See How Yearbook Photos Have Evolved Over the Past Century

Cornell University Library
Cornell University Library

High school picture day is a tradition that dates back to the beginning of the 20th century. And while the basic formula of a front-facing pose against a neutral background hasn’t changed much in the past 100 years or so, facial expressions certainly have. For a better look at the similarities and differences between yearbook photos through the decades, researchers from the University of California, Berkeley recently compiled data on tens of thousands of images from the past 110 years [PDF].

The team's research marks one the first times machine-learning algorithms have been used to mine historic data from a collection of photographs. The high school yearbook photos were gathered from the digital databases of local libraries across the U.S. After downloading 150,000 pictures, the team eliminated all the photographs that weren’t front-facing portraits, leaving them with 37,000 samples from over 800 yearbooks from 26 states.

Next, they generated an “average” image for the men and women of each decade. By superimposing the groups of portraits together, they were able to then identify any trends exhibited in the composite images. One of the more interesting changes these pictures showed was the evolution of the subjects’ smiles.

When photography was still gaining popularity at the turn of the 20th century, it was normal for people to adopt a neutral expression for their portraits. According to the authors of the study, the earlier expressions might were partly a product of the beauty standards of the time: "Etiquette and beauty standards dictated that the mouth be kept small—resulting in an instruction to 'say prunes' (rather than cheese) when a photograph was being taken." (Not, it should be noted, due to long exposure times. By the late 19th century, innovations in photography had cut exposure time down to mere seconds.) 

As the 20th century wore on, the classic posed smile we adopt today began to emerge. An algorithm measuring the yearbook photos' shifting degrees of lip curvature supports this, and the trend can also be clearly observed in the composite images. Notably, this was around the same time that Kodak began releasing advertisements of happy people "smiling for the camera." The authors of the paper suggest this had a significant impact on how people chose to pose for their pictures.

The process also revealed data-backed proof of shifting trends in other areas, such as average hairstyles for each decade. While women of the '30s rocked finger waves, pin curls dominated the '40s and '50s, Afros took over in the '70s, and perms and bangs had their moment in the '80s and '90s. The data the team gathered on the progress of male fashion was slightly less interesting: men have been wearing standard suits in their high school yearbook pictures for over a century. 

Images Courtesy of the Cornell University Library.

[h/t: MIT Technology Review]

10 Rad Gifts for Hikers

Greg Rosenke/Unsplash
Greg Rosenke/Unsplash

The popularity of bird-watching, camping, and hiking has skyrocketed this year. Whether your gift recipients are weekend warriors or seasoned dirtbags, they'll appreciate these tools and gear for getting most out of their hiking experience.

1. Stanley Nesting Two-Cup Cookset; $14

Amazon

Stanley’s compact and lightweight cookset includes a 20-ounce stainless steel pot with a locking handle, a vented lid, and two insulated 10-ounce tumblers. It’s the perfect size for brewing hot coffee, rehydrating soup, or boiling water while out on the trail with a buddy. And as some hardcore backpackers note in their Amazon reviews, your favorite hiker can take the tumblers out and stuff the pot with a camp stove, matches, and other necessities to make good use of space in their pack.

Buy it: Amazon

2. Osprey Sirrus and Stratos 24-Liter Hiking Packs; $140

Amazon

Osprey’s packs are designed with trail-tested details to maximize comfort and ease of use. The Sirrus pack (pictured) is sized for women, while the Stratos fits men’s proportions. Both include an internal sleeve for a hydration reservoir, exterior mesh and hipbelt pockets, an attachment for carrying trekking poles, and a built-in rain cover.

Buy them: Amazon, Amazon

3. Yeti Rambler 18-Ounce Bottle; $48

Amazon

Nothing beats ice-cold water after a summer hike or a sip of hot tea during a winter walk. The Yeti Rambler can serve up both: Beverages can stay hot or cold for hours thanks to its insulated construction, and its steel body (in a variety of colors) is basically indestructible. It will add weight to your hiker's pack, though—for a lighter-weight, non-insulated option, the tried-and-true Camelbak Chute water bottle is incredibly sturdy and leakproof.

Buy it: Amazon

4. Mappinners Greatest 100 Hikes of the National Parks Scratch-Off Poster; $30

Amazon

The perfect gift for park baggers in your life (or yourself), this 16-inch-by-20-inch poster features epic hikes like Angel’s Landing in Zion National Park and Half Dome in Yosemite National Park. Once the hike is complete, you can scratch off the gold foil to reveal an illustration of the park.

Buy it: Amazon

5. National Geographic Adventure Edition Road Atlas; $19

Amazon

Hikers can use this brand-new, updated road atlas to plan their next adventure. In addition to comprehensive maps of all 50 states, Puerto Rico, Canada, and Mexico, they'll get National Geographic’s top 100 outdoor destinations, useful details about the most popular national parks, and points on the maps noting off-the-beaten-path places to explore.  

Buy it: Amazon

6. Adventure Medical Kits Hiker First-Aid Kit; $25

Amazon

This handy 67-piece kit is stuffed with all the things you hope your hiker will never need in the wilderness. Not only does it contain supplies for pain, cuts and scrapes, burns, and blisters (every hiker’s nemesis!), the items are organized clearly in the bag to make it easy to find tweezers or an alcohol wipe in an emergency.

Buy it: Amazon

7. Hiker Hunger Ultralight Trekking Poles; $70

Amazon

Trekking poles will help increase your hiker's balance and stability and reduce strain on their lower body by distributing it to their arms and shoulders. This pair is made of carbon fiber, a super-strong and lightweight material. From the sweat-absorbing cork handles to the selection of pole tips for different terrain, these poles answer every need on the trail. 

