52 things I learned in 2021

Here are some of the most interesting things I learned this year:

1. The healthier version of Quaker’s Apple Cinnamon Instant Oatmeal claims to contain 35% less sugar, but that’s only because the packaging is smaller. The sugar-per-unit is the same as the oatmeal in the regular-sized package. (“Quaker Oats boast 35 percent less sugar, actually just a smaller packet”)
2. When the company pays for your flight, you spend 7% more for the same ticket than if you paid out of pocket. You’re also willing to pay 8% more for a flight if it gets you into the next status tier. (“Reaching for Gold: Frequent-Flyer Status Incentives and Moral Hazard”)
3. Not a single baby born in Britain in 2020 was named Nigel. There were also no Karens, though 15 babies were named Lucifer. (Harry Wallop)
4. 7% of American men think they could beat a grizzly bear in a fight. 71% also think they would win against a goose, though rates are higher in the American South. (YouGov)
5. Screen time is actually not that bad for kids. The negative effect on well-being is roughly the same as making them eat potatoes against their will. (“The association between adolescent well-being and digital technology use”)
6. After Gutenberg invented the printing press, the price of books fell an average of 2.4% per year every year for 100 years straight. (“Gutenberg’s moving type propelled Europe towards the scientific revolution”)
   
   
   
7. Though James Bond cheats death in some pretty spectacular ways, the thing most likely to eventually kill him is acute diarrhea. In the 86 international trips he took between 1962 and 2021, he washed his hands only twice. (During this period, he also had 59 sexual liaisons, with an average elapsed time of 20 minutes between first encounter and intercourse. His partners have a mortality rate of 27.1%.) (“No time to die: An in-depth analysis of James Bond’s exposure to infectious agents”)
8. When you talk with someone, you subconsciously imitate their facial expressions. Even more incredible: blind people do, too! (“Facial mimicry in the congenitally blind”)
9. The moon is slowly drifting away from Earth. In 600 million years from now, the earth will experience its last total solar eclipse. (“The Moon Is Leaving Us”)
10. The average car speed in Manhattan is 4.7 mph. (“A Congestion-aware Routing Scheme for Autonomous Mobility-on-Demand Systems”) The average walking pace in Manhattan is 8.2 mph. (“The Pace of Life in 31 Countries”)
11. A group of ferrets is called a business. (YourDictionary.com)
12. Jews in Spain and in parts of Latin America celebrate the Festival of Santa Esterica, which is a made-up holiday from the sixteenth century. During the Spanish Inquisition, Jews were banned from celebrating Purim. In response, they left Purim intact, but just renamed it the Festival of Santa Esterica, hoping the Inquisitor’s wouldn’t notice—since there were already more holy days and festivals in the Catholic Church than most people could keep track of. The Inquisitors never noticed—but neither did later generations: Jews in parts of Spain and Latin America still celebrate the made-up festival today. (Wikipedia, via Scott Alexander)
13. Languages are more likely to develop a word for blue when their speakers 1) live near lakes, 2) live in darker places (usually farther north), and 3) live in a large society. (“Sunlight affects whether languages have a word for ‘blue'”)
14. Farmers have hunted wolves to near-extinction in areas where they kill livestock. But when wolves are re-introduced, deer–vehicle collisions drop by 24%, producing a net economic benefit 63 times greater than the amount lost from lost livestock. (“Wolves make roadways safer, generating large economic returns to predator conservation”)
    
    
    
15. Women’s salaries go up 4.4% in the first year after their manager has a baby—but only if the manager is male, and only if the baby is a girl. (“Daddy’s girl: Daughters, managerial decisions, and gender inequality”)
16. Newark police officers did not fire a single shot during 2020. (“Newark cops, with reform, didn’t fire a single shot in 2020”, via Tyler Cowen)
17. By the year 2100, there will be enough carbon in the atmosphere for new minerals to form. The first will be Nahcolite, which requires 680 parts per million of CO₂. For comparison, during the last ice age, CO₂ concentration was 200ppm; in 1700 it was 280ppm; today it’s 419ppm. (“Nahcolite and Trona”)
18. People like reading about themselves You like reading about yourself: 26% of all highlighted Kindle passages contain “you” language⁠—more than “we,” “one,” and “people” passages combined. (“‘You’ speaks to me”)
19. Though some people still question whether humans are responsible for climate change, it is certain that humans have caused temperatures to rise on the moon. The dust kicked up from the Apollo missions raised local temperatures as much as 2°C. (“Examination of the Long-Term Subsurface Warming Observed at the Apollo 15 and 17 Sites…”)
20. There are 10–15% more same-sex couples in counties that had gold rushes than counties that didn’t. It’s not because these counties are more liberal. It’s the typical male-to-female ratios of seven-to-one during gold rushes produced sexual norms that persist 150 years later. (“Institutions, attitudes and LGBT: Evidence from the gold rush”)
21. When college students take a required course that starts at 7:30am, they are 10% less likely to major in that subject, compared to students who take the same class later in the day. (“Attribution bias in major decisions”)
22. Chilean sea bass became a popular menu item at upscale restaurants only as recently as the late 1980s after the fish was renamed by a clever marketer in Los Angeles. Previously, it was known as the Patagonian toothfish. (The Outlaw Ocean: Journeys Across the Last Untamed Frontier)
    
