nice claim to fame. Up until now, the only thing I’d ever heard about the zoo was that it housed the last known passenger pigeon and the last known Carolina parakeet. I looked it up to make sure I didn’t remember wrong, and learned this interesting extinction fact - after the pigeon went extinct in its cage at the Cincinnati zoo, they moved the parakeet into that same cage. So two species went extinct in that same cage. ---
**Author:** ![twig93](https://community.goactuary.com/user_avatar/community.goactuary.com/twig93/32/527_2.png) [@twig93](https://community.goactuary.com/u/twig93)\ **Post date:** [January 5, 2025, 1:18am UTC](https://community.goactuary.com/t/today-i-learned/1835/2168 "2025-01-05T01:18:16Z")
Wow, that’s sad. They’re one of the better zoos out there. The Cincinnati Bengals derived their name from the Bengal tigers recently (then) acquired by the zoo. They’re also known for having to shoot their silverback gorilla, Harambe, after a kid got into the enclosure. And more happily for miraculously saving the life of Fiona, an _extremely_ premature baby hippo turned social media star. ---
**Author:** ![tommie.frazier](https://community.goactuary.com/letter_avatar_proxy/v4/letter/t/b5a626/32.png) [@tommie.frazier](https://community.goactuary.com/u/tommie.frazier)\ **Post date:** [January 5, 2025, 2:54am UTC](https://community.goactuary.com/t/today-i-learned/1835/2169 "2025-01-05T02:54:15Z")
> [@twig93](#): > > They’re also known for having to shoot their silverback gorilla, Harambe, May he RIP. ---
**Author:** ![Actuary321](https://community.goactuary.com/letter_avatar_proxy/v4/letter/a/ed8c4c/32.png) [@Actuary321](https://community.goactuary.com/u/Actuary321)\ **Post date:** [January 5, 2025, 3:19am UTC](https://community.goactuary.com/t/today-i-learned/1835/2170 "2025-01-05T03:19:33Z")
didn’t we have a RIP thread for him on the AO? ---
**Author:** ![twig93](https://community.goactuary.com/user_avatar/community.goactuary.com/twig93/32/527_2.png) [@twig93](https://community.goactuary.com/u/twig93)\ **Post date:** [January 5, 2025, 3:36am UTC](https://community.goactuary.com/t/today-i-learned/1835/2171 "2025-01-05T03:36:51Z")
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