Buy it: Amazon

8. Leatherman Signal Camping Multitool; $120

Amazon

What can’t this multitool do? This gadget contains 19 hiking-friendly tools in a 4.5-inch package, including pliers, screwdrivers, bottle opener, saw, knife, hammer, wire cutter, and even an emergency whistle.

Buy it: Amazon

9. RAVPower Power Bank; $24

Amazon

Don’t let your hiker get caught off the grid with a dead phone. They can charge RAVPower’s compact power bank before they head out on the trail, and then use it to quickly juice up a phone or tablet when the batteries get low. Its 3-inch-by-5-inch profile won’t take up much room in a pack or purse.

Buy it: Amazon

10. Pack of Four Indestructible Field Books; $14

Amazon

Neither rain, nor snow, nor hail will be a match for these waterproof, tearproof 3.5-inch-by-5.5-inch notebooks. Your hiker can stick one in their pocket along with a regular pen or pencil to record details of their hike or brainstorm their next viral Tweet.

Buy it: Amazon

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100 of the Most Commonly Misspelled Words in the English Language

She's having a dilemma about how to spell dilemma.
She's having a dilemma about how to spell dilemma.
franckreporter/iStock via Getty Images

Since many apps and programs now come with built-in spellcheckers to catch pesky errors—and even correct them automatically—you’re less likely to be embarrassed if you always forget how to spell embarrass.

You’re also not alone. Lexico used data from the Oxford English Corpus, which monitors the usage of more than 2 billion English words, to compile a list of 100 most commonly misspelled words. Embarrass is one of them; people have trouble remembering that it has two r’s, writing it as embarass instead.

Of all the words on the list, more than two dozen have common misspellings related to double letters. For some of those entries, people seem to know there’s a double letter somewhere in the word, but they often choose the wrong letter to repeat—Caribbean, for example, is often spelled Carribean, and bizarre becomes bizzare. Others have multiple double letters, and people accidentally omit one, like missing the second t in committee or the second n in millennium.

Double letters aren’t the only recurring issue on this list. The old “i before e except after c” mnemonic rhyme hasn’t stuck for everyone; the two vowels are often mistakenly swapped in achieve, believe, friend, piece, receive, and siege. As a testament to how frustrating the English language can be, the words weird and foreign, two of the (many) exceptions to the “i before e” rule, are often misspelled as wierd and foriegn.

Another common vocalic blunder involves a’s and e’s in suffixes. It’s appearance, not appearence; calendar, not calender; and tendency, not tendancy. There aren’t always obvious mnemonic devices to help you keep these straight, but Reader’s Digest suggests exclaiming “Eeek!” whenever you need to remember that cemetery has three e’s and no a’s.

See all 100 words—with the correct spelling listed first, and the common misspelling listed after it—below. And if you’re not the greatest speller, don’t worry; neither were Jane Austen, F. Scott Fitzgerald, and these 9 other historical figures.

  1. accommodate // accomodate
  1. achieve // acheive
  1. across // accross
  1. aggressive // agressive
  1. apparently // apparantly
  1. appearance // appearence
  1. argument // arguement
  1. assassination // assasination
  1. basically // basicly
  1. beginning // begining
  1. believe // beleive, belive
  1. bizarre // bizzare
  1. business // buisness
  1. calendar // calender
  1. Caribbean // Carribean
  1. cemetery // cemetary
  1. chauffeur // chauffer
  1. colleague // collegue
  1. coming // comming
  1. committee // commitee
  1. completely // completly
  1. conscious // concious
  1. curiosity // curiousity
  1. definitely // definately
  1. dilemma // dilemna
  1. disappear // dissapear
  1. disappoint // dissapoint
  1. ecstasy // ecstacy
  1. embarrass // embarass
  1. environment // enviroment
  1. existence // existance
  1. Fahrenheit // Farenheit
  1. familiar // familar
  1. finally // finaly
  1. fluorescent // florescent
  1. foreign // foriegn
  1. foreseeable // forseeable
  1. forty // fourty
  1. forward // foward
  1. friend // freind
  1. further // futher
  1. gist // jist
  1. glamorous // glamourous
  1. government // goverment
  1. guard // gaurd
  1. happened // happend
  1. harass // harrass
  1. honorary // honourary
  1. humorous // humourous
  1. idiosyncrasy // idiosyncracy
  1. immediately // immediatly
  1. incidentally // incidently
  1. independent // independant
  1. interrupt // interupt
  1. irresistible // irresistable
  1. knowledge // knowlege
  1. liaise // liase
  1. lollipop // lollypop
  1. millennium // millenium
  1. Neanderthal // Neandertal
  1. necessary // neccessary
  1. noticeable // noticable
  1. occasion // ocassion
  1. occurred // occured
  1. occurrence // occurance, occurence
  1. pavilion // pavillion
  1. persistent // persistant
  1. pharaoh // pharoah
  1. piece // peice
  1. politician // politican
  1. Portuguese // Portugese
  1. possession // posession
  1. preferred // prefered
  1. propaganda // propoganda
  1. publicly // publically
  1. really // realy
  1. receive // recieve
  1. referred // refered
  1. religious // religous
  1. remember // rember, remeber
  1. resistance // resistence
  1. sense // sence
  1. separate // seperate
  1. siege // seige
  1. successful // succesful
  1. supersede // supercede
  1. surprise // suprise
  1. tattoo // tatoo
  1. tendency // tendancy
  1. therefore // therefor
  1. threshold // threshhold
  1. tomorrow // tommorow, tommorrow
  1. tongue // tounge
  1. truly // truely
  1. unforeseen // unforseen
  1. unfortunately // unfortunatly
  1. until // untill
  1. weird // wierd
  1. wherever // whereever
  1. which // wich

[h/t Lexico]