52 of the most interesting things I learned in 2020:

1. The bacteria RB41 is known to exist in only three places: showerheads, dog noses, and paleolithic cave paintings.

*The Great Indoors* https://amzn.to/3aSWBiq 
2. An average pair of jeans requires 6 miles of thread. In the not-too-distant past, it would have taken 110 hours to spin this much fabric. The time cost of clothing meant owning lots of clothes = extravagant wealth.

*The Fabric of Civilization* https://amzn.to/3hlXfWX 
3. Cities with public libraries in the early 20th century had patenting rates 8–13% higher by the end of the century.

“Knowledge Access: The Effects of Carnegie Libraries on Innovation”
5. Tractors transformed American agriculture during the 20th century:

- replaced 23 million draft animals
- increased cropland 79 million acres
- 956,000 farms gone
- 1.7 million farm jobs replaced by machines https://www.nber.org/papers/w7947 
6. In the 1860s, half of all fish caught in British waters and one-sixth of all potatoes grown in Britain were consumed in the form of fish and chips.

*Cuisine and Empire* https://amzn.to/3hmBpmh 
9. In the mid-1960s, one in twenty-seven adult women in Spain was a prostitute.

*The New Spaniards* https://amzn.to/3mPYxur 
11. Blowing out candles on a birthday cake increases the bacteria content on it by up to 1,400 percent.

*The Body* https://amzn.to/3mTS5mc 
12. Raising your body temperature 3 to 4 degrees—getting a fever—to fight off microbes comes with a 20% increase in energy requirements.

*The Body* https://amzn.to/3mTS5mc 
13. You’re more likely to die if it’s the surgeon’s birthday.

14. Passionate kissing results in the transfer of 1 billion bacteria... along with “0.7 milligrams of protein, 0.45 milligrams of salt, 0.7 micrograms of fat, and 0.2 micrograms of ‘miscellaneous organic compounds.'”

*The Body* https://amzn.to/3mTS5mc 
15. In sixth century Teotihuacán (near present-day Mexico City), it was both legal and socially permissible for old women—and only old women—to get drunk in public.

*Cuisine and Empire* https://amzn.to/3hmBpmh 
19. Interest rates have been steadily declining for 700 years, from an average rate of 15% in 1310 to near 0% in 2018.

https://www.bankofengland.co.uk/-/media/boe/files/working-paper/2020/eight-centuries-of-global-real-interest-rates-r-g-and-the-suprasecular-decline-1311-2018.pdf [PDF]
20. It was popular to wear a hat and cape in Spain until 1766, because it made it easier to escape the scene of a crime without being seen.

They went out of style after the king selected them as the uniform of the executioners.

*Goya* https://amzn.to/3mPZNOb 
24. Despite the numerous benefits, being bilingual does not, in fact, make you smarter.

https://owenlab.uwo.ca/pdf/2020%20-%20Nichols%20-%20Assoc%20for%20psych%20science.pdf [PDF]
25. The crawling-through-air-vents-to-another-part-of-a-building trope in film first appeared in 1963 in Dr. No. https://twitter.com/TheCromulentMan/status/1255671668795555841
27. On Tinder, men swipe right (i.e., like) on 60% of women’s profiles, while women swipe right on only 4% of men’s profiles. https://twitter.com/robkhenderson/status/1294628071174213635
28. You need silence to be productive.

A 10-decibal increase in background noise causes productivity to drop by about 5%.

https://joshuatdean.com/wp-content/uploads/2019/01/NoiseCognitiveFunctionandWorkerProductivity.pdf [PDF]
30. In India in the 1970s, young men would carry around boomboxes and play loud music in public.

The trend became less popular after the government began giving away free boomboxes to anyone who got a vasectomy.

*Codes of the Underworld* https://amzn.to/3poAxjS 
31. Blockbuster made so much money on late fees that when they removed them in 2007 to compete with Netflix, they lost half of their profits.

33. Streetlights reduce nighttime crime by 36% and reduce “serious offending” by 4%.

This is roughly the same reduction in crime you would expect from a 10% increase in policing. https://www.nber.org/papers/w25798 
34. The relationship between the Road Runner and the Coyote was governed by a strict set of 9 rules, such as “No outside force can harm the Coyote—only his own ineptitude or the failure of Acme products.” https://twitter.com/lebas_janney/status/1269776188517556225
36. The more time a city spent on the frontier of the American west, the more likely (slightly) the residents of that city today vote Republican, pay lower property taxes, and give their children unique names.

38. Children born to first-cousin marriages have roughly the same increased risk of genetic abnormality as children born to women who are 41 years old instead of 30 years old. https://www.discovermagazine.com/health/go-ahead-kiss-your-cousin
40. People get in car accidents roughly once every 0.5 million miles, according to the National Highway Traffic Safety Administration, compared to once every 4.34 million miles for Teslas driven on autopilot.

https://ir.tesla.com/static-files/47313d21-3cac-4f69-9497-d161bce15da4 [PDF]
41. Technically, planets don’t orbit the sun. Instead, all mass orbits the barycenter.

Though the sun contains 99.8% of the solar system’s mass, Jupiter contains most of the other 0.2%, and it’s enough to bump the sun out of the barycenter. https://twitter.com/physicsJ/status/1279082929566572545
44. Sorting email into folders wastes an average of 67 hours per year.

45. As of 2018, legalized marijuana in the United States has led to a 17% decline in gun-related homicides in Mexico, compared to the years 1996–2017.

https://www.colorado.edu/economics/sites/default/files/attached-files/20-06_-_swanson.pdf [PDF]
47. 92% of top ten Billboard songs refer to sex, with an average of 10.49 reproductive phrases per song.

90% of them are made by males at their peak years of reproductive activity.

*Music: A Subversive History* https://amzn.to/2KYbTHU 
50. In the city blocks surrounding the United Nations headquarters in New York City, most of the parking tickets issued to diplomats go to diplomats from countries with high rates of corruption.

https://www0.gsb.columbia.edu/mygsb/faculty/research/pubfiles/4140/fisman_corruption.pdf [PDF]
51. Trees evolved 360 million years ago, but the fungi that decompose them didn’t evolve until 300 million years ago—leaving a 60-million-year gap for dead plant matter to pile up.

Today, we mine this ancient carbon matter as coal.

*Symphony in C* https://amzn.to/2KDQILw 
52. The wisdom of the crowd—the idea that the average opinion from an uninformed group of people is more likely to be correct than the opinion from a single expert—works even when the crowd is drunk.

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