    
23. Couples who spend between $2,000 and $4,000 on an engagement ring are 1.3 times more likely to divorce compared to couples who spend less than $2,000. Weddings with big guest lists also produce marriages with lower divorce rates. (“‘A Diamond is Forever’ and Other Fairy Tales”) Couples who marry on Valentine’s Day are also more likely to divorce: 45% more likely by their third anniversary, 41% more likely by their fifth anniversary, and 36% more likely by their ninth anniversary. (“Not Your Lucky Day”)
24. One-third of all saxophones in the world are made in Taiwan, most of them in the city of Houli. (@Linc_tw)
25. 48% of solo male drivers wear a seatbelt. When there is a man in the passenger seat, the rate drops to 34%. When there’s a woman sitting next to him, the rate jumps to 59%. (“The relation between seat belt use of drivers and passengers”)
26. In the NBA, taller players are not better than shorter players. There is no correlation between height and scoring success. (Matthew Hahn)
27. 85% of people breathe out of only one side of their nose at a time, and they switch sides every 12 to 15 minutes. People who don’t switch nostrils are at a higher risk for diabetes, because breathing through your right nostril only increases blood glucose levels and uses more oxygen. (“About 85 percent of people only breathe out of one nostril at a time”)
28. Pledge cards work! Donors give 50% more if they decide now to give later. (“Time inconsistent charitable giving”)
    
29. Women prefer tall men to short men, so most men lie about their height, claiming to be, on average, two inches taller than they actually are. Likewise, women lie about their weight by an average of about fifteen pounds. (When Men Behave Badly)
30. People who display their COVID vaccination status on dating sites are 14% more likely to get a match. (Andy Slavitt)
31. Most people who own trucks don’t need them. In a one-year period, 75% of truck owners tow something once or less, and a third do not haul anything in their truck beds at all. On average, truck ownership functions as a form of costly signaling. (“Tesla’s new pickup will struggle to win over the Midwest’s truck die-hards”)
32. Humans are evolving! We are growing a third blood vessel in our arms—the persistent median artery. In the 1880s, only 10% of the population had it, but by the late twentieth century 30% did. A majority will by 2100. Natural selection seems to prefer it: the cost of higher risk for carpal tunnel syndrome and other nerve damage is worth the benefit of stronger forearms and a more reliable blood supply. (“More And More Humans Are Growing an Extra Artery”)
    
    
    
33. One in three guitars in the United States is played in church worship bands. Roughly 1 million people play a guitar in church every week. Worship leaders generate roughly $600 million in revenue per year for the guitar industry. (“Is Praise and Worship Music Driving Guitar Sales?”)
34. After Mohamed Salah, an openly Muslim soccer player, joined Liverpool FC, hate crimes in Liverpool dropped by 16%. (“Can Exposure to Celebrities Reduce Prejudice?”)
35. Want affordable housing in your city? Allow developers to build and sell more high-end units at market rates. 100 new luxury apartments creates 60 vacancies in the bottom half of the market and 29 vacancies in the bottom quintile. (“How luxury apartment buildings help low-income renters”)
36. Want more expensive housing in your city? Increase the minimum lot size requirements. When a city doubles the minimum lot size in residential zones, real estate prices go up 14% and rent goes up 6%. (“The Effects of Residential Zoning in U.S. Housing Markets”)
37. Your Converse shoes are actually slippers. In 2003, Converse added a thin layer of fabric to the soles, which, according to the 2002 U.S. Customs Bulletin, technically classifies them as slippers instead of shoes, which must have rubber soles. Thus, Converse pays a 2% import tax, instead of the normal 25% import tax on shoes. (“Your Sneaker Is a Slipper” and “Evolution of the Outer Sole”)
38. The F-117 stealth bomber’s strange shape doesn’t help it escape radar detection. Instead, its design reflects the limitations of 1970s-era computer processing power. (Wikipedia)
    
    
    
39. Infant mortality rises 0.31 deaths per thousand births in the 12-month period following a mass emergence of cicadas, which happens on 13- and 17-year cycles. In these years, farmers apply 13-22% more pesticides, and the rise in mortality is among the unintended environmental consequences. (“Cicadian Rhythm: Insecticides, Infant Health and Long-term Outcomes”)
40. 57% of people who own a second home think their income is below average. (“Misperceiving inequality”)
41. The science of standing in line is fascinating: if an average of 5.8 customers per hour arrive at a bank and need 10 minutes of help, then the average wait time is 3 minutes if there are two tellers working. But if only a single teller is working, then the wait time jumps from 3 minutes to to 5 hours! (“What happens when you add a new teller?”)
42. 7% of Montreal’s population, or about 115,000 of its 1.6 million people, moves on a single day every year, July 1. The practice dates back to an 18th-century French colonial law protecting farmers from eviction before winter snows had melted, which meant all leases ended on a single day. (Wikipedia, via David Perell)
43. Plastic-wrapped cucumbers at the grocery store are 4.9 times better for the environment than non-wrapped cucumbers. The plastic reduces prevents spoilage by extending the shelf life 60%, which means fewer cucumbers need to be grown, shipped, and sold. Each non-wrapped spoiled cucumber has an environmental impact equal to 93 plastic-wrapped cucumbers. (“Plastic food packaging gets a bad rap, but does it always deserve it?”)
44. Dog owners are more likely to vote conservative, and cat owners are more likely to vote liberal. (“Pets and Politics”)
45. Papercuts hurt so much because, at the microscopic level, the edge of paper is basically a sawblade. (@Rainmaker1973)
    
    
    
46. Superfluous apologies work! If you preface a request with “I’m sorry about the rain,” people are much more likely to comply. In one case, 47% of people handed their cell phone to a stranger after the stranger apologized for something that had nothing to do with the request. But without the fake apology, only 9% did. (“I’m sorry about the rain! Superfluous apologies demonstrate empathic concern and increase trust”)
47. It is illegal to swear in Michigan. According to a 1931 law still on the books, if you “profanely curse or damn or swear by the name of God, Jesus Christ or the Holy Ghost,” then you are guilty of a misdemeanor. (Michigan Penal Code)
48. In the 1920s, the amount of material used in women’s dresses dropped from nineteen yards of fabric to just seven. (Domestic Revolutions: A Social History of American Family Life)
49. It’s more dangerous to drive a car without a helmet than ride a bike without a helmet. The chance of a driver getting a head injury is 0.46 for every million miles driven, but the chance for a cyclist is less: 0.41 per million miles. (“Why it makes sense to bike without a helmet”)
50. In 1831, the Swedish navy almost ran out of timber to repair its ships, so the government planted oak forests to ensure a steady supply. When the trees reached maturity in 1975, the navy informed the government the wood was no longer needed. (“Ekskogen på Visingsö”)
51. A one-in-a-million chance of death is called a micromort. 1 micromort is equivalent to smoking 1.4 cigarettes, eating 100 steaks, walking 17 miles, or going on a bombing mission over Germany in World War II for 1 second. Hang gliding is 8 micromorts; giving birth is 120 micromorts, and running a marathon is 7 micromorts. (Getting COVID is about 10,000 micromorts, which makes COVID about as risky as flying a bombing mission over Germany for 2.77 hours. The COVID vaccine is 0.2 micromorts.) (Wikipedia)
52. Why you swing your arms when you walk: it’s more efficient! Keeping your arms in sync with your legs⁠—extending your left arm when you take a step with your left foot⁠—takes 26% more energy. (“Why Do We Swing Our Arms When We Walk?”)

Miscellaneous

I spent quite a bit of the year reading about Dutch history from roughly 1349 to 1582. If you’re into that kind of thing, then Jonathan Israel’s The Dutch Republic and Jan de Vries & Ad van der Woude’s The First Modern Economy are both excellent, though not exactly beach reads. Geoffrey Parker’s The Dutch Revolt is also good. I didn’t read much fiction this year, but I really enjoyed Andy Weir’s The Martian and James Baldwin’s Another Country. I read Katherine Paterson’s Bridge to Terabithia and Lynda Mullaly Hunt’s Fish in a Tree out loud to my daughter this fall, and we loved both. I didn’t love Annie Duke’s Thinking in Bets while I was reading it, but I still think about the ideas in the book every day, so as time goes on, it will probably become one of the best books of the year. I thought Steven Pinker’s Rationality was good, but I didn’t have the same mind-bending experience I had when I read his Better Angels of Our Nature a few years ago. On the American revolution, I read Gordon Wood’s The Radicalism of the American Revolution, Bernard Bailyn’s The Ideological Origins of the American Revolution, and Forrest McDonald’s Novus Ordo Seclorum. All three are outstanding. Harold J. Berman’s Law and Revolution completely changed how I think about the history of the West, and I’m still following the footnotes months later. The best book I read this year was Kristin du Mez’s Jesus and John Wayne. The complete list of books I read in 2021 is listed here.